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HOWARD, JOANNE KAY HERGENROTHER. "COGNITIVE ADAPTATION AND THE SCHOOLAGER WITH ASTHMA." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183895.
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The purpose of this study was to examine the interrelationships among the themes of Taylor's (1983) Cognitive Adaptation Theory for schoolagers with asthma. In addition, the influence of Taylor's (1983) themes on the children's social behavior was also tested. The three themes of Taylor's (1983) theory included A Search for Meaning, Restoration of Self-Esteem, and Gaining a Sense of Self-Mastery. Two components of A Search for Meaning included the Impact of Disease and the Cause of Disease. Relating Behaviors-Cooperating Behaviors was the index of social behavior. Forty-five Caucasian children between the ages of seven and ten years who had a diagnosis of asthma and did not have any mental disability were the convenient sample. Data were collected in the children's homes. Three questionnaires and two interviews were used to measure Taylor's (1983) themes and Relating Behaviors-Cooperating Behaviors. Descriptive statistics were used to answer the research questions and provide additional findings related to the conceptual framework. Two relationships among Taylor's (1983) themes were significant (p ≤ .05). Children who reported greater impact of asthma upon their lives (Impact of Disease) reported lower self-esteem (Restoration of Self-Esteem). Children who reported greater impact of asthma upon their lives (Impact of Disease) also reported a lesser internal locus of control orientation (Gaining a Sense of Self-Mastery). The Cause of Disease was the only concept which correlated significantly with Relating Behaviors-Cooperating Behaviors and thus, influenced this concept. Children who named a cause for their asthma reported more relating and cooperating skills. The Cause of Disease explained 6.5% of the variance for Relating Behaviors-Cooperating Behaviors. Characteristics of the children's asthma condition and their families were significantly related to the themes of Taylor's (1983) theory and Relating Behaviors-Cooperating Behaviors. Developmental differences were found from age group analyses. The classification of the children's responses for the cause of asthma and reliability and validity estimation for the HIIS were also reported. Five potential sources of error which may have affected the findings included design, instrument, subject, investigator, and specification errors. Suggestions for future research with the conceptual framework were discussed.
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Volos, Haris I. "Cognitive Radio Engine Design for Link Adaptation." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/29148.
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In this work, we make contributions in three main areas of Cognitive Engine (CE) design for link adaptation. The three areas are CE design, CE training, and the impact of imperfect observations in the operation of the CE.
First, we present a CE design for link adaptation and apply it to a system which can adapt its use of multiple antennas in addition to modulation and coding. Our design moves forward the state of the art in several ways while having a simple structure. Specifically, the CE only needs to observe the number of successes and failures associated with each set of channel conditions and communication method. From these two numbers, the CE can derive all of its functionality: estimate confidence intervals, balance exploration vs. exploitation, and utilize prior knowledge such as communication fundamentals. Finally, the CE learns the radio abilities independently of the operation objectives. Thus, if an objective changes, information regarding the radio's abilities is not lost.
Second, we provide an overview of CE training, and we analytically estimate the number of trials needed to conclusively find the best performing method in a list of methods sorted by their potential performance. Furthermore, we propose the Robust Training Algorithm (RoTA) for applications where stable performance is of topmost importance. Finally, we test four key training techniques and identify and explain the three main factors that affect performance during training.
Third, we assess the impact of the estimation noise on the performance of a CE. Furthermore, we derive the effect of estimation delay, in terms of the correlation between the observed SNR and the true SNR. We evaluate the effect of estimation noise and delay to the operation of the CE individually and jointly. It is found that impairments on learning make the CE more conservative in its choices leading to submaximal performance. It is found that the CE should learn using the impaired observations, if the observations are highly correlated with the actual conditions. Otherwise, it is better for the CE to learn with knowledge of the ideal conditions, if that knowledge is available.Ph. D.
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Fragonara, Aurora. "La pratique de l’adaptation : approches sémiolinguistique et cognitive." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0152/document.
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Ce travail interroge le rapport entre la parole et son contexte médiatique d’énonciation. À ces fins, nous avons choisi comme observable l’adaptation en vertu du fait que cette pratique comporte le passage du même contenu d’un média à un autre. Nous avons constitué un corpus contrastif formé du Petit Prince de Saint-Exupéry et de son adaptation théâtrale par Virgil Tanase, choisie parmi d’autres selon des critères de représentativité et pertinence par rapport à notre angle d’attaque linguistique. Afin de traiter ce corpus dans une perspective linguistique, nous avons convoqué des notions et des cadres théoriques issus de la théorie de l’énonciation, la pragmatique et la linguistique cognitive. Des notions sémio-narratologiques ont également été mises à contribution. L’analyse, divisée en trois parties, se focalise d’abord sur les propriétés sémiotiques (schéma actantiel et macroséquence) et linguistiques (point de vue et isotopie) communes au conte et à la mise en scène. Ces caractéristiques assurent l’équivalence entre adapté et adaptation. Ensuite, sont brièvement analysées les propriétés linguistiques qui permettent le passage du média livre au média théâtre (relation hyponymie/hyperonymie des noms communs et dialogues). Enfin, nous nous focalisons sur les marqueurs qui enregistrent le passage d’un média à un autre en termes de traitement cognitif du référent (déictiques, actes de nomination) de la part de l’instance de réception. Les résultats de cette analyse mettent en lumière l’influence du contexte médiatique sur l’acte d’énonciation selon un double cadre théorique : celui d’une perspective élargie de l’énonciation qui prend en compte l’inscription volontaire et autonome de l’allocutaire dans une situation d’énonciation et celui d’une approche symétrique et réaliste dans le traitement de la référenceOur work enquires about the relation between enunciation and media. We chose the adaptation as a case study, since it is a semiotic practice that requires transferring the same content from one media to another. Hence, we built a contrastive corpus based on Le Petit Prince by Antoine de Saint-Exupéry and its theatrical adaptation by Virgil Tanase, which we consider to be the most representative for our linguistic approach. In order to adopt a linguistic perspective, we articulate notions and frameworks from the French theory of enunciation, pragmatics and cognitive linguistics. Notions from a narratology background are also contributive. The corpus analysis is organized in three main sections. The first one states the equivalence between the adapted story and its adaptation through some semiotic (actantial model and model of narrative sequence) and linguistic parameters (point of view and isotopy) shared by the book and the play. The second part briefly points out the features that enable the story to transfer from one media to another (dialogues, lexical choices). The third and final part focuses on verbal marks (deictic expressions, naming) that encode the media change (from the book to the play) and require the audience to perform some cognitive processing to properly understand the theatrical play. Results of this analysis show the influence of media context on enunciation while relating this kind of context to two linguistic frameworks : an extended enunciation theory, in which the addressee is actively taking part in the meaning production, and a reference theory based on a symmetric relationship between word and object in meaning production
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Tournier, Isabelle. "Adaptation Cognitive et Vieillissement : entre Automatisme et Flexibilité." Thesis, Bordeaux 2, 2010. http://www.theses.fr/2010BOR21785/document.
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L’objectif général de cette thèse est d’étudier l’évolution au cours du vieillissement des processus automatiques et contrôlés, nécessaires à une bonne adaptation cognitive quotidienne. Nous nous intéressons à l’influence de différentes variables cognitives (mémoire de travail, vitesse de traitement et vocabulaire) ainsi qu’aux préférences de routinisation sur l’expression de ce possible effet de l’âge. Des épreuves de fluidités sémantiques simples (Expérience 1) et alternées (Expérience 2 et 3) et des formats simples (Expérience 5a et 6a) et alternés (Expérience 5b et 6b) de la tâche de Hayling ont été réalisés par des adultes jeunes (18-30 ans), âgés (60-74 ans) et très âgés (75 ans et plus). Ces épreuves nous permettent d’étudier le processus automatique à travers la diffusion de l’activation en mémoire sémantique et les processus contrôlés par le biais de l’inhibition et de la flexibilité. L’activité cérébrale associée à l’exécution de fluidités simples et alternées est étudiée chez des participants âgés à l’aide de l’imagerie optique (Expérience 4). Les résultats obtenus sont en faveur d’une réduction avec l’âge de l’efficience des processus contrôlés alors que celle des processus automatiques semble conservée. Des phénomènes de compensation se mettraient en place au cours du vieillissement, s’appuyant sur les processus automatiques et les connaissances accumuléesThe aim of this thesis is to investigate the changes in automatic and controlled processes during aging which are necessary for satisfactory daily cognitive adaptation. The focus is the impact of various cognitive variables (i.e., working memory, speed of processing and vocabulary) and preferences for routines on the expression of this possible age effect. Simple (Experiment 1) and alternating fluency tasks (Experiments 2 and 3) as well as a simple (Experiments 5a and 6a) and alternating version of the Hayling task (Experiments 5b and 6b) were administered to young adults (18-30 years old), older adults (60-74 years old) and older-old adults (75 years old and over). These tasks allowed the study of automatic processes through spreading activation in semantic memory and of controlled processes through inhibition and flexibility. The cerebral activity associated with simple and alternating fluency task execution was investigated in elderly adults with near-infrared spectroscopy (Experiment 4). The results suggest a decrease with age in the efficiency of controlled processes whereas the efficiency of automatic processes seems to be preserved. Thus, compensation based on automatic processes and accumulated knowledge may appear during aging
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Houde, John Francis. "Sensorimotor adaptation in speech production." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10273.
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Stein, Mark John. "Cognitive Adaptation to Severe Angina or Small Heart Attack." Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490321.
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Naeem, Farooq. "Adaptation of cognitive behaviour therapy for depression in Pakistan." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/364922/.
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Background: Cognitive Behaviour Therapy (CBT) in its current form might not be applicable in Non Western cultures. Differences between western and non western cultures have been reportedly widely. Psychotherapy was developed in the west and is underpinned by many beliefs and practices which might be specific only to the Western culture. However, in order to modify CBT we need to understand whether the concepts associated with the CBT might cause conflicts among people who receive therapy, the barriers in giving therapy and the views of the patients. This project was carried out mainly in Pakistan to adapt CBT for depression. Aims: To find out if CBT can be successfully adapted in a Non Western culture. Methods: This was a mixed methods Study. The project consisted of two phases. In the first phase a series of studies were carried out, including interviews with psychologists, patients and group discussions with university students about their views regarding concepts underlying therapy. In the second phase a CBT for depression manual was modified using guidelines which were developed on the basis of studies carried out in the first phase. This manual was then tested in a small pilot project using a Randomised Controlled Trial (RCT) design. Results: We were able to find themes and subthemes, on the basis of studies in first phase of the project, which were used to modify a CBT for depression manual. We developed an adaptation framework on the basis of the identified factors. This framework consisted of three broad themes (name theme) with each subdivided into seven sub themes. The pilot study showed that therapists trained for a short period and under supervision can deliver CBT using a manual. Results of pilot showed that modified CBT is more effective than 'care as usual' in reducing symptoms of depression. Conclusions: The study demonstrates that for CBT to be effective in Non Western cultures, it needs modification. This can be achieved using small scale qualitative studies locally, which explore experience of therapists working in a given culture as well as by exploring the views of patients. Further information can be obtained by talking to the members of that community about concepts underlying CBT. However, these are preliminary findings and further research needs to be done to explore this area further.
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Guay, Karianne. "Adaptation cognitive chez les adolescents ayant subi la maltraitance." Doctoral thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69030.
