Dissertations / Theses on the topic 'Cognition – Physiology'
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Wesso, Iona. "Science text: Facilitating access to physiology through cognition-based reading intervention." University of the Western Cape, 1995. http://hdl.handle.net/11394/8485.
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Philosophiae Doctor - PhDReading and understanding science text is the principal means by which students at tertiary level access scientific information and attain scientific literacy. However, understanding and learning from science texts require cognitive processing abilities which students mayor may not have. If students fail to understand scientific text, their acquisition of subject knowledge and expertise will be impeded and they will fail to develop into thinking and independent learners, so crucial for academic progress and achievement. A major assumption in this study is thus that in order to increase access to science subjects there is a need to explicitly teach the thinking abilities involved in learning science from text. A review of the literature showed that while reading to learn from scientific text poses special challenges to students faced with this unfamiliar genre, little is known about reading (and thinking) for science learning. A synthesis of current research which describes the neglected interface between science learning, science reading and cognition is given in the literature review of this study. This synthesis highlights, in particular, the parallel developments in research into science learning and reading; the lack of integration of research in these areas; the absence of investigations on science reading located within the cognitive domain; and the absence of research into reading as it affects cognition and cognition as it affects reading in subject-specific areas such as physiology Possibilities for improving students' cognitive performance in reading to learn through intervention were considered from a cognitive perspective. From this perspective, students' observable intellectual performance can be attributed to their underlying knowledge, behaviour, and thought processes. Accordingly, the mental processes involved in comprehending scientific concepts from text and the cognitive processes which the students bring to the learning situation become highly relevant to efforts to improve cognitive skills for learning science Key questions which were identified to serve as a basis for intervention included: a) What cognitive abilities are needed for competent reading comprehension as demanded by physiology text?; b) How adequate is the cognitive repertoire of students in dealing with physiology text? With regard to these questions a catalogue of cognitive functions as formulated by Feuerstein et al (1980) was identified as optimally suited for establishing the cognitive match between reading tasks and students. Micro-analyses of the cognitive demands of students' textbook material and the cognitive make-up of second-year university students revealed a profound mismatch between students and their learning material. Students lacked both comprehension fostering and comprehension monitoring abilities appropriate to the demands of the learning task. The explication of the cognitive requirements which physiology text demands served as a basis for systematically designing instruction whereby appropriate intellectual performance for scientific comprehension from text may be attained Subsequent intervention was based on the explicit teaching of thinking abilities within the context of domain-specific (physiology) knowledge. An instructional framework was developed that integrated cognitive learning theories and instructional prescriptions to achieve an effective learning environment and improve students' cognitive abilities to employ and extend their knowledge. The objective was that the instructional model and resultant instructional methods would ensure that students learn not only the desired kinds of knowledge by conceptual change, but also the thought processes embedded and required by reading scientific material for appropriate conceptual change to take place. Micro-analysis of the cognitive processes intrinsic to understanding physiology text illuminated cognitive demands such as, for example, the ability to: transform linearly presented material into structural patterns which illuminate physiological relationships; analyse conceptually dense text rich in "paradoxical jargon"; activate and retrieve extensive amounts of topic-specific and subject-specific prior knowledge; to visualise events; and contextualise concepts by establishing an application for it. Within the above instructional setting, the study shows that the notion of explicitly teaching the cognitive processes intrinsic to physiology text is possible. By translating the cognitive processes into cognitive strategies such as assessing the situation, planning, processing, organisation, elaboration, monitoring and reflective responses, the heuristic approach effectively served to guide students through various phases of learning from text. Systematic and deliberate methods of thought that would enhance students problem-solving and thinking abilities were taught. One very successful strategy for learning from physiology text was the ability to reorganise the linearly presented information into a different text structure by means of the construction of graphic organisers. The latter allowed students to read systematically, establish relationships between concepts, identify important ideas, summarise passages, readily retrieve information from memory, go beyond the given textual information and very effectively monitor and evaluate their understanding In addition to teaching appropriate cognitive strategies as demanded by physiology text, this programme also facilitated an awareness of expository text conventions, the nature of physiological understanding, the value of active strategic involvement in constructing knowledge and the value of metacognitive awareness. Also, since the intervention was executed within the context of physiology content, the acquisition of content-specific information took place quite readily. This overcame the problem of transfer, so often experienced with "content-free" programmes. In conclusion, this study makes specific recommendations to improve science education. Inparticular, the notion of teaching the appropriate cognitive behaviour and thought processes as demanded by academic tasks such as reading to learn physiology seems to be a particularly fruitful area into which science educational research should develop and be encouraged.
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Wiet, Ryan. "The effects of acute aerobic exercise on BDNF levels and cognition in postmenopausal women." Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1527873335485353.