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Les répercussions développementales de la maltraitance sont largement documentées dans les écrits scientifiques. Sur le plan cognitif, on constate que certains enfants se montrent hypervigilants par rapport aux signaux associés à un danger potentiel, ce qui peut se traduire par une allocation privilégiée de l'attention envers ces stimuli. Un tel biais attentionnel permet de détecter rapidement une menace afin de s'adapter à un milieu de vie adverse. Il peut en contrepartie accaparer inutilement l'attention en contexte sécuritaire. Or, l'état des connaissances demeure limité en ce qui concerne plus spécifiquement la manifestation de ce phénomène au cours de la période juvénile. La présente thèse cherche donc à vérifier si un biais attentionnel envers les stimuli menaçants subsiste auprès d'adolescents ayant vécu la maltraitance. À cet effet, 79 adolescents âgés de 12 à 17 ans sont recrutés dans la région de Québec pour former un groupe de 39 jeunes victimes de maltraitance et un groupe comparatif de 40 participants contrôles. Ils effectuent une tâche de clignement attentionnel (CA) qui mesure l'identification correcte des caractéristiques de visages cibles (C1 et C2) introduits dans des séquences rapides de visages neutres. En concordance avec l'hypothèse que des stimuli menaçants pertinents à la tâche devraient entraîner un effet facilitateur sur la performance, un premier chapitre empirique montre qu'une C2 fâchée présentée en situation de ressources limitées semble automatiquement rediriger l'attention vers ce stimulus. Cet effet de capture attentionnelle prend alors la forme d'une compétence cognitive chez les deux groupes d'adolescents étudiés. À l'inverse, une expression menaçante non pertinente à traiter - comme lorsque l'identification du genre d'une C1 fâchée est plutôt requise - paraît détourner l'attention des autres caractéristiques du stimulus. Dans ces conditions, une capture des ressources attentionnelles disponibles se traduit en une difficulté cognitive qui nuit au traitement de l'information cible pour l'ensemble des participants. Les résultats indifférenciés entre les groupes soulignent essentiellement l'absence de biais attentionnel propre aux participants exposés à la maltraitance. Un deuxième chapitre empirique propose donc une approche quantitative permettant de tester autrement l'existence du biais attentionnel tout en approfondissant la compréhension des données issues de la tâche de CA. Des paramètres empruntés à la théorie de détection du signal révèlent que les adolescents du groupe maltraitance ont plus souvent tendance à rapporter avoir vu une C2 lorsqu'elle est absente en comparaison avec le groupe contrôle. Une telle propension s'accompagne d'une stratégie décisionnelle à caractère plus libéral que les participants non exposés à la maltraitance, laquelle s'avère effectivement reconnue pour augmenter la susceptibilité aux erreurs de type fausses alarmes ou le nombre de détections fortuites. Les écarts presque significatifs obtenus entre les groupes demeurent néanmoins indépendants de la valence négative des C1 iii préalablement traitées, confirmant ainsi l'absence de biais attentionnel parmi les adolescents ayant subi la maltraitance. En revanche, des corrélations exploratoires avec les échelles de symptômes psychiatriques du Child Behavior Checklist ouvrent sur certains éléments cliniques à considérer en lien avec les résultats obtenus, dont le niveau d'impulsivité/inhibition des participants. Les conclusions de la thèse impliquent une possible résorption du biais attentionnel envers les visages fâchés observé auprès d'enfants victimes de maltraitance. Les retombées de cette découverte sont intégrées aux connaissances relatives à la maturation des mécanismes de régulation cognitive et comportementale lors de la puberté. Une approche évaluative basée sur les processus est encouragée dans la perspective d'élargir les applications cliniques issues de la recherche expérimentale.The developmental impacts of childhood maltreatment are widely documented in scientific literature. On the cognitive level, some children are found to be hypervigilant in regards to signals associated with a potential danger, which can lead to a privileged allocation of attention toward those stimuli. Such an attentional bias allows a quick threat detection in order to adapt oneself in an adverse environment. It can, in turn, unnecessarily capture attention in a security context. However, the actual state of knowledge remains limited regarding the manifestation of this phenomenon during the juvenile period more specifically. Therefore, the aim of the present thesis is to verify whether an attentional bias towards threatening stimuli persists among adolescents who have experienced maltreatment. 79 adolescents (48 girls) aged 12 to 17 are recruited in the Quebec City region to form a group of 39 youths who have a history of maltreatment and a comparative group of 40 teenage controls. They perform an attentional blink (AB) task which measure the correct identification of characteristics from target faces (T1 and T2) introduced into a rapid serial presentation of neutral faces. In line with the hypothesis that task-relevant threatening stimuli should have a facilitating effect on performance, a first empirical chapter shows that an angry T2, presented in a resource-constrained situation, appears to automatically redirect attention to the stimulus. This attentional capture effect then takes the form of a cognitive competence in the two groups of adolescents. On the other hand, a threatening expression that is not relevant to process - as when identifying the gender of an angry T1 is rather required - seems to divert attention from the other characteristics of this stimulus. Under these circumstances, attentional capture results in a cognitive difficulty that impedes the processing of the targeted information for all participants. The undifferentiated results between groups mainly point out the absence of attentional bias specific to participants exposed to maltreatment. A second empirical chapter thus proposes a quantitative approach allowing to test the existence of an attentional bias differently while deepening comprehension of the AB task data. Parameters based on the Signal Detection Theory reveal that adolescents of the maltreatment group are more likely to report having seen a T2 when it was in fact absent in comparison with the control group. Such a tendency is accompanied by a decision-making strategy of a more liberal nature than participants not exposed to maltreatment, which is effectively known to increase susceptibility to false alarm errors or the number of incidental detections. Nevertheless, these almost significant differences between groups remain independent of the negative valence of previously treated T1, thus confirming the absence of attentional bias among the adolescents who experienced maltreatment. This being, exploratory correlations with the psychiatric symptoms scales of the Child Behavior Checklist open up on some clinical elements to v consider with regard to the results, notably participants' level of impulsivity/inhibition. The thesis conclusions imply a possible extinction of the threat-related attentional bias observed among children with a history of maltreatment. Impacts of this discovery are integrated with knowledge about the maturation of cognitive and behavioral regulatory mechanisms during puberty. A processoriented evaluation approach is encouraged with a view of enhancing clinical benefits from experimental research.
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Rendon, Regina A. "Prism adaptation in a case of cerebellar agenesis." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50517.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 1998.Includes bibliographical references (p. 19-20).
Normal subjects adapt quickly to the displacing effects of prism goggles. A measure of this adaptation comes from the negative aftereffects in reaching that subjects show after the prism goggles are removed. Neural circuitry within the cerebellar cortex has been implicated as the site of plasticity for visuomotor adaptation. An opportunity to test a 15-year-old boy, A.C., with near complete cerebellar agenesis allowed us to determine whether cerebellar structures are critical for prism adaptation to occur. A.C. was tested on two separate occasions, twice using his left hand, and once using his right hand. He wore prism goggles while pointing to a vertical line at each of nine target locations in baseline, exposure, and postexposure conditions. The position of his finger was recorded after each response. In the exposure condition, the goggles were adjusted to 11" displacement to the right when A.C. pointed with his left hand, and to the left when he pointed with his right hand. He received visual feedback only in the exposure condition. His results were compared to those of 20 normal control subjects (NCS). Independent measures of performance and adaptation were calculated for left- and right-handed pointing by each subject. A.C. showed greater variablity in pointing with his right (nonpreferred) hand compared to his left hand and compared to NCS. An ordinal ranking indicated that his adaptation scores did not differ significantly from those of the NCS for either the left (p = 0.30 ) or right hand (p = 0.22). While these results do not disprove the theory that the cerebellum plays a role in normal adaptation, it does indicate that neural structures outside the cerebellum are sufficient to allow adaptation to occur.
by Regina A. Rendon.
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Lundqvist, Anna. "Cognitive functions in drivers with brain injury : anticipation and adaptation /." Linköping : Univ, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5159.
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Morineau, Thierry. "Adaptation cognitive a un environnement virtuel, lors de premieres immersions." Angers, 1996. http://www.theses.fr/1996ANGE0027.
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Cette recherche vise a mettre en evidence le mode d'adaptation cognitive que l'individu va choisir, lors d'une premiere immersion dans un environnement virtuel. Pour poser une hypothese, une analyse de la structure d'un environnement virtuel a ete realisee. Elle indique qu'un contexte de ce type constitue un monde de symboles. Aussi, a la lumiere de theories qui envisagent une interaction entre les mecanismes de l'adaptation immediate et ceux acquis durant l'ontogenese, nous faisons l'hypothese que les sujets pour la premiere fois immerges, activeront des schemes symboliques archaiques comme reponses adaptatives au virtuel. Au niveau experimental, l'influence de l'environnement virtuel sur la cognition et la mise en oeuvre de schemes symboliques apparaissent dans les resultats. De plus, la mise a l'epreuve de la rationalite des sujets indique qu'une part importante, de sujets adultes raisonnent de maniere preoperatoire, dans le virtuelThis research attempts to show the mode of cognitive adaptation used by human being, during a first immersion in virtual environment. To propose a hypothesis, an analysis of the virtual environment structure has been realised. It suggests that this kind of context consists in a world of symbols. So, and in accordance with theories which take the interaction between immediate adaptation mechanisms and those acquired during ontogenesis into account, the hypothesis can be done that subjects immersed for the first time would activate archaic symbolic schemes as adaptative responses to virtuality. At experimental level, virtual environment influence on cognition and symbolic schemes activation have been demonstrated. Moreover, testing of subjects rationality points out that an important part of adults reason out in a preoperational way, in virtual environment
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Albistegui-DuBois, Richard Michael. "Adaptation to inverted vision functional imaging, cognitive testing and observation /." Diss., Restricted to subscribing institutions, 2004. http://proquest.umi.com/pqdweb?did=828432651&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Busch, Hillevi. "When pain remains : Appraisals and adaptation." Doctoral thesis, Stockholm : Dept. of Psychology, Stockholm University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6992.
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Nelson, Jeffrey. "Executive functioning and the adaptation to novelty." University of Western Australia. School of Psychology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0157.
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[Truncated thesis] This thesis is concerned with executive functioning in two different but related ways. The first is as an information processing construct in cognitive psychology. There are many different conceptualisations of the information processing basis of executive functioning but this thesis will pursue the notion that executive functioning is best thought of as adaptation to novelty. In the thesis, this will be operationalised using performance indices (principally reaction time) from a number of information processing tasks. These tasks have typically been used in the literature to index either executive functioning or speed of information processing. Both kinds of tasks are used to tackle the second concern of this thesis, namely, how executive functioning is measured. The data analytic techniques developed in this thesis are based on the hypothesis that executive functioning is the process or processes involved in resolving task novelty and consequently measurement will be enhanced through an analysis of performance changes within tasks as the task changes from novel to familiar. The analysis methods will be based largely on the computation of coefficient of variation of reaction time in successive performance windows across the information processing tasks. An elderly sample was chosen for this thesis because of a history of research that has attempted to determine whether cognitive deficits in the elderly are the consequence of the slowing of information processing speed or to impairment in executive functioning. ... The analysis was driven by the hypothesis that a significant shift in the coefficient of variation would mark a transition from novelty to familiarity in task performance and hence from executive to non-executive phases. Three methods were applied to individual performance curves to determine the point at which for each task this transition occurred. Using criterion measures of variability to separate the task data into two stages, analyses showed, contrary to the hypothesis, that later task performance was more highly associated with executive functioning than in initial task performance. The fourth stage of analysis (Chapter 7) applied confirmatory factor analysis to the newly-formed pre- and post transition data. Evidence was found that the magnitude of the contributions of EF across the pre- and post-criterion phases was stable, failing to support the hypothesis. Finally, structural equation modelling was used to examine how age and intelligence in this elderly sample exerts its influence on task performance and whether EF or IPS was the primary cause of age-related cognitive decline. The results showed that the age and intelligence effects on performance were mediated by the requirement to adapt to novelty. Although there was limited evidence to claim that EF is the primary cause of age-related cognitive decline, ageing effects were only apparent when the participants were adapting to novelty. The thesis concludes that there is some support for the hypothesis that executive functioning is best thought of as the processes underpinning adaptation to novelty. While not a panacea, the analytic techniques developed show promise for future research.
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Korniychuk, Aleksey. "Essays in Behavioral Strategy : Re-biased Search, Misconceived Complexity, and Cognitive Aliens." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLH002/document.
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Ce travail se concentre sur l'idée que la rationalité organisationnelle est limitée: les décideurs recherchent des solutions offrant un minimum de satisfaction et pensent d’une manière qui est typique pour l'homme. La thèse explore cette interaction entre le processus de recherche organisationnelle et la cognition des décideurs et démontre que certains biais (distorsions) dans les aspects caractéristiques de notre pensée peuvent être des instruments de stratégie comportementale.Comme le point de départ, je complète le premier primitif de la rationalité limitée, i.e. la génération et l'évaluation d’alternatives, avec des éléments intégrés de la cognition humaine, tels que la pensée intuitive, spécifiquement l’heuristique d’affect, et des représentations mentales imparfaites. À l'aide de modèles de calcul, j’étudie les effets des biais correspondants à ces éléments de la cognition humaine (préférences affectives et erreurs systématiques dans les représentations mentales) dans le temps lorsque des organisations s'adaptent à des environnements complexes. Cela me permet d'identifier les cycles de vie des éléments de la cognition humaine et de montrer que les organisations devraient gérer (plutôt que d'éliminer) certains biais. Enfin, je fais des propositions et je teste empiriquement un sous-ensemble de mes prédictions.En conclusion, ce travail vise à faire progresser la théorie émergente de la stratégie comportementale en considérant conjointement différents primitifs de la rationalité limitée et en les intégrant aux connaissances existantes en sciences organisationnelles. Une question générale qui motive ce travail est la façon dont les organisations peuvent gérer les nombreuses limites de la rationalité humaineThis work centers on the tenet that organizational rationality is bounded: decision makers search, satisfice, and think in the way that is typical (in its integrity) only of humans. The dissertation explores this interplay between search and decision maker’s cognition and demonstrates how biases in characteristic aspects of our thinking can be instruments of behavioral strategy.As a starting point, I take search, sequential generation and evaluation of alternatives, as the first primitive of bounded rationality and complement it with integral elements of human cognition, such as automatic, intuitive thinking, specifically affect heuristic, and imperfect mental representations of reality. With the help of computational models, I track the effects of the corresponding biases (systematic affective preferences and systematic errors in mental representations) over time as organizations adapt to complex environments. This allows me to identify life cycles of the elements of human cognition and show that organizations should manage (rather than eliminate) some biases over time. Finally, I derive predictions and empirically test a subset of my propositions.In conclusion, this work aims to advance the emerging theory of behavioral strategy by jointly considering different primitives of bounded rationality and integrating them with the existing knowledge in organization sciences. A broad question that motivates this work is how organizations can manage the many bounds to human rationality
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O'Connor, Katherine. "Causal Relations Between Cognitive Control and Language| A Conflict Adaptation Study." Thesis, The George Washington University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1590850.
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Whether neural substrates underlying conflict resolution, or the ability to choose an appropriate response from number of alternate options, are shared across disparate domains is currently unclear. This thesis sought to extend previous studies examining this question by asking whether conflict adaptation occurs between Stroop (a non-syntactic task well-studied in the conflict resolution literature) and two different language tasks. Evidence for bidirectional behavioral interaction between processing of sentences with syntax-semantic conflict and Stroop was found in Experiment 1; however, there were no behavioral interactions between a multiword production task and Stroop in Experiment 2. The difference between these two studies could be consistent with either a domain-general or domain-specific model of conflict processing, as it is unclear whether interactions were not found due to differences in levels of conflict processing or differences in domains of conflict processing. Further research should focus on better distinguishing between these two possibilities. Finally, we also suggest that future research should better characterize the time course of conflict processing.
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Gilligan, Therese M. "Behind the lens : sensorimotor and cognitive after-effects of prism adaptation." Thesis, Bangor University, 2017. https://research.bangor.ac.uk/portal/en/theses/behind-the-lens(fd8b122f-8110-4aa8-ab21-105d476fe0bd).html.
Full textAbstract:
Over a century of research into prism adaptation (PA) has provided many insights into general sensorimotor functions including plasticity and the role of prediction. More recently, the therapeutic value of PA for conditions relating to right hemisphere dysfunction such as hemispatial neglect, and to body schema related conditions such as complex region pain syndrome, have generated a wealth of new knowledge – and more questions (Chapter 1). This thesis examines a cross-section of PA effects: sensorimotor adaptation in healthy participants and cognitive after-effects in a neurological population as well as a group of participants with a virtual lesion. Chapter 2 reports that PA does not induce an after-effect shift in a visual straightahead judgment task, while it does induce after-effects in other tasks which are attributable to a change in state estimates of eye position in the orbit. The results suggest that PA prompts complex changes within ocular proprioception and indicate that the assumption of linear additivity of PA sensorimotor after-effects is a concept requiring re-examination. An increase in priming following both right-shifting and left-shifting PA in patients with a left hemisphere lesion provides a first demonstration of the rehabilitative potential of PA for left hemisphere dysfunctions. Intriguingly, this result also widens the possible candidate mechanisms through which PA facilitates cognitive after-effects (Chapter 3). Finally, this thesis explores the potential influence of the cerebellum in the cognitive after-effects of PA (Chapter 4). It reports, for the first time, that neurodisruption of the right cerebellar hemisphere increases and left cerebellar stimulation decreases word association priming. The results indicate that the two cerebellar hemispheres conjointly schedule the facilitation and inhibition of associative priming. Taken together, the novel findings reported here suggest that previous theoretical stand-points need to be revised and provide a new framework for understanding the relationship between sensorimotor adaptation, cerebellar function and hemispheric interactions in human cognition.
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Grisetto, Fanny. "Impulsivity is not just disinhibition : investigating the effects of impulsivity on the adaptation of cognitive control mechanisms." Thesis, Lille 3, 2020. http://www.theses.fr/2020LIL3H031.
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L’impulsivité est une tendance comportementale fréquemment observée dans la population générale mais à des degrés différents. À ce propos, une forte impulsivité augmente les risques de développer un trouble psychiatrique, tel que les différentes formes d’addiction ou des troubles de la personnalité. Pour comprendre l’émergence de ces divers troubles comportementaux, mon projet de thèse s’est porté sur le rôle du contrôle cognitif dans les manifestations de l’impulsivité. Le contrôle cognitif est, en effet, un ensemble de fonctions cognitives nous permettant d’adapter nos comportements à un environnement changeant, et donc complexe. Durant ma thèse, je me suis plus particulièrement intéressée aux capacités d’adaptation des mécanismes de contrôle proactif et réactif chez des individus impulsifs, principalement dans la population générale mais également auprès de patients alcoolo-dépendants.Les trois premières études de ma thèse ont montré qu’une forte impulsivité était caractérisée par une utilisation moindre des mécanismes proactifs associée à un défaut d’adaptation des mécanismes de contrôle aux demandes externes et aux contraintes internes.Les individus impulsifs exercent moins de contrôle proactif alors que celui-ci devrait être favorisé au vu des caractéristiques contextuelles ou individuelles. Dans une quatrième étude dans laquelle des enregistrements EEG ont été effectués, nous nous sommes intéressées à l’activité cérébrale typique observée au moment de l’exécution des erreurs,nommée ERN/Ne, et dont le rôle serait de signaler les besoins en contrôle. Une réduction de cette activité cérébrale a été observée chez les individus les plus agressifs, mais pas chez les individus les plus impulsifs. Ce résultat suggère que l’émergence de comportements inadaptés pourrait être en partie expliquée par cette réduction du signal d’alarme. Enfin,des résultats préliminaires suggèrent un lien entre un indice périphérique de l’adaptation physiologique (HRV) et les capacités d’adaptation des mécanismes de contrôle. Ce résultat ouvre la voie à de nouvelles interventions thérapeutiques pour la réduction des comportements inadaptés.Dans l’ensemble, les résultats de cette thèse suggèrent que l’impulsivité en population générale est associée à un système de contrôle cognitif moins proactif et moins flexible,menant potentiellement à des comportements inappropriés quand les mécanismes de contrôle en jeu sont inadaptésImpulsivity is a behavioral tendency frequently observed in the general population butat different degrees. Interestingly, higher impulsivity increases the probability to develop and to be diagnosed with a psychiatric disorder, such as substance use or personality disorders. To gain a better understanding on the emergence of such psychiatric disorders, my PhD project focused on the role of cognitive control in impulsive manifestations. Indeed, cognitive control is a set of basic executive functions ensuring adaptive behaviors to an ever-changing and complex environment. More particularly, during my PhD research, I investigated the flexible adaptation between reactive and proactive control mechanisms in impulsive individuals, mainly from the general population but also from an alcohol-dependent population.The first three studies of my thesis revealed that high impulsivity was characterizedby a less-proactive cognitive control system, and associated with a weaker adaptation ofcognitive control mechanisms both to external demands and internal constraints. Morespecifically, I observed that high impulsive individuals less exert proactive control whileit should be favored given contextual or individual characteristics. In the fourth study inwhich EEG signals were recorded, we were interested in the brain activity that is typicallyobserved during errors (i.e., the ERN/Ne), which is thought to signal the need for control.A reduction in this brain activity was observed in high aggressive individuals, but notin high impulsive individuals. This finding suggest that the emergence of maladaptivebehaviors may be explained, to a certain extent, by the reduced alarm signal. Finally, somepreliminary results suggest a link between a peripheral index of physiological adaptation(i.e., HRV) and the capacity to adapt control mechanisms. These findings open newavenues for therapeutic interventions in the reduction in maladaptive behaviors.Overall, findings from the current thesis suggest that impulsivity in the general population is associated with a less proactive and a less flexible cognitive control system, potentially leading to inappropriate behaviors when the control mechanisms at play are maladapted
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Lelonkiewicz, Jarosław Roman. "Cognitive mechanisms and social consequences of imitation." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23490.