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Andrillon, Thomas. "The sleeping brain at work : perceptual processing and learning in human sleep Thomas Andrillon." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEE004/document.
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Tous les soirs, nous nous endormons; tous les matins, nous nous réveillons. De ce qui advient entre temps nous gardons peu de souvenirs. Les personnes qui nous entourent pourraient nous dire que nous avons bougé, parlé, ri ou crié, que les émotions les plus vives ont pris le contrôle de notre corps sans pour autant avoir laissé le moindre souvenir. Ou encore, les personnes qui nous entourent ont pu bouger, parler, rire ou crier sans que nous nous en rendîmes compte le moins du monde. Ou au contraire, nous pouvons émerger de la plus fantastique des aventures dans un lit pourtant bien calme,bercé par le calme tic-tac de l’horloge. Il semble que le sommeil opère une dissociation complète entre ce qui arrive dans notre environnement immédiat et dans notre esprit,sans pour autant que la chose éveille en nous la moindre alarme. À tout moment qui plus est, nous pouvons nous réveiller et reprendre conscience de notre environnement de façon quasi instantanée. Curieusement, il semble que certains sons aient une plus grande facilité à nous réveiller que d’autres. Sommes-nous donc complètement déconnectés de notre environnement quand nous dormons ?Every night we fall asleep and every morning we wake up. From what happens in the meantime, little is remembered. Others may say that we have moved, talked, laughed orcried, that the strongest and most vivid emotions took control of our body without leaving the faintest memory behind. Or others may have moved, talked, laughed or cried without our slightest notice. On the contrary, we can emerge from the most fantastic adventure in a quiet bed, cradled by a peaceable ticking clock. Without causing us much alarm, it seems that sleep entails a dissociation between what happens in ourenvironment and within our mind. Yet, at any moment, we can wake up and immediately regain consciousness of the surrounding world. Interestingly, it seems that certain sounds are more likely to awake us than others.Thus, are we completely disconnected from our environment when we sleep?
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Cattelain, Thibault. "Production des consonnes plosives du français : du contrôle des bruits de plosion." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAS011/document.
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L’étude de la production des consonnes occlusives (/p/, /b/, etc) a un intérêtparticulier pour la compréhension du contrôle moteur de la production de la parole. Eneffet, la production de ces consonnes requiert une coordination fine des 3 niveaux deproduction : respiration, vibration des cordes vocales, articulation.L’objectif de mes travaux de thèse est d’étudier la coordination des gestesrespiratoires, laryngés et articulatoires permettant de contrôler la variation de certains traits acoustiques des consonnes occlusives, plus spécifiquement les caractéristiques acoustiques de leurs bruits de plosion (intensité, durée, spectre, cruciaux pour l’intelligibilité des consonnes occlusives). Une partie importante de mes travaux de thèse s’intéresse également au contrôle musculaire de cette coordination gestuelle.Ces objectifs demandent un travail méthodologique préliminaire pour comparer,développer et implémenter différentes techniques de mesure et d’estimation des effortsarticulatoires de production de parole, à différents points de vue, physiologiques etmécaniques (cinématique du mouvement labial, capteurs de force, électromyographieorofaciale). L’exploration de ces questions a donné lieu à l’acquisition d’une large base de données (acoustiques et physiologiques) de production de consonnes occlusives du français chez une vingtaine de locuteurs adultes sains, incluant 2 modes de phonation (modal et chuchoté), 2 débits de parole (normal et rapide) et plusieurs niveaux d’effort articulatoire.L’analyse de cette base de données a permis de confirmer certaines relations déjà établies en parole conversationnelle entre l’intensité acoustique du bruit de plosion et le maximum de Pression Intra-Orale (ou la vitesse d’ouverture des lèvres pour les consonnes labiales), et entre les paramètres spectraux du bruit de plosion (skewness et kurtosis) et les paramètres articulatoires de déplacement de la langue pour les consonnes alvéolaires et vélaires.D’autres relations (non décrites dans la littérature) ont été observées en paroleconversationnelle : 1- l’intensité acoustique du bruit de plosion augmente lorsque le degré de compression labial et la vitesse de fermeture des lèvres augmentent pour les consonnes labiales ; 2- l’intensité acoustique du bruit de plosion augmente lorsque la vitesse tangentielle du mouvement d’élévation de la langue augmente pour les consonnespalatales ; 3- le degré de compression labial, les vitesses de fermeture et d’ouverture des lèvres augmentent significativement lorsque les activités des muscles Orbicularis Oris Supérieur (OOS) et Dépresseur de la Lèvre Inférieure (DLI) augmentent (dans les phases du mouvement où ils sont agonistes). Ces relations évoluent en fonction du mode de phonation (l’accent est mis en qualité chuchotée sur l’utilisation de paramètres cinématiques au détriment des paramètres aérodynamiques, articulatoires et temporels) et du débit de parole (la plupart des paramètres physiologiques et articulatoires perdent avec le débit leur efficacité de contrôle des caractéristiques acoustiques)Stop consonants (/p/, /b/, etc) are of particular interest for the understanding of