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When interacting, people imitate each other. This tendency is truly ubiquitous and occurs in many different situations and behaviours. But what causes it? Several mechanisms have been proposed to contribute to imitation. In this thesis, I focus on three candidate mechanisms: simulation, temporal adaptation, and the goal to affiliate with others. I start by discussing different imitative behaviours, and reviewing the evidence that imitation might at times emerge spontaneously. I also review the evidence suggesting that the three candidate mechanisms might be involved in such emergent imitation. Then, I present three sets of experiments. In the first set, I investigate the role of simulation in language processing. In three experiments, I test the hypothesis that comprehenders use their language production system to simulate their interlocutor, which in turn facilitates their ability to predict the next word they will see or hear. I manipulate whether participants read the sentences silently or aloud and measure their ability to predict the final word of a sentence. My results demonstrate that prediction is enhanced when people use their production system during reading aloud. This gives some credence to the idea that simulation is routinely engaged in language processing, which in turn opens up a possibility that it may contribute to linguistic imitation. In the second set of experiments, I investigate whether temporal adaptation leads agents to imitate features of their partner’s actions. In three experiments, I test this by manipulating the partner’s response speed and the information about the partner’s actions. I show that agents imitate response speed when they are able to observe the partner. Moreover, they adapt to the specific temporal pattern of their partner’s actions. These findings provide evidence for the engagement of the temporal adaptation mechanism during motor interactions, and for its involvement in imitation. In the third set of experiments, I turn to the hypothesis that people engage in linguistic imitation because they want to harness the social benefits it brings. I investigate a key assumption of this hypothesis: that imitation has positive consequences for the social interaction. In three experiments, I manipulate whether participants’ word choice is imitated or counter-imitated by their conversational partner and measure how it affects the participants’ evaluation of the interaction and the partner, and their willingness to cooperate with the partner. I find evidence that linguistic imitation has positive social consequences. These results are consonant with the claim that imitation is motivated by the goal to affiliate and foster social relations. Taken together, these findings suggest that imitation might occur both in motor actions and language, and that it might have diverse causes. My work on language suggests that the tendency to linguistically imitate others could both result from the simulation mechanism, and be motivated by the goal to affiliate. My work on motor actions shows that automatic temporal adaptation contributes to emergent imitation during interactions. This research is conducive to the greater aim of cross-examining the currently known mechanisms of imitation.
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Perrachione, Tyler K. (Tyler Kent). "Impaired learning of phonetic consistency and generalized neural adaptation deficits in dyslexia." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73770.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 81-93).
Developmental dyslexia is a neurological condition that specifically impairs the development of expert reading ability. Phonological processing deficits -- impaired representation of, or access to, the abstract units of spoken language -- have been implicated as the principal source of reading difficulties in dyslexia, independent of other cognitive factors. However, the source of these phonological impairments remains unknown: What mechanisms preclude development of the robust phonological representations critical for reading development? Experiments with phonological processing in dyslexia typically employ metalinguistic tasks that require explicit knowledge about phonological structure, failing to distinguish between access to representations and the representations themselves. Here I report a series of experiments that elucidate the nature of phonological impairments in dyslexia by examining the implicit processing of phonetic variability. Phonetic variability affects language processing at the interface between perceiving the physical speech signal and mapping it onto stored linguistic representations. This approach is well-suited to interrogate the integrity of phonological processing in dyslexia and to provide insight into how phonological representations may come to be impaired in this disorder. In Experiment 1, individuals with dyslexia demonstrated profoundly reduced ability to learn to use phonetic consistency in talker identification, thus reifying the status of phonological representations themselves as fundamentally impaired in this disorder. In Experiment 2, functional magnetic resonance imaging (fMRI) adaptation revealed reduced neural sensitivity to phonetic consistency during speech perception in individuals with dyslexia, indicating impaired rapid, implicit learning of phonetic-phonological consistency. The neural mechanisms that support such learning may be a specific instance of general brain mechanisms for adapting to stimulus consistency. In Experiment 3, fMRI adaptation further revealed that such exiguous neural plasticity in dyslexia is not limited to speech phonetics; instead, the core mechanisms of rapid adaptation to stimulus consistency appear to be dysfunctional in dyslexia, such that neural adaptation was reduced to all stimuli measured, whether auditory or visual, linguistic or non-linguistic. Deficits in neural adaptation may represent disruption of a core rapid plasticity mechanism for perceptual learning, dysfunction of which would impair the ability to develop the robust perceptual (phonological) representations critical to reading development.
by Tyler K. Perrachione.
Ph.D.
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Khan, Z. (Zaheer). "Coordination and adaptation techniques for efficient resource utilization in cognitive radio networks." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514295980.
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Abstract The aim of this thesis is to devise coordination and adaptation techniques that enable the wireless devices operating in a cognitive network to utilize their available resources efficiently. The first part of this thesis considers the case where multiple autonomous devices sense the frequency channels sequentially in some sensing order for spectrum opportunities. In particular, the first part is interested in the scenario where devices with false alarms autonomously select the sensing orders in which they visit channels, without coordination from a centralized entity. An adaptive persistent sensing order selection strategy that allows autonomous adaptations to collision-free sensing orders is proposed and evaluated. It is shown that the proposed strategy converges and maximizes cognitive network throughput compared to a random selection of sensing orders. The second part of this thesis considers the case where distributed devices interact with one another to cooperate to fulfill tasks or to improve the efficiency of network resource usage. Tools from coalition formation game theory are adopted to devise dynamic cooperative strategies for distributed devices. Dynamic coalition formation methods, are proposed for two different network scenarios: 1) Distributed devices operating in an interference channel; 2) Distributed devices performing spectrum sensing. It is observed that in distributed spectrum sensing if the devices pursue their goals selfishly then coalition formation may lead to a suboptimal equilibrium where devices, through their interactions, reach an undesirable coalition structure from a network point of view. The proposed selfish model of dynamic coalition formation is then extended to determine whether and how the coalitional behavior of devices will change if coalition formation is ''not entirely selfish''. It is observed that for the problem of distributed spectrum sensing, average throughput per device is increased when devices cooperate to maximize the overall gains of the group as compared to when they cooperate to increase their individual gains. Finally, in the last part of the thesis, to reduce spectrum sensing overhead and total energy consumption of a cognitive radio network, the problem of sensor selection is considered. Different techniques for selecting devices with the best detection performance are proposed, and it is shown that the proposed device selection methods are able to offer significant gains in terms of system performance as compared to a random selection of devicesTiivistelmä Tämän työn tavoitteena oli kehittää koordinointi- ja adaptointimenetelmiä, jotka mahdollistavat langattomien laitteiden toiminnan kognitiivisessa verkossa ja tarjolla olevien resurssien tehokkaan käytön. Työn ensimmäisessä osassa käsitellään tapausta, jossa useat itsenäiset laitteet havainnoivat taajuuskanavien spektriominaisuuksia sekventiaalisesti jossakin järjestyksessä. Ensimmäisessä osassa ollaan erityisesti kiinnostuneita skenaariosta, jossa virheellisen hälytyksen antava laite automaattisesti valitsee kanavien havainnointijärjestyksen, joka tapahtuu ilman keskusyksikön koordinointia. Tässä työssä ehdotetaan ja evaluoidaan adaptiivinen jatkuva havainnointijärjestyksen valintastrategia, joka sallii itsenäisen sopeutumisen törmäysvapaaseen havainnointijärjestykseen. Osoitetaan, että ehdotettu strategia suppenee ja maksimoi kognitiivisen verkon kapasiteetin verrattuna satunnaiseen havainnointijärjestysten valintaan. Työn toisessa osassa pohditaan tilannetta, jossa hajautetut laitteet vuorovaikuttavat keskenään yhteistyössä suorittaakseen tehtäviään tai parantaakseen verkon resurssien käytön tehokkuutta. Peliteoreettisia työkaluja koalitioiden muodostamiseen mukautetaan dynaamisten yhteistoiminnallisten strategioiden laatimiseen hajautetuille laitteille. Dynaamisia koalitioiden muodostamismenetelmiä ehdotetaan kahteen erilaiseen verkkoskenaarioon: 1) hajautetut laitteet toimivat häiriöllisessä kanavassa, 2) hajautetut laitteet suorittavat spektrin havainnointia. Havaitaan, että jos hajautetussa spektrin havainnoinnissa laitteet tavoittelevat päämääriään itsekkäästi, niin koalitioiden muodostaminen voi johtaa alioptimaaliseen tasapainotilaan, jossa laitteet keskinäisen vaikutuksensa kautta saavuttavat verkon näkökulmasta epätoivotun koalitiorakenteen. Ehdotettua itsekästä mallia dynaamiseen koalitioiden muodostamiseen laajennetaan ottamaan selville, miten laitteiden koalitiokäyttäytyminen muuttuu, jos koalitioiden muodostaminen ei ole täydellisen itsekästä. Havaitaan, että hajautetun spektrin havainnoinnin probleemassa, keskimääräinen laitekohtainen kapasiteetti kasvaa kun laitteet tekevät yhteistyötä maksimoidakseen ryhmän kokonaishyödyn verrattuna siihen, jos ne tekevät yhteistyötä lisätäkseen yksittäisiä etujaan. Työn viimeisessä osassa pohditaan sensorien valintaongelmaa. Siinä ehdotetaan erilaisia menetelmiä, jotka valitsevat parhaan suorituskyvyn omaavat laitteet ja näytetään, että ehdotetut laitteiden valintamenetelmät pystyvät tarjoamaan merkittäviä suorituskykyetuja verrattuna satunnaiseen laitteiden valintaan
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Bodin, Ida. "Cognitive work analysis in practice : Adaptation to project scope and industrial context." Licentiate thesis, Uppsala universitet, Avdelningen för visuell information och interaktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-284334.
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The Cognitive Work Analysis (CWA) framework is widely used by researchers for the analysis of complex systems. It, however, lacks the same impact amongst industrial practitioners. This thesis investigates possible adaptations of the framework to project and industrial constraints, and the consequences associated with such adaptations. Long haul heavy vehicle transportation is the application domain for the work presented in the thesis. The CWA framework has been applied within the Methods for Designing Future Autonomous Systems (MODAS) project. Adaptations have been made to fit the framework within the project constraints and the industrial contexts. Interviews with stakeholders in an industrial organization regarding possible use of models from the CWA framework have been made. The CWA was scaled to available resources when applied within the MODAS project. From this we realized that prioritization of work activity can have consequences on the resulting systems ability to handle unforeseen events. Further, a focus on the current system probed a rapid out-dating of the analysis due to technical development. The conclusion is that even if advantages are lost during adaptation due to practical constraints, the CWA framework could add value to practitioners within industry if adapted to the industrial context.
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Franzén, Esbjörn. "Cognitive Differences, Adaptation and Disabilities : A Study in Extra-Ordinary Human-Computer Interaction." Thesis, University of Skövde, Department of Computer Science, 1997. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-288.
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This thesis concerns the relationship between aspects of cognitive differences and interface design in the context of visual impairment. Among a number of sources of cognitive differences studied, this work focuses on Witkin’s Cognitive Style Theory (1971). According to this theory people are more or less field-dependent. A field-independent person has good analytical and restructuring skills while the field-dependent individual has a more holistic approach and good inter-personal skills. According to several researchers, a number of design aspects such as dialogue style, user versus system guiding etc., can be designed to accommodate these differences in cognitive style. An interview study gives some support to the hypothesis that this relationship between cognitive style and design aspects also is relevant in a context of visual impairment.
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Al, Salman Ahmed Saeed Ali. "The Saudi Arabian Adaptation of the Addenbrooke's Cognitive Examination – Revised (Arabic ACE-R)." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4706/.