speech motor control. Indeed, the production of these stop consonant requires the coordination of the 3 production levels: breathing, vocal folds vibration and articulation.The main goal of my thesis is to study how respiratory, laryngeal and articulatory gestures coordinate to control the variation of acoustic features of stop consonants, especially of their burts (intensity, duration, spectrum), which are crucial for stop consonant intelligibility. An important part of my thesis work also focuses on the muscular control of lip gestures in the production of bilabial stops. These goals needed a preliminary methodological work to compare, develop and implement different techniques, in order to measure and estimate articulatory efforts of speech production, physiologically and mechanically (lip movement kinematics, force sensors, orofacial electromyography). This methodological exploration has given rise to theacquisition of a large database (acoustic and physiological data) of French stop consonant productions, for twenty healthy speakers, including 2 phonation modes (modal and whispered), 2 speech rates (normal and fast) and several levels of articulatory effort.The analysis of this database has confirmed relationships already established inconversational speech between burst intensity and the maximum of intra-oral pressure (or opening velocity of lips for labial stops), and between spectral features of the burst and articulatory parameters of tongue movements for alveolar and velar stops. New other relationships have been observed in conversational : 1- the burst acoustic intensity increase when the lips compression and opening velocity increase (for labial stop consonants) ; 2-the burst acoustic intensity increase when the elevation tangential velocity of the tongue increase (for palatal stop consonants) ; 3- the lips compression, lips opening and closing velocities significantly increase when the activities of the OOS (Superior Orbicularis Oris) and DLI (Depressor of the Inferior Lip) muscles increase (during the movement phasis where muscles are agonists). These relationships depend on phonation quality (in whispered speech the accent is made on using kinematic parameters at the cost of aerodynamic, articulatory and temporal ones) and speech rate (most of physiological and articulatory parameters lost efficacies for acoustic control when speech rate increase)
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Broughan, Christine. "The effects of the olfactory properties of essential oils on selected aspects of cognition." Thesis, Coventry University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365208.
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Ross, Amy Patricia. "Effects of a High Fructose Diet on Physiology and Cognition in Male Sprague-Dawley Rats." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/psych_theses/45.
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Fructose consumption has increased exponentially during the past four decades. The physiological effects of a high fructose diet include obesity and insulin resistance. In animal models, the effects of a high fructose diet on fat distribution are inconclusive in that some studies find increases in body mass and lipids while others find no effect. Recent findings indicate that a high fructose diet causes hippocampal insulin resistance in hamsters, raising the possibility that the diet causes impairments in cognition. The following experiments tested the hypotheses that a high fructose diet alters fat distribution rather than total body mass and impairs hippocampal-dependent memory. Results indicated that the high fructose diet did not affect fat distribution, but did increase plasma triacylglycerides. Interestingly, the diet also impaired spatial reference memory in the Morris water maze, and this effect was correlated with plasma triacylglycerides. These results indicate that a high fructose diet impairs brain function.
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Tsang, Yuen. "The relationship between balance and functional outcomes of subacute in-patient rehabilitation in stroke patients." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B3197224X.
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Sleik, Ryan John, and University of Lethbridge Faculty of Arts and Science. "Does postural threat alter the role of cognition for postural control?" Thesis, Lethbridge : University of Lethbridge, University of Lethbridge. Faculty of Arts and Science, 2001, 2001. http://hdl.handle.net/10133/141.
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Cognitive demands for postural control in younger and older adults were examined under conditions of postural threat. Age-related differences emerged in the distribution of attention for postural control in conditions of postural threat. Specifically, porutral compensations were implented to reduce cognitive demands for postural control. In addition, it was determined that the effect of performing a secondary cognitive task on postural control was altered when the potential consequences of instability were increased. Younger adults were found to maintain postural control and improve secondary task performance in conditions of increased threat whereas postural control in older adults improved at the expense of secondary task performance. In older adults, postural control may be prioritized under conditions that increase arousal and the consequences of imbalance. These findings have implications for reducing falls in elderly populations, as they reveal that the ability to adequately perform concurrent tasks is compromised when environmental factors threaten balance in elderly populations.xi, 113 leaves ; 28 cm.