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BACKROUND: The population of the Arab World is about 300 million and the Arabic language is one of the six official languages of the United Nations. As with the rest of the world, degenerative neurological conditions represent a major health problem in regions such as the Middle-East where Arab people are in the majority. However, clinical neuropsychology is still in its infancy in this region. Very few tools for the assessment of cognition have been developed for use with Arabic speakers in the Middle-East region. The Addenbrooke's Cognitive Examination – Revised is a brief cognitive assessment tool that has been well validated in its original English version as well as a number of other languages, but never been adapted for use with Arabic speakers. An important issue for the assessment of cognition in this region is the high level of illiteracy, particularly in older adults, making the development of tools that can be used with both literate and illiterate participants a priority. OBJECTIVES: The studies presented in this thesis involved the translation, adaptation and validation of an Arabic Addenbrookes Cognitive Examination- Revised (ACE-R) and involved data collection from both literate and iliterate participants. METHODS: The ACE-R was translated into Arabic and the process is described in Chapter 2. Critical to the process was the cultural adaption of the test items. Three parallel versions were developed. Data was collected from four participant samples, recruited in Riyadh, Saudi Arabia: (1) Healthy literate (N= 147); (2) Healthy illiterate (N= 283); (3) Literate with a diagnosis of Alzheimer’s disease (AD) or Mild Cognitive Impairment (MCI) (N= 54); (4) Illiterate with a diagnosis of AD or MCI (N= 169). Chapter 3 presents a study of the validity of the Arabic ACE-R in literate participants. Receiver operating curve (ROC) analyses were undertaken to determine the sensitivity and specificity of the Arabic ACE-R to MCI/dementia, as well as positive and negative predictive values. Optimal cut-off scores were determined. Chapter 4 presents a study of the reliability of the Arabic ACE-R with literate participants. Parallel forms of the Arabic ACE-R were administered on two occasions separated by approximately one week. Test-retest and internal reliability (Cronbach’s alpha) were examined. A version of the test was developed for use with non-literate participants and Chapter 5 presents a study of its validity with this population. Chapter 6 reports a study of the reliability of the tool with non-literate participants. Chapter 7 reports normative data for the Arabic ACE-R, identifying fifth percentile cut-off points. RESULTS: Literate participants: Amongst healthy controls Arabic ACE-R data were not normally distributed, hence non-parametric statistics used in analyses. Amongst healthy controls age was correlated with Arabic ACE-R performance (rho = -0.568, p<0.0001) and level of education was also correlated with Arabic ACE-R performance (rho = 0.559, p<0.0001). As there was a significant difference in age between healthy controls and patient groups, groups were matched for age by removal of young controls and participants also examined in three age bands. Groups were matched for level of education. There were significant differences between each of the three groups examined – Mild Cognitive Impairment, Dementia of the Alzheimer’s type and healthy controls. As the MCI group was small, Receiver Operating Curve (ROC) analyses were conducted on the combined MCI/DAT group compared with the healthy control group. Levels of sensitivity/specificity were high. For a cut-off point of 70, sensitivity was 1.000 and specificity was 0.946. The positive and negative predictive values (PPV and NPV) were also high, particular for base rates that are likely to be closer to those found in clinical practice. For literate participants, internal reliability was high (Cronbach’s alpha, 0.932) as was total score test-retest reliability (rho=0.944). Individual subscale reliability ranged from rho=0.685 (Fluency) to rho=0.865 (Memory). Illiterate participants: Amongst healthy controls Arabic ACE-R data was not normally distributed, hence non-parametric statistics were used again. Amongst healthy controls age was correlated with Arabic ACE-R performance (rho = -286, p<0.001). As there was a significant difference in age between healthy controls and patient groups, groups were matched for age by removal of young controls and participants were also examined in three age bands. At a group level the data showed that there was a significant difference going from healthy to MCI and from MCI to DAT groups. ROC analyses showed that the Arabic ACE-R distinguished well between the healthy controls and patients with a diagnosis of either MCI or DAT. The optimum cut-off point on the Arabic ACE-R (65) had good sensitivity and specificity. Internal reliability was also high (Cronbach’s alpha, 0.987) as was total score test-retest reliability (rho=0.916), with individual sub-scale scores ranging from rho=0.647 (Language) to 0.861 (visuo-spatial). Analysis of normative data indicated the cut-off scores based on fifth percentile point results in somewhat higher cut-off points that those derived from ROC analyses, particularly for the younger literate participants. Potential reasons for these differences are discussed. CONCLUSION: The Arabic ACE-R shows good sensitivity and specificity in the detection of patients with a clinical diagnosis of either AD or MCI. This appears to be the case for both literate and illiterate participants. The Arabic ACE-R (Illiterate version) was straightforward to administer with just four tasks being omitted. This study only compared healthy controls and patients with clear evidence of dementia/MCI (and only small numbers of MCI). Because of the strong tradition of caring for older adults within families, and stigma associated with mental health problems, people with dementia are typically not referred to a doctor until the condition appears very clearly. Further research is needed to examine participants in earlier stages of disease and also participants with psychological/mood disorder. The Arabic ACE-R appears to be a reliable instrument for the assessment of cognitive impairment that may be arising from a degenerative neurological condition for both literate and illiterate participants.
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Gonzalez, Aleesandria. "EVALUATING THE COGNITIVE DRIVERS AND DETERRENTS OF ADAPTATION IN THE IOWA-CEDAR WATERSHED." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2105.
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This research explores the relationship between the cognitive variables perceived risks, perceived barriers, perceived self-efficacy, and perceived hazard experience with farmer support for adaptation and the agreement between farmer perceptions with observed climate conditions of drought and excess precipitation. Climate conditions were evaluated using monthly Standardized Precipitation-Evapotranspiration Index (SPEI) values from 1950 to 2014. The remaining variables were measured using a closed ended survey of corn and soybean farmers (N =276) in the Iowa-Cedar Watershed. The relationships were evaluated using Spearman’s Rank Order Correlation (), frequency distributions, and probability analysis. Perceived barriers were found to be a significant predictor of support for adaptation. Transformational adaptations were less supported by farmers than incremental adaptations. Farmers expressed more concern for finances than any other risks or barrier. The majority of farmers reported low to moderate risks to drought and precipitation with high efficacy to cope to future impacts. Lastly, climate conditions indicate that there were more frequent and extreme precipitation events than drought events and that farmer perceptions of climate are consistent with observed climate conditions. However, while climate change projections indicate increased weather extremes in the future, farmers perceive no change in risks. It is unclear whether or not farmers are actually equipped to handle future threats to their crops. Future research should address this problem by conducting a longitudinal study to observe farmers’ perception prior to and after experiencing extreme events.
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Popescu, Alexandru. "Cognitive Radio Networks : Elements and Architectures." Doctoral thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00575.
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As mobility and computing becomes ever more pervasive in society and business, the non-optimal use of radio resources has created many new challenges for telecommunication operators. Usage patterns of modern wireless handheld devices, such as smartphones and surfboards, have indicated that the signaling traffic generated is many times larger than at a traditional laptop. Furthermore, in spite of approaching theoretical limits by, e.g., the spectral efficiency improvements brought by 4G, this is still not sufficient for many practical applications demanded by end users. Essentially, users located at the edge of a cell cannot achieve the high data throughputs promised by 4G specifications. Worst yet, the Quality of Service bottlenecks in 4G networks are expected to become a major issue over the next years given the rapid growth of mobile devices. The main problems are because of rigid mobile systems architectures with limited possibilities to reconfigure terminals and base stations depending on spectrum availability. Consequently, new solutions must be developed that coexist with legacy infrastructures and more importantly improve upon them to enable flexibility in the modes of operation. To control the intelligence required for such modes of operation, cognitive radio technology is a key concept suggested to be part of the so-called beyond 4th generation mobile networks. The basic idea is to allow unlicensed users access to licensed spectrum, under the condition that the interference perceived by the licensed users is minimal. This can be achieved with the help of devices capable of accurately sensing the spectrum occupancy, learning about temporarily unused frequency bands and able to reconfigure their transmission parameters in such a way that the spectral opportunities can be effectively exploited. Accordingly, this indicates the need for a more flexible and dynamic allocation of the spectrum resources, which requires a new approach to cognitive radio network management. Subsequently, a novel architecture designed at the application layer is suggested to manage communication in cognitive radio networks. The goal is to improve the performance in a cognitive radio network by sensing, learning, optimization and adaptation.
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Bellasfar, Souhir. "Dépression et flexibilité cognitive : le cas des personnes âgées." Thesis, Lyon 2, 2009. http://www.theses.fr/2009LYO20106.
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Ce travail est une contribution à la compréhension des capacités adaptatives des personnes âgées déprimées et non déprimées. Pour répondre à cet objectif nous avons utilisé une méthode expérimentale et une observation clinique : une étude de cas suivie longitudinalement pendant 6 ans. La relation dépression - flexibilité cognitive est évaluée au moyen d'épreuves de shifting et de fluence auprès de deux groupes de personnes âgées non démentes, déprimées et non déprimées, résidant en maisons de retraite.L'analyse quantitative et qualitative met en évidence un affaiblissement de la flexibilité cognitive qui se traduit par une corrélation négative entre les scores de dépression et ceux obtenus aux épreuves de flexibilité réactive et spontanée. Nous établissons une analogie entre les comportements adaptatifs au quotidien et les données quantitatives, et nous proposons un schéma théorique expliquant le comportement adaptatif des personnes âgées. Notre étude de cas permet une meilleure compréhension de la relation dépression-flexibilité cognitive notamment l'amélioration des capacités adaptatives suite à la baisse du niveau de dépressionThis thesis is a contribution to the understanding of adaptive capacity of depressed and non-depressed aging adults. To achieve this goal we have used an experimental method and a clinical observation: a six-year longitudinal case study. The relationship between depression and cognitive flexibility is assessed by means of shifting and fluency tasks applied to two groups of non-dement depressed and non-depressed elderly who reside in nursing institutions.The quantitative and qualitative analysis shows a decrease in cognitive flexibility which highlights a negative correlation between depression and flexibility scores. We establish an analogy between daily adaptive behaviours and quantitative data, and we propose a theoretical mechanism that explains the adaptive behaviour of the elderly. Our case study offers a deeper understanding of the relationship between depression and cognitive flexibility, particularly the improvements of adaptive capacities due to a decrease of depression
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Kuhns, David. "Conflict and Control: How Does the Brain Regulate Cognitive Control in the Presence of Conflict?" Thesis, University of Oregon, 2014. http://hdl.handle.net/1794/18500.
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Cognitive control refers to the brain's ability to control attention and other cognitive functions in the service of intention-driven behaviors; moreover, it is an essential aspect in cognition. Cognitive control is commonly evaluated through the so-called conflict adaptation effect, which is revealed through trial-to-trial changes in performance after experiencing cognitive conflict. The conflict monitoring theory is a prominent theory intended to describe conflict adaptation and explain how cognitive control might be engaged in the face of conflict. A passive carryover account, originally aimed at explaining task switching and based on parallel distributed processing models, may represent a superior alternative to the conflict monitoring account. In the carryover account, passive inertia of the cognitive control state explains the trial-to-trial modulation of conflict effects. One problem with conflict adaptation is that the typical paradigms used to create conflict adaptation often include trial-to-trial repetitions that mimic the same performance pattern through priming. Conflict monitoring theory also has difficulty explaining other issues such as whether conflict adaptation is task-specific. A meta-analysis of the so-called conflict adaptation effect suggests trial-to-trial repetitions do not entirely account for conflict adaptation effects, but these effects do appear to be task-specific. The meta-analysis also suggests the withdrawal of control is episodic rather than temporal and conflict adaptation may be sensitive to experimental session length. A novel eye-tracking paradigm addresses the timing of control engagement. The results suggest dynamic regulation of attention coupled with conflict detection. This more tightly coupled detection and regulation process in the context of conflict adaptation is more consistent with a carryover account than what would be expected from the conflict monitoring theory. A subsequent eye-tracking paradigm further supported that trial-to-trial modulations of control are generally more consistent with a carryover account than they are with the conflict monitoring theory. Overall, the empirical evidence points toward a carryover model of cognitive control.2016-10-17
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Feeman, Kelley Laurel. "ADAPTING IMAGINATION: A COGNITIVE THEORY FOR ADAPTING COMICS TO THE STAGE." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1564738881854803.