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Henderson, Nigel E. "What influences decisions students make in selecting texts to support learning in anatomy and physiology?" Thesis, Anglia Ruskin University, 2015. http://arro.anglia.ac.uk/582315/.
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The provision of key text reading lists relies on students to select one they will utilise in undertaking a course. In anatomy and physiology an array of texts exist providing lecturers with the task of deciding the most suitable for inclusion within this list, the final choice for a student to undertake. Little evidence was found to identify the decision-making a student undertook in selecting a text. Based on disparate theoretical concepts an initial development of a conceptual process framework followed to provide a basis from which to identify influences which impacted on the student decision-making process. Using a mixed methods design a survey of students (N=964) undertaking anatomy and physiology courses was conducted whose results, following analysis provided the focus for in depth interviews. These included students (n=15), lecturers (n=3) authors (n=5) and publishers (n=2). Thematic analysis of the transcripts identified four overarching themes these being the Perception of the Textbook, Choice of the Textbook, Mismatch of Perceived Needs and Place of the Textbook. The results suggested two main influences which impacted on the student when choosing a text, those of existing prior knowledge and recommendation. Without prior knowledge, comprehension and cognition of the text was difficult. Recommendation by a lecturer or reading list, a strong influence, saw students selecting a recommended text without considering their own needs leading to an inability to use this. Without knowledge and recommendation students utilised aesthetic preference and heuristics in selecting a text, with many selecting additional texts to assist in using recommended texts. The results led to the development of the conceptual process framework indicating choice was a complex process for the student. Selecting a text is complex and affected by numerous influences. The study highlights a process through which a student traverses as they undertake the selection of their text. The study conclusions have led to the development of the Process Framework for Text Selection providing a novel and coherent linking of established theoretical concepts.
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Aaron, Elizabeth Mae. "Maternal and Child Characteristics Predicting Protective Parenting: Cognition as a Mechanism." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1624378278091593.
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Valiante, A. Grace (Antonella Grace). "Acute effects of feeding on cognition in healthy well-nourished newborn infants." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115845.
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Despite considerable evidence in older populations that food intake can improve mental performance, little is known about the acute effects of feeding on cognition in the newborn period, a time when learning and memory are critical for discovering and adapting to everyday experiences. Feeding occurs well over 2500 times in the first year of life, raising the possibility that iterative effects on cognition may have cumulative effects over time. We recently demonstrated feeding enhancement of memory in two-to-three day old infants. Infants tested after a feed (versus before) displayed better memory for unfamiliar spoken words they previously habituated to and that were represented after a 100s delay. In this Doctoral Thesis, Studies 1 and 2 explore further the influence of feeding on short-term retention of spoken words. Memory was assessed using headturning and the Habituation-Recovery response. Study 1 extended the effect to older infants aged two-to-three weeks. Memory was enhanced after a feed over even longer delays, including 100s, 200s, 300s, 400s, and 500s. The overall gain in memory as measured by prefeed and postfeed differences at each delay was over two minutes long. Because newborn infants are more likely to hear recurrent words spoken by familiar voices, auditory experiences that they preferentially recognize, Study 2 looked at the separate effects of familiarity and feeding. Two day-old infants were assessed for either familiar speech-sound ("baby" spoken by the mother) or unfamiliar speech-sound from Study 1 ("beagle" spoken by a female stranger). The baby-mother sound stimulus was remembered better over a retention interval of 85 seconds than unfamiliar beagle-stranger, suggesting a strong influence of familiarity. To define the extent of the feeding effect, Study 3 examined sensorimotor processing of a reflex response. Three day-olds were assessed on habituation and retention of habituation of the glabella blink reflex over delays of 8s and l8s. No effect of feeding was found. Taken together, the implications of these findings are twofold. First, enhancement of memory for speech-sound by iterative feeding or recurrent exposure to familiar speech-sound stimuli may facilitate the acquisition of language. Second, feeding effects on cognition may depend on the nature of the task and previous experience with the stimulus. Further research is necessary for identifying what kinds of information and what processing abilities are more susceptible to the effects of feeding in early infancy.
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Hällgren, Mathias. "Hearing and cognition in speech comprehension. Methods and applications." Doctoral thesis, Linköpings universitet, Teknisk audiologi, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5039.