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FALCÃO, Marcos Rocha de Moraes. "Channel reservation and spectrum adaptation strategies in a multi-level prioritized cognitive radio network." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/21070.
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CAPES
Wireless technologies have dominated the communication's market by offering reasonable speeds and convenience at low deployment costs. However, due to the significant growth of mobile computing devices and their bandwidth demands, together with the paradigm shift brought by the Internet of things, future wireless networks should become highly dense and heterogeneous, which will hardly cope with the traditional fixed spectrum allocation policy. Some standards such as the Long Term Evolution – Advanced (LTE-A), have already set the precedent for carrier aggregation (CA), aiming at scaling up bitrates, which partially helps solving the problem. However, cognitive radio (CR) has been put forward as the most promising solution to handle this complex ecosystem since it may provide better spectrum utilization and user coordination through non-traditional mechanisms. Among other features, it allows non-licensed users, known as secondary users (SUs) to opportunistically use temporarily idle licensed bands that are used by licensed clients called primary users (PUs). Once PUs and SUs are expected to share the same spectrum bands, a critical issue is to concomitantly avoid primary interference while supporting QoS for the secondary services. This dissertation studies the synergistic integration of cognitive radio networks (CRNs), Dynamic Spectrum Access DSA techniques and resource allocation strategies (e.g., CA) that combined, should improve the overall system’s performance. We have proposed a layered M/M/N/N queue-based model that addresses three user priorities, flexible bandwidth choices, multi-level channel reservation and two channel aggregation strategies. Different network load conditions for each feature were evaluated in terms of four performance metrics: blocking probability, forced termination probability, spectrum utilization and throughput. Such study is particularly useful for understanding the effects of each of these approaches in the secondary network. To the best of our knowledge, our model fulfills almost completely the user bandwidth’s possibilities, improves the existing channel reservation formulation and demonstrates that our proposed dynamic channel aggregation strategy performs similarly to a more complex simultaneous channel aggregation and fragmentation approach, but can be technically more feasible.
Tecnologias sem fio têm dominado o mercado das comunicações, oferecendo velocidades razoáveis e conveniência a um baixo custo de implantação. No entanto, devido ao crescimento significativo do número de plataformas computacionais móveis e de suas demandas por largura de banda, acrescido do advento da Internet das Coisas, as redes sem fio do futuro devem passar a ser muito mais densas e heterogêneas, sendo difíceis de se adequar a política tradicional de alocação espectral fixa. Recentemente, o método de agregação de portadora (AP) fora proposto no padrão Long Term Evolution – Advanced (LTE-A), com o propósito de aumentar as taxas de bit, mitigando assim parte do problema. Todavia, rádio cognitivo (RC) foi apresentada como a solução mais promissora para lidar com este ecossistema complexo, uma vez que pode proporcionar uma melhor utilização do espectro e coordenação de usuários através de mecanismos não-tradicionais. Entre outras características, isso permite que usuários não-licenciados também conhecidos como usuários secundários (USs) utilizem de forma oportunista bandas licenciadas temporariamente ociosas, cujos clientes licenciados são também chamados de usuários primários (UPs). Como os UPs e os USs devem compartilhar as mesmas bandas, uma questão crítica é evitar interferência primária e concomitantemente apoiar a qualidade de serviço prestada aos USs. Esta dissertação estuda a integração sinérgica das redes de rádio cognitivas, técnicas de acesso dinâmico ao espectro e estratégias de alocação de recursos (AP), que combinados, devem melhorar o desempenho do sistema. Neste trabalho, propomos um modelo baseado em filas do tipo M/M/N/N, que inclui três prioridades de usuário, opções de largura de banda, reserva de canal multi-nível e duas estratégias de agregação de canal. Para cada recurso estudado, empregamos diferentes condições de carga de rede e avaliamos os resultados em termos de quatro métricas: probabilidade de bloqueio, a probabilidade de terminação forçada, utilização espectral e vazão. Este estudo é particularmente útil para compreender os efeitos de cada uma destas abordagens em relação à rede secundária. O modelo fornecido cumpre quase completamente as possibilidades do largura de banda de cada nível de usuário, melhora a formulação de reserva de canal existente e demonstra que estratégia de agregação de canais proposta possui performance similar a uma abordagem mais complexa de agregação e fragmentação simultânea, mas que seria tecnicamente mais viável.
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Unkrich, Diane Michelle. "Neuropsychological test adaptation into Greek a comparative study of cognitive-linguistic performance in older adults /." Oxford, Ohio : Miami University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1145306672.
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Gresley, Lucy. "Cognitive adaptation to the diagnosis of Asperger syndrome and the relationship with depression and adjustment." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432494.
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Styring, Nicola. "Examining the predictive utility of the theory of cognitive adaptation in relation to alopecia areata." Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434455.
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Unkrich, Diane. "Neuropsychological Test Adaptation Into Greek: A Comparative Study of Cognitive-Linguistic Performance in Older Adults." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1145306672.
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Merzlyak, Irina Y. "The Role of the basolateral amygdala in affective associative learning, arousal and adaptation." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3205363.
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Thesis (Ph. D.)--University of California, San Diego, 2006.Title from first page of PDF file (viewed April 4, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Press, Claire. "Developing culturally adapted cognitive remediation for South Asian first episode psychosis sufferers." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/developing-culturally-adapted-cognitive-remediation-for-south-asian-first-episode-psychosis-sufferers(9dd2210e-3587-4acc-986b-5f2121467ff5).html.
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Introduction: An increased incidence of schizophrenia among migrant and ethnic minority groups has been established. Ethnic minorities have poorer access to and outcomes from evidence based psychosocial interventions compared to the majority population. The overall aims of this thesis was to explore culturally adapted psychosocial interventions for migrant and ethnic minority schizophrenia sufferers, and use the results of these investigations to develop culturally adapted cognitive remediation (CR) to meet the needs of South Asian first episode sufferers. Methods: A systematic review and meta-analysis of previous randomised controlled trials (RCTs) investigated the quality, methods and effectiveness of culturally adapted psychosocial interventions for schizophrenia. Interviews, analysed using framework analysis, explored the acceptability, and perceived accessibility, of CR to the target population. CR for first episode psychosis was then adapted to target South Asian sufferers' needs and participants' satisfaction and engagement measured in a feasibility study. Results: The systematic review identified 17 RCTs of culturally adapted psychosocial interventions for schizophrenia. Meta-analysis of culturally adapted Family Intervention (caFI) compared to Treatment As Usual (TAU) showed no reduction in relapse risk. There were non-significant reductions in risk and number of hospitalisations during the intervention and significant shortening of total time in hospital. Meta-analysis of culturally adapted Social Skills Training (caSST), compared to TAU showed improvements in medication and symptom management but no effects when compared to a time-matched psychosocial intervention. Results must be interpreted with caution due to the small number of trials included and limitations in their analyses. Cultural adaptations made to the interventions were similar across trials. This allowed for the development of a measure systematically recording the methods used in culturally adapting interventions. Scale items included: language, therapeutic alliance, teaching style, manual content, family, treatment goals, explanatory models of illness, help seeking behaviour, delivery, stigma, societal context and cultural tenets. Emergent themes from qualitative interviews with ten South Asian first episode schizophrenia sufferers included: help seeking for psychosis, sociocultural influences on help seeking, experience of cognitive deficits, and recommended cultural adaptations to CR. CR was well received by all respondents. Level of acculturation and the influence of family and illness beliefs were associated with distinct pathways to care. A feasibility study of culturally adapted cognitive remediation (caCR) for first episode South Asian psychosis patients resulted in high levels of service user satisfaction, therapeutic alliance and participant retention rates. The majority (87.5%) reported cognitive benefits and a boost in self-esteem. Conclusions: The scale of cultural adaptations for psychosocial interventions for schizophrenia will provide a framework for those developing culturally adapted interventions for migrant or ethnic minority communities and a means to record the degree and type of adaptation. CaCR was acceptable to first episode South Asian psychosis sufferers. A larger trial is required to investigate this intervention's efficacy in terms of cognitive and global functioning.
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McNamara, Anne Margaret. "Cognitive response to symptoms in women with rheumatoid arthritis." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185754.
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The purpose of this study was to advance knowledge and understanding related to the cognitive response evoked by symptoms in women with rheumatoid arthritis. The mechanisms to achieve this purpose were through: (1) psychometric evaluation of a newly developed instrument: Chronic Fatigue Index (CFI), (2) examining the relationship among the symptoms of RA and components of quality of life for women with RA, and (3) exploring the mechanism by which learned resourcefulness affects the relationship between symptoms and quality of life. The Chronic Fatigue Index (CFI) was evaluated and met minimal levels of reliability and validity. Cronbach alpha reliability estimate for the CFI was.87. Convergent validity was tested through factor analysis. The CFI was found to be a multi-dimensional scale with two distinct factors: chronicity and interference. The factor analytical strategies revealed 46% of the variance in chronic fatigue was supported by these two components. Moderate to strong relationships were found among the symptoms of chronic pain, chronic fatigue, disturbed sleep, and disease flare. To evaluate quality of life in this population a common factor was created through factor analysis. The results of factor analysis revealed three indicators explaining 69% of the variance in quality of life for this population. Chronic pain explained fourteen percent of the variance in learned resourcefulness. The other symptoms and multiplicative terms did not meet the entry criteria. Learned resourcefulness was a weak mediator between the disturbance of chronic pain and quality of life, but successfully moderated the adverse effect of disturbed sleep. Fifty eight percent of the variance in quality of life was explained by the direct path of chronic pain and disturbed sleep on quality of life and the interaction of disturbed sleep and learned resourcefulness. Model respecification suggested that the inclusion of additional variables in the model would increase the explanatory power of the model. The self-regulation framework for symptom appraisal was supported by the findings of this study. Nursing interventions should focus on assisting clients with enhancing their level of learned resourcefulness as it will buffer the adverse effects of the disease process.
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Kashefi, Armin. "Investigating the link between users' IT adaptation behaviours and individual-level IT use outcomes using the coping model of user adaptation : a case study of a work system computerisation project." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/9523.