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Central auditory processing is complex and can not be evaluated by a single method. This thesis focuses on assessment of some aspects of central auditory functions by the use of dichotic speech tests and cognitive tests that tax functions important for speech processing. Paper A deals with the cognitive effects in dichotic speech testing in elderly hearing-impaired subjects. It was found that different listening tasks in the dichotic tests put different demands on cognitive ability, shown by a varying degree of correlation between cognitive functions and dichotic test parameters. Age-related cognitive decline was strongly connected with problems to perceive stimuli presented to the left ear. Paper B presents a new cognitive test battery sensitive for functions important for speech processing and understanding, performed in text, auditory and audiovisual modalities. The test battery was evaluated in four groups, differing in age and hearing status, and has proven to be useful in assessing the relative contribution of different input-modalities and the effect of age, hearingimpairment and visual contribution on functions important for speech processing. In Paper C the test battery developed in Paper B was used to study listening situations with different kinds of background noise. Interfering noise at +10 dB signal-to-noise ratio has significant negative effects on performance in speech processing tasks and on the effort perceived. Hearing-impaired subjects showed poorer results in noise with temporal variations, and elderly subjects were more distracted by noise with temporal variations, especially by noise with meaningful content. In noise, all subjects, particularly those with impaired hearing, were more dependent upon visual cues than in the quiet condition. Hearing aid benefit in speech processing with and without background noise was studied in Paper D. The test battery developed in Paper B was used together with a standard measure of speech recognition. With hearing aids, speech recognition was improved in the background condition without noise and in the background condition of ordinary speech. Significantly less effort was perceived in the cognitive tests when hearing aids were used, although only minor benefits of hearing aid amplification were seen. This underlines the importance of considering perceived effort as a dimension when evaluating hearing aid benefit, in further research as well as in clinical practice. The results from the studies contribute to the knowledge about speech processing but also to the search for more specific evaluation of speech understanding, incorporating both sensory and cognitive factors.The ISBN 91-85297-49-6 in the printed verison is incorrect. The correct ISBN is 91-85297-93-3.
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Majdi, Maryam. "Brain ageing : cognitive status and cortical synapses." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115704.
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This thesis focused on the spatiotemporal patterning of classical excitatory and inhibitory synaptic contacts accounting for the majority of cerebral cortical connections, in relation to ageing and cognitive status. These investigations tested the hypothesis that higher CNS functions depend on the balance between excitatory and inhibitory synaptic connections. Glutamatergic and GABAergic presynaptic bouton densities were determined in aged animals segregated according to their cognitive status into aged and cognitively unimpaired (AU) and aged and cognitively impaired (AI), using the Morris water maze. These two groups were compared in terms of behaviour and the pattern of excitatory and inhibitory synapses. It was evident that an excitatory and inhibitory presynaptic decline is associated with age-related cognitive impairments; whereby both glutamatergic and GABAergic boutons gradually diminish from young to AU to AI. Nevertheless, the balance between excitatory and inhibitory presynaptic inputs was maintained. To determine whether postsynaptic sites differed with respect to ageing and cognitive impairments, excitatory and inhibitory postsynaptic scaffold proteins were investigated in the same cohort of segregated aged animals. There was an imbalance in density ratio between immunoreactive sites of excitatory versus inhibitory postsynaptic scaffold proteins in AI animals. This resulted from a marked decrease in the density of excitatory postsynaptic sites. To further investigate ultrastructural aspects of excitatory synapses I carried out electron microscopical studies of cerebral cortex to measure the abundance of NR2 receptor subunits of the NMDA receptor- a receptor site directly associated with excitatory postsynaptic scaffold proteins. This study revealed that NR2 immunoreactive sites were largely preserved during age-related cognitive decline with an uneven profile distribution. Finally, protein expression of specific receptor subunits and key proteins representative of excitatory and inhibitory postsynaptic sites was investigated by semi-quantitative Western blot analyses in selected cortical areas. It was clear that many of these postsynaptic proteins are affected by age and cognitive status. The most striking change was a marked up-regulation in neuroligin-1 in AI animals, which may affect the delicate balance between excitatory versus inhibitory synaptic inputs. Another notable finding was the down-regulated expression of GluR2 receptor subunits in AI animals, which should have implications for neuronal Ca2+ regulation. In conclusion, we have demonstrated the greater vulnerability of excitatory postsynaptic sites in aged and cognitively impaired animals.
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Jurdak, Nicole Ann. "The Effects of Diet Induced Obesity and Metabolic Irregularities on Hippocampal-Based Cognition and Neuroplasticity in Young Female and Male Rat." Thesis, Tufts University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10255460.
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Recent research has associated obesity with cognitive impairments and alterations in brain-derived neurotrophic factor (BDNF), with the majority of studies examining this in older adult or aging animals. To expand upon these efforts, two experiments were performed to examine the effects of diet-induced obesity (DIO) on spatial performance and hippocampal BDNF expression in young adult female and male rats. To expand upon these efforts, we examined these effects over dietary interventions of differing durations. To investigate these issues rats (female rats in Experiment 1 and male rats in Experiment 2) were assigned to either a standard chow condition or a DIO condition and remained on these diets for 4-, 8- or 12-weeks. Compared to their chow-fed counterparts, female DIO rats consumed significantly more average weekly calories, weighed significantly more, and exhibited significant alterations in glucose metabolism. However, these obesity-related physiological changes were not associated with concurrent impairments in spatial ability as measured using the Morris water maze, and only the 4-week DIO dietary intervention demonstrated a difference in hippocampal BDNF mRNA expression. Compared to their chow-fed counterparts, male DIO rats consumed significantly more average weekly calories than their chow-fed counterparts, weighed significantly more, and exhibited significant alterations in glucose metabolism. However, obesity-related physiological alterations were not associated with concurrent impairments in spatial ability or differences in BDNF mRNA expression, with the exception of the 12-week DIO animals performing significantly better than their chow-fed counterparts during the reversal probe trial on the final day of training. These findings were unexpected and will be discussed further later in the thesis.
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Le, Gal Patricia Margaret. "Cognitive aspects of emotional expression processing." Thesis, University of Stirling, 1999. http://hdl.handle.net/1893/1772.
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This thesis investigates the hypothesis that emotions play an influential role in cognition. Interference between facial emotional expression processing and selected tasks is measured using a variety of experimental methods. Prior to the main experimental chapters, the collection and assessment (Chapter 2, Exp. 1) of stimulus materials is described. Experiments 2-11 then concentrate on the likelihood of interference with other types of information from the face. Findings using a Garner design suggest that, although identity processing may be independent of expression variation, expression processing may be influenced by variation in identity (Exps. 2-4). Continued use of this design with sex (Exps. 6-7) and gaze direction (Exps. 9-10) information appears to support the (mutual) independence of these facial dimensions from expression. This is, however, in contrast to studies that indicate the modification of masculinity judgements by expression (Exp. 5), and the interaction of gaze direction and expression when participants rate how interesting they find a face (Exp. 8). Further to this, a search task (Exp. 11) shows that slower responses to an angry (cf. happy) face looking at us, may be due to the presence of an aversive mouth. Experiments 12-15 test for interference in the field of time perception: complex interactions between expression and encoder and decoder sex are indicated. Finally, Experiments 16-17 find that exposure to a sequence in which the majority of faces are angry depresses probability learning, and that prior exposure to varying quantities of angry and happy faces affects our later memory for them. Overall, there is evidence that exposure to emotional expressions may affect other (selected)c ognitive processesd ependingu pon which expressionsa re used and which experimental methods are chosen. It is suggested that future investigations would benefit from techniques that describe the temporal profile of an emotional response.
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Bohara, Gyanendra. "Application of Statistical Physics in Human Physiology: Heart-Brain Dynamics." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248449/.
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This dissertation is devoted to study of complex systems in human physiology particularly heartbeats and brain dynamics. We have studied the dynamics of heartbeats that has been a subject of investigation of two independent groups. The first group emphasized the multifractal nature of the heartbeat dynamics of healthy subjects, whereas the second group had established a close connection between healthy subjects and the occurrence of crucial events. We have analyzed the same set of data and established that in fact the heartbeats are characterized by the occurrence of crucial and Poisson events. An increase in the percentage of crucial events makes the multifractal spectrum broader, thereby bridging the results of the former group with the results of the latter group. The crucial events are characterized by a power index that signals the occurrence of 1/f noise for complex systems in the best physiological condition.
These results led us to focus our analysis on the statistical properties of crucial events. We have adopted the same statistical analysis to study the statistical properties of the heartbeat dynamics of subjects practicing meditation. The heartbeats of people doing meditation are known to produce coherent fluctuations. In addition to this effect, we made the surprising discovery that meditation makes the heartbeat depart from the ideal condition of 1/f noise.
We also discussed how to combine the wave-like nature of the dynamics of the brain with the existence of crucial events that are responsible for the 1/f noise. We showed that the anomalous scaling generated by the crucial events could be established by means of a direct analysis of raw data. The efficiency of the direct analysis procedure is made possible by the fact that periodicity and crucial events is the product of a spontaneous process of self-organization. We argue that the results of this study can be used to shed light into the nature of this process of self-organization.
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Tsang, Yuen, and 曾苑. "The relationship between balance and functional outcomes of subacute in-patient rehabilitation in stroke patients." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B3197224X.
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Young, Paul. "An exploration of the impact of self-contained breathing apparatus tasks upon the cognition, physiology, and coping strategies of English firefighters during structural fires." Thesis, Northumbria University, 2012. http://nrl.northumbria.ac.uk/11366/.