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The benefits of new IT-induced organisational changes, such as new organisational information systems (IS), depend on the degree that system users adapt by proactively changing themselves, their work routines, and even the technology itself in order to reap its strategic capabilities and advantages. However, researchers are increasingly concerned that IS research has provided very little indication about how IS users’ IT adaptive strategies are formed and evolved over time and how such adaptive behaviours employed by IS users influence subsequent IT use and individual-level performance outcomes. This thesis investigates in-depth the evolution of IT adaptation behaviours towards disruptive IT events in the case study of a Medical Clinic attached to one of Iran’s elite Oil and Gas industry companies. The case study investigated the individual coping behaviours of the employees of this Medical Centre as a consequence of the introduction of a mandatory Work System Computerisation (WSC) initiative. Work System Computerisation project refers to both the replacement of manual work processes with computers as well as modernisation of the existing out-dated computerised work systems in the medical centre under investigation. According to the case study, each of the seven sub-units of the Medical Centre implemented a different WSC scheme and the consequences of the introduction of the scheme resulted in differing outcomes among the employees of those sub-units, such outcomes being related to a complex interplay of the individuals’ coping behaviours, appraisals and emotional responses and the environment. The term ‘Disruptive IT event’ in this study refers to any enhanced or completely new information technology in different units within the medical centre (i.e. Work System Computerisation schemes) that replaced and disrupted existing work processes/practices and had resulted in disruptive and unpredictable changes to users’ daily routines. The theoretical lens used in this study is the Coping Model of User Adaptation (CMUA) elaborated by Coping Theory, which also underpins the model. CMUA provides a useful theoretical basis for deeper understanding of users’ adaptive responses to a new work information system (IS) as well as direct analysis of the impact of such adaptive responses on system usage. The other theoretical concept used, which addresses issues not readily covered by the CMUA, was a typology of adaptive behaviours from Roth and Cohen (1986): avoidance vs. approach. This allows for further clarification of how different types of individual-level adaptation acts evolve over time and affect individual-level IT use outcomes. Furthermore, how these various adaptive acts enhance or hinder the extent to which the new IT is used can also be explained. The research questions guiding this thesis are as follows: (1) How do IS users’ adaptation tactics and strategies evolve over time when dealing with a disruptive IT event? (2) How do alterations in users’ coping strategies subsequently influence their IT use outcomes and overall performance? The study’s methodological approaches and underlying philosophical assumptions followed an interpretive research approach. A broadly interpretive approach was adopted in this study with the aim of understanding the complexity of human sense making and their IT adaptation behaviours as the situation emerges. The research was carried out in one state of Iran, Mashhad, and took place during the period of 2011-2012. The findings of this thesis have both theoretical and managerial implications. From a theoretical perspective, this study expands on the work of Beaudry and Pinsonneault (2005) who suggested that the process of user adaptation could be understood in light of coping theory. The results of this study and the additional identified perspectives and enhancements which are represented in the following ways could help to advance the field of user IT adaptation behaviours in IS research. This study contributes to the existing IT adaptation literature by providing rich insights into the phenomenon of user IT adaptation behaviours within the context of Iran. Adopting an interpretive approach through a longitudinal process-oriented perspective has provided a greater understanding of the patterns of user adaptation to IS, users’ psychological constructs, initial patterns of their coping strategies, the alterations in such coping efforts over time, and the consequences of these evolutions on IT use outcomes in different divisions within a healthcare environment. The appraisal of ‘challenge’ is an influential contributor to the users’ subsequent adaptation process that CMUA is mute about it. The findings indicate that since the challenge appraisal represents a ‘positive stress’, some levels of challenge are useful to mobilise IS users towards IT adoption and use. The correlated concerns identified in the research (i.e. a web of complex personal, social and technical concerns) play a vital role on users’ adaptation processes following the IT implementation and over time. This highlights the importance of feedback loop in the adaptation process (which represents users’ revaluation process), and how the direct and indirect impacts of such interventions affect users’ reassessments of the IT event and their subsequent efforts and outcomes. The concept of emotion that is missing from CMUA is influential especially where non-IT savvy users’ behaviours toward significant IT events may be influenced by extreme emotions. Outcomes of this study highlight the theoretical importance of preserving the distinction between approach-, and avoidance-oriented emotion-focused behaviours in exploring how emotion-focused behaviours may influence behavioural outcomes such as system usage. The consideration of parallel processes for users’ IS appraisal is another area of theoretical expansion. The findings also suggest implications for practice as well as directions for future research. Understanding how employees’ IS appraisals considerably affect coping efforts and ultimately their technology performance outcome is critical for successful IT implementations and use in work settings. The results could assist decision makers in assessing user adaptation concerns and the intensity of such apprehensions at each phase of the change process and hence address them more effectively.
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Hardesty, Vincent H. "A Study to Investigate the Cognitive Changes that Occur Following Keto-Adaptation and Resistance Training in Healthy Adults." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523890686805261.
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Vargas, Sara. "Does Sleep Mediate Improvements in Functional Adaptation After a Stress Management Intervention For Women With Breast Cancer?" Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_theses/288.
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The time of cancer diagnosis and treatment may be marked by an increase in stressors, which may be associated with poorer psychosocial and physical adaptation and increased sleep difficulty. Prior work has shown that psychosocial interventions that teach stress management skills can improve indicators of psychosocial and physical adaptation in women with breast cancer, mostly in cancer survivors who have completed treatment. The extant literature does not examine the effects of stress management on sleep, or the role that sleep plays in mediating psychosocial and physical adaptation outcomes, among women in the midst of treatment for non-metastatic breast cancer (BCa). Two hundred forty (240) women, recruited post-surgery from oncology practices, were randomly assigned to a 10-week group-based cognitive behavioral stress management intervention (CBSM; n = 120) or 1-day psychoeducation (PE) control (n = 120). The intervention consisted of didactics, CBSM techniques, and relaxation exercises, but did not specifically target sleep or sleep quality (SQ). Women assigned to the PE condition attended a one-day group seminar where they learned some of the material covered in the CBSM intervention, without the therapeutic group environment, role play techniques, and home practice. Participants completed self-report questionnaires at baseline, and at 6- and 12-month follow-ups. After controlling for days since surgery, participants in the CBSM group reported improved SQ, as well as increased positive states of mind, decreased disruption in social recreational functioning, and reduced fatigue-related daytime dysfunction for up to 8 - 12 months after baseline. There were marginally significant improvements in functional well-being and social functioning. CBSM was not associated with improvements in fatigue intensity. Improvements in SQ mediated CBSM-associated improvements in positive states of mind, social disruption, and fatigue-related daytime dysfunction. Thus, the CBSM intervention had beneficial effects on several indicators of functional adaptation that were in part explained by improvements in the quality of sleep. Future work should test the combined effects of stress management and sleep management interventions for women initiating treatment for BCa.
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Littman, Eric Marshall. "Adaptation to Simultaneous Multi-Dimensional Distortions." Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1311961424.
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Dreisbach, Gesine, and Rico Fischer. "Conflicts as Aversive Signals for Control Adaptation." Sage, 2015. https://tud.qucosa.de/id/qucosa%3A35475.
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The dynamic adaptation of cognitive control in the face of competition from conflicting response tendencies is one of the hallmarks of flexible human action control. Here, we suggest an alternative framework that places conflicttriggered control adaptation into the broader context of affect regulation. Specifically, we review evidence showing that (a) conflicts are inherently aversive, that (b) aversive stimuli in the absence of conflict also trigger behavioral adjustments, and, finally, that (c) conflict stimuli do trigger processes of affective counter-regulation. Together with recent findings showing that conflict-triggered control adaptation depends on the subjective experience of the conflict, we suggest that it is the subjective aversive conflict experience that originally motivates control adaptations. Such a view offers new perspectives for investigating and understanding intra- and interindividual differences in the regulation of cognitive control by differentiating between the individual sensitivity to experience and the individual ability to utilize the aversive signal.
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Machando, Debra. "Neurocognitive screening following acquired brain injury: an adaptation of the Birmingham Cognitive Screen for Zimbabwe (Zim-BCoS)." Doctoral thesis, Faculty of Humanities, 2021. http://hdl.handle.net/11427/32763.
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Neuropsychology as a discipline has not taken root in low- and middle-income countries. Most neurocognitive tests used in these countries were developed and normed in high-income, mostly western countries. The psychometric robustness of these tests is often weak when they are used on low to middle-income clinical populations. The objectives of this study were to select, adapt and generate normative data for a suitable neurocognitive screen for use in Zimbabwe. To achieve these objectives, we divided the study into 4 phases. In Phase 1 of the study, we did a systematic review that identified 83 neurocognitive assessment instruments commonly used in low- and middle-income countries on patients who have suffered a stroke. From these instruments, we selected, adapted and normed the Birmingham Cognitive Screen (BCoS; Humphreys al., 2012) through phases 2 to 4 of this study. The screen offers a robust and sufficiently broad but shallow assessment tool for cognitive deficits across key cognitive domains commonly impaired following a stroke. In particular, in Phase 2 of the study, we evaluated the cross-cultural sensitivity of BCoS on healthy participants (N=105). We then performed surveys using the Delphi method on a panel of experts to culturally adapt BCoS for use in Zimbabwe (Zim-BCoS). We evaluated the inter-rater and test-retest reliability of the translated and validated Zim-BCoS and also compared its agreement with the original BCoS version to determine its robustness. In Phase 3, we evaluated the effects of demographic variables on performance on the cognitive domains assessed by Zim-BCoS. To do this, we performed multiple linear regression analyses to calculate regression-based norms using scores from a sample of healthy participants (N=412). From these analyses, participants' age, level of education and sex had significant effects, mainly on subtests in the language cognitive domain (Picture Naming, Sentence/Word Reading/Writing and Instruction Comprehension). In Phase 4 of the study, we performed neurocognitive assessments using Zim-BCoS (and other tests) to assess and determine the frequency of specific neurocognitive deficits in patients who had suffered a stroke and were attending two major hospitals in Harare, Zimbabwe's capital city (N=103). We also compared the performance of these patients to a matched control sample (N=103). To determine the psychometric stability of Zim-BCoS we determined its validity and reliability by comparing scores on its subtests to parallel neurocognitive tests that assess similar cognitive domains. We also assessed the predictive value of Zim-BCoS on patients' neuropsychiatric and functional outcomes. We evaluated the convergence and predictive validity as well as the inclusivity of Zim-BCoS to assess patients with aphasia. We used the Zim-BCoS test scores to establish prevalence rates of cognitive deficits and other post-stroke sequelae in the sample of patients with stroke. We also assessed the predictive value of ZimBCoS subtests on patients' neuropsychiatric and functional outcomes. All comparisons of ZimBCoS against standard cognitive tests and post-stroke sequelae measures had statistically significant convergence, predictive validity and inclusivity. In this study, we demonstrated the utility of Zim-BCoS for assessing cognitive impairment in patients who have suffered a stroke, particularly in resource poor contexts typical of low-income countries. We concluded that ZimBCoS is a robust neuropsychological screen suitable for research and clinical use in Zimbabwe. The screen has the potential to offer a cost effective and easy to use neurocognitive screen for patients with acquired neurological changes in low-income countries in Southern Africa.
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Heath, Jennifer. "Self-reported quality of life and cognitive adaptation in children and young people with chronic kidney disease." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/9261/.