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Firefighting operations are characterised by high time pressures, a high degree of task and environment uncertainty, life-or-death situations, and the continuous emergence of novel events. Despite this, the factors considered most demanding to firefighters and the strategies that lead to effective management of physiological and psychological stressors at the fire scene are yet to be fully understood. To address this issue, study 1 utilised a qualitative approach employing a series of focus groups and individual interviews to establish the operational tasks considered to be most demanding by firefighters. Results showed that stressors could be classified into five higher order categories dominated by the physical demands of wearing self-contained breathing apparatus (SCBA) and firefighting activities. Coping responses were grouped by problem-focused and emotion-focused techniques (Lazarus and Folkman, 1984), and also considered coping strategies at early, mid and late career stages. Study 2 utilised a longitudinal approach to examine the development of SCBA specific coping strategies with trainee firefighters over a 12-month period. Stressors were characterised by five higher-order stressors present throughout, and the firefighters reported high levels of control over the task and satisfaction with their performance despite task severity. Study 3 consisted of data collection undertaken during a series of commonly encountered SCBA tasks, including a comparison of novice and experienced firefighters during a single live firefighting task, and experienced firefighters undertaking a series of frequently encountered SCBA tasks. Results found that there were significant changes in cardiovascular and psychological responses of both novice and experienced firefighters following a live firefighting task. There was also a series of significant responses in experienced personnel completing concurrent guideline, search and rescue, and live firefighting tasks. The final study (study 4) considered the demands of SCBA from a command and control perspective. Incorporating a purpose-built incident command suite, the task was found to require high levels of mental and temporal demand but minimal levels of physical demand or frustration. Of the four roles examined, the incident commanders displayed highest levels of task demands, stress, and state anxiety. The programme of work in this thesis highlights the complex environments firefighters face, the importance of on-scene coping techniques, and the methodological difficulties involved when attempting to capture and analyse data within this population.
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Nuckols, Virginia R. "Cognitive and vascular function in women with a history of preeclampsia." Thesis, University of Iowa, 2019. https://ir.uiowa.edu/etd/6822.
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Background: Women are more likely to develop age-related cognitive impairment compared with men of the same age. Pregnancy complications, such as preeclampsia (PE), and menopause may contribute to an elevated risk of cognitive decline with aging in women potentially through an adverse impact on vascular function. PE is associated with a heightened risk of hypertension and large elastic artery stiffness (i.e., aortic and carotid arteries) for several years postpartum. Persistent large artery stiffness may be further amplified in women with a history of PE during the menopause transition, which is marked by an accelerated rate of vascular aging. However, large artery stiffness has not been studied extensively in postmenopausal women with a history of PE. Age-related elevations in large artery stiffness are associated with cognitive decline in middle-aged and older adults however, this relation has not been investigated in young women with a history of PE. Moreover, the degree to which elevated large artery stiffness is amplified and associated with reduced cognitive function among postmenopausal women with a history of PE remains unknown. The purpose of this study was to examine the extent to which large elastic artery stiffness is associated with reductions in cognitive function in premenopausal and postmenopausal women with a history of PE.
Methods: Large elastic artery stiffness and domains of cognitive function were assessed in young women one year postpartum (n=18, ages 24-41 yrs.) and postmenopausal women (n=19, ages 52-77 yrs.) thirty-five years postpartum. Aortic stiffness was measured via non-invasive applanation tonometry at the carotid and femoral pulse sites and expressed as carotid-femoral pulse wave velocity (cfPWV). Carotid artery stiffness was quantified as beta-stiffness index (β-stiffness) was measured via ultrasonography and carotid tonometry. Cognitive tests were administered to assess cognitive function in immediate and delayed recall, working memory, processing speed, and executive function.
Results: Premenopausal women with a history of PE had higher systolic blood pressure (121 ± 4 vs. 101 ± 3 mmHg, p =0.01) one year postpartum but did not differ significantly from controls in cfPWV (6.2 ± 0.4 vs. 5.1 ± 0.2 m/s, p =0.08), β-stiffness (6.1 ± 0.5 vs. 6.1 ± 0.7 U, p =0.97), or cognitive domains of memory, executive function, or processing speed (all p>0.05). Higher systolic blood pressure was associated with lower executive function (r = -0.53, p = 0.05) in young women one year postpartum. Postmenopausal women with a history of PE did not differ from controls in blood pressure, large artery stiffness, or age-adjusted cognitive domains of memory, executive function, or processing speed (all p>0.05). Large artery stiffness was not associated with cognitive function in premenopausal or postmenopausal women.
Conclusions: Young women with a history of PE had elevated systolic pressure one year postpartum, which was associated with reductions in executive function. Large artery stiffness was not elevated or related to cognitive function in postmenopausal women with a history of PE. These preliminary findings suggest that young women with a history of PE are susceptible to reductions in selective cognitive domains related to higher blood pressure, but this effect does not appear to extend into the postmenopausal period.
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Pal, Amrita. "Identification of the Neurobiological Basis of Hemodynamic Responses Correlated with Cognitive Stroop Task Performance After an Acute Bout of Aerobic Exercise." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157584/.
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Cardiovascular activities may increase the brain blood flow improving neuronal activities leading to improved cognition. Consequently, the effects of an acute bout of moderate intensity aerobic exercise on brain hemodynamics and its correlation with cognitive color-word Stroop task performance were tested. The Stroop tasks were congruent (color matches word) and incongruent (color does not match word). Prefrontal (PFC) and motor cortex (MC) blood flow was recorded by fNIRS (functional near-infrared spectroscopy) while the subject was performing the Stroop tasks before and after the 30 minutes of exercise or equivalent time of rest controls (checking for practice effects). Ninety human subjects of age 24± 6, 20 ADHD (attention-deficit hyper-activity disorder), 27 High-BMI (>25), 29 males were recruited. Reaction time ‘RT' decreased (p<0.05) after exercise for both the congruent (12%) and incongruent (10%) Stroop tasks, compared to 8% with practice alone. Accuracy did not change after practice or exercise. HR changes after exercise correlated (p<0.05) with better accuracy and faster RT for the incongruent Stroop task. In general, a metabolic lag occurred in the neuronal deoxy- hemoglobin (Hb) signals behind the systemic oxy-Hb signals. PFC showed the highest effect sizes of Stroop task-responsive systemic hemodynamic changes compared to baseline irrespective of rest or exercise. Yet, PFC showed most significant (p<0.001) neuronal hemodynamic changes between the before and after exercise sessions, and these changes were opposite for right and left PFC, and opposite for congruent and incongruent Stroop tasks. Correlating the RT and mistakes with hemodynamics for both the Stroop tasks revealed that, after exercise, neuronal hemodynamic changes occurred at both PFC and MC associated with faster RT (p<0.05), and systemic hemodynamic responses occurred at PFC correlated (p<0.05) with mistakes. Overall, it was concluded that exercise changed the neuronal hemodynamic changes affecting speed; however, neuronal metabolic changes did not occur sufficiently to help improve accuracy in all subjects.
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Simpson, Johanna. "The genetics of affective cognition : electrophysiological evidence for individual differences in affective picture processing, attention and memory." Thesis, University of Stirling, 2016. http://hdl.handle.net/1893/25203.
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Affect and cognition have traditionally been considered mutually exclusive domains and their study has evolved into two separate research fields. In recent years, however, there is increasing evidence of affective modulations of cognitive processes and interest in the study of affective cognition has grown. This thesis presents analyses of data collected in four mixed-design experiments between 2009 and 2011, which were designed to investigate affective memory and its electrophysiological correlates, individual differences in said affective memory and electrophysiological correlates, the time-course of affective memory and attentional disengagement from affective stimuli respectively. The first aim of the research presented here was to further understanding of how affective content influences picture processing and memory. Event-related potentials (ERPs) provide a valuable tool for the investigation of modulations of cognitive processes, as their excellent temporal resolution allows for the dissociation between different processes contributing to behavioural outcomes. Several important results for the study of affective cognition are reported: The late positive potential (LPP) was shown to be modulated differentially by affective content when compared to a behavioural attentional disengagement task. While the behavioural measure of attention replicated findings from participants’ self-report of arousal, LPP enhancement did not. This novel finding demonstrates that the affective modulation of the LPP cannot be used as an electrophysiological marker of slowed attentional disengagement as is common in the literature. In the domain of recognition memory, affective modulation of performance was shown to be time-sensitive, with effects developing faster for negative than for positive picture content. Affective pictures were associated with a less conservative response bias than neutral pictures but only negative pictures elicited better discrimination performance, driven by an increased in the rate of “remembered” as compared to merely familiar pictures. This was reflected in an increase of the ERP old/new effect for negative pictures in the 500 to 800ms time window, the purported correlate of recollection. The late right-frontal old/new effect between 800 and 1500 ms post stimulus onset was shown to be attenuated by affective content, supporting the interpretation of the late right-frontal effect as a correlate of relevance detection over a retrieval success interpretation. In combination, the findings add weight to the conclusion that affective content enhances memory through selective memory sparing for affective stimuli. Novel evidence for gender differences in affective cognition was found. Comparisons between female and male participants revealed that the affective modulation of the late right-frontal effect differs between the genders, underlining the importance of assessing and understanding gender differences as part of the study of affective cognition. Brain-derived neurotrophic factor (BDNF) gene val66met single nucleotide polymorphism (SNP), a small genetic change that affects the functioning