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Literature review: Seventeen studies utilising the Child Attitude Toward Illness Scale (Austin & Huberty, 1993) in paediatric research were reviewed. The review found that a range of biopsychosocial factors (e.g. condition severity, depression, worry, self-efficacy, family functioning) were associated with attitude toward illness. It is theoretically and clinically important to further understand the nature of these relationships through the development of well-designed studies and theoretical models. Assessment of children’s attitudes towards their illness in clinical and research settings will provide greater understanding of the impact of chronic illness and aid development of appropriate interventions. A number of methodological limitations exist in this area of research that reduces the strength of conclusions that can be drawn. Research report This cross-sectional study measured the generic and health-related quality of life (QoL) and attitude towards illness of 72 children aged six to 18 with chronic kidney disease (CKD). Generic QoL for patients was comparable with previously collected norms. CKD stage, age, time since diagnosis, and time receiving current treatment were unrelated to the outcomes. There was no impact of gender on QoL but males had more negative illness attitudes than females. Pre-emptive transplant patients rated both generic and health-related QoL higher than those in other treatment groups did, but there were no treatment effects on illness attitudes. Findings are discussed in relation to previous research that has predominantly focused on health-related QoL in paediatric patients. Recommendations for future research are made and the clinical and theoretical implications for practice are described.
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John-Baptiste, Peter Jr. "Advancing Fully Adaptive Radar Concepts for Real-Time Parameter Adaptation and Decision Making." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595501564082873.
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Yücek, Tevfik. "Channel, spectrum, and waveform awareness in OFDM-based cognitive radio systems." Scholar Commons, 2007. http://scholarcommons.usf.edu/etd/2425.
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The radio spectrum is becoming increasingly congested everyday with emerging technologies and with the increasing number of wireless devices. Considering the limited bandwidth availability, accommodating the demand for higher capacity and data rates is a challenging task, requiring innovative technologies that can offer new ways of exploiting the available radio spectrum. Cognitive radio arises to be a tempting solution to the spectral crowding problem by introducing the notion of opportunistic spectrum usage. Because of its attractive features, orthogonal frequency division multiplexing (OFDM) has been successfully used in numerous wireless standards and technologies. We believe that OFDM will play an important role in realizing the cognitive radio concept as well by providing a proven, scalable, and adaptive technology for air interface. The goal of this dissertation is to identify and address some of the challenges that arise from the introduction of cognitive radio.
Specifically, we propose methods for obtaining awareness about channel, spectrum, and waveform in OFDM-based cognitive radio systems in this dissertation. Parameter estimation for enabling adaptation, spectrum sensing, and OFDM system identification are the three main topics discussed. OFDM technique is investigated as a candidate for cognitive radio systems. Cognitive radio features and requirements are discussed in detail, and OFDM's ability to satisfy these requirements is explained. In addition, we identify the challenges that arise from employing OFDM technology in cognitive radio. Algorithms for estimating various channel related parameters are presented. These parameters are vital for enabling adaptive system design, which is a key requirement for cognitive radio. We develop methods for estimating root-mean-square (RMS) delay spread, Doppler spread, and noise variance.
The spectrum opportunity and spectrum sensing concepts are re-evaluated by considering different dimensions of the spectrum which is known as multi-dimensional spectrum space. Spectrum sensing problem in a multi-dimensional space is addressed by developing a new sensing algorithm termed as partial match filtering (PMF). Cognitive radios are expected to recognize different wireless networks and have capability of communicating with them. Algorithms for identification of multi-carrier transmissions are developed. Within the same work, methods for blindly detecting transmission parameters of an OFDM based system are developed. Blind detection is also very helpful in reducing system signaling overhead in the case of adaptive transmission where transmission parameters are changed depending on the environmental characteristics or spectrum availability.
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Geraghty, Jennifer. "Mobility changes in older age : neuropsychological, neurophysiological and cognitive predictors of successful adaptation in a real world scenario." Thesis, Aston University, 2016. http://publications.aston.ac.uk/28638/.
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The aims of this thesis were to investigate the neuropsychological, neurophysiological, and cognitive contributors to mobility changes with increasing age. In a series of studies with adults aged 45-88 years, unsafe pedestrian behaviour and falls were investigated in relation to i) cognitive functions (including response time variability, executive function, and visual attention tests), ii) mobility assessments (including gait and balance and using motion capture cameras), iii) motor initiation and pedestrian road crossing behavior (using a simulated pedestrian road scene), iv) neuronal and functional brain changes (using a computer based crossing task with magnetoencephalography), and v) quality of life questionnaires (including fear of falling and restricted range of travel). Older adults are more likely to be fatally injured at the far-side of the road compared to the near-side of the road, however, the underlying mobility and cognitive processes related to lane-specific (i.e. near-side or far-side) pedestrian crossing errors in older adults is currently unknown. The first study explored cognitive, motor initiation, and mobility predictors of unsafe pedestrian crossing behaviours. The purpose of the first study (Chapter 2) was to determine whether collisions at the near-side and far-side would be differentially predicted by mobility indices (such as walking speed and postural sway), motor initiation, and cognitive function (including spatial planning, visual attention, and within participant variability) with increasing age. The results suggest that near-side unsafe pedestrian crossing errors are related to processing speed, whereas far-side errors are related to spatial planning difficulties. Both near-side and far-side crossing errors were related to walking speed and motor initiation measures (specifically motor initiation variability). The salient mobility predictors of unsafe pedestrian crossings determined in the above study were examined in Chapter 3 in conjunction with the presence of a history of falls. The purpose of this study was to determine the extent to which walking speed (indicated as a salient predictor of unsafe crossings and start-up delay in Chapter 2), and previous falls can be predicted and explained by age-related changes in mobility and cognitive function changes (specifically within participant variability and spatial ability). 53.2% of walking speed variance was found to be predicted by self-rated mobility score, sit-to-stand time, motor initiation, and within participant variability. Although a significant model was not found to predict fall history variance, postural sway and attentional set shifting ability was found to be strongly related to the occurrence of falls within the last year. Next in Chapter 4, unsafe pedestrian crossing behaviour and pedestrian predictors (both mobility and cognitive measures) from Chapter 2 were explored in terms of increasing hemispheric laterality of attentional functions and inter-hemispheric oscillatory beta power changes associated with increasing age. Elevated beta (15-35 Hz) power in the motor cortex prior to movement, and reduced beta power post-movement has been linked to age-related changes in mobility. In addition, increasing recruitment of both hemispheres has been shown to occur and be beneficial to perform similarly to younger adults in cognitive tasks (Cabeza, Anderson, Locantore, & McIntosh, 2002). It has been hypothesised that changes in hemispheric neural beta power may explain the presence of more pedestrian errors at the farside of the road in older adults. The purpose of the study was to determine whether changes in age-related cortical oscillatory beta power and hemispheric laterality are linked to unsafe pedestrian behaviour in older adults. Results indicated that pedestrian errors at the near-side are linked to hemispheric bilateralisation, and neural overcompensation post-movement, 4 whereas far-side unsafe errors are linked to not employing neural compensation methods (hemispheric bilateralisation). Finally, in Chapter 5, fear of falling, life space mobility, and quality of life in old age were examined to determine their relationships with cognition, mobility (including fall history and pedestrian behaviour), and motor initiation. In addition to death and injury, mobility decline (such as pedestrian errors in Chapter 2, and falls in Chapter 3) and cognition can negatively affect quality of life and result in activity avoidance. Further, number of falls in Chapter 3 was not significantly linked to mobility and cognition alone, and may be further explained by a fear of falling. The objective of the above study (Study 2, Chapter 3) was to determine the role of mobility and cognition on fear of falling and life space mobility, and the impact on quality of life measures. Results indicated that missing safe pedestrian crossing gaps (potentially indicating crossing anxiety) and mobility decline were consistent predictors of fear of falling, reduced life space mobility, and quality of life variance. Social community (total number of close family and friends) was also linked to life space mobility and quality of life. Lower cognitive functions (particularly processing speed and reaction time) were found to predict variance in fear of falling and quality of life in old age. Overall, the findings indicated that mobility decline (particularly walking speed or walking difficulty), processing speed, and intra-individual variability in attention (including motor initiation variability) are salient predictors of participant safety (mainly pedestrian crossing errors) and wellbeing with increasing age. More research is required to produce a significant model to explain the number of falls.
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Renga, Sandra. "An evaluation of two predictive models of adjustment in women with breast cancer : hope versus cognitive adaptation theory." Thesis, Lancaster University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442721.
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Celebi, Hasari. "Location awareness in cognitive radio networks." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002562.
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Bouallegue, Kaïs. "Contribution à la radio intelligente à forte mobilité : adaptation spectrale et allocation dynamique des ressources." Thesis, Valenciennes, 2017. http://www.theses.fr/2017VALE0023.
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Les objectifs essentiels des opérateurs ferroviaires sont d'augmenter la sécurité, de réduire les coûts d'exploitation et de maintenance, d'accroître l'attrait et le profit en offrant de nouveaux services aux passagers. Ces objectifs seront atteintsgrâce à une énorme augmentation des échanges de flux de données entre les infrastructures existantes et les technologies présentes utilisées au bord du train. L'efficacité spectrale, l'optimisation des ressources radioélectriques ainsi que l'interopérabilité mais aussi la fiabilité des communications sont des éléments majeurs pour les applications ferroviaires. Ces contraintes ainsi que l'utilisation sporadique des bandes fréquentielles à disposition ont donné le jour à la radio intelligente. Cette dernière se présente comme une technologie émergente qui améliore les performances des systèmes radio existants en intégrant l'intelligence artificielle avec la radio logicielle. Un système radio intelligent est défini par sa capacité à être conscient de son environnement radioélectrique. En effet, afin d'optimiser au maximum les opportunités spectrales qui lui sont offerts, le dispositif radio intelligent doit être capable de transmettresur des bandes laissées libres tout en réalisant un sondage spectral afin de ne pas interférer avec les utilisateurs ayant la priorité sur la bande mais aussi pour détecter d'autres fréquences vacantes. Dans le cadre de cette thèse, nous proposons de nous concentrer sur la problématique de détection de spectre dans un environnement à très forte mobilité. Certaines contraintes sont à prendre en compte, telles que la vitesse. À cela s'ajoute les contraintes de réglementation concernant les critères de détection, telles que la norme IEEE 802.22 WRAN qui stipule que la détection d'un utilisateur prioritaire doit être réalisée à -21dB dans un laps de temps de 2 secondes. L'objectif est donc de concevoir un terminal radio intelligent dans les conditions physiques et réglementaires de transmission dans un environnent ferroviaireThe main objectives of railway operators are to increase safety, reduce operating and maintenance costs, increase attractiveness and profit by offering new services to customers. These objectives will be achieved through a huge increase of data fluxes between existing infrastructure and the technologies currently used on the train. Spectral efficiency, optimization of radio resources, interoperability and reliability of communications are major elements for railway applications. These constraints and the sporadic use of available frequency bands have gave rise to cognitive radio. Cognitive radio is an emerging technology that improves the performance of existing radio systems by integrating artificial intelligence with software radio. A cognitive radio system is defined by its ability to be aware of its radio environment. Indeed, to optimize as much as possible the available spectral opportunities, the cognitive radio device must be able to transmit on free bands while performing a spectrum sensing to not interfere with users having priority on the band and to detect other vacant frequencies. As part of this thesis, we propose to focus on the problem of spectrum detection in a highly mobile environment. Some constraints should be considered, such as speed. Added to this, there are regulatory constraints on detection criteria, such as the IEEE 802.22 WRAN standard, which stipulates that detection of a priority user must be performed at -21 dB within a period of 2 seconds. The objective is therefore to design an intelligent radio terminal in the physical and regulatory conditions of transmission in a railway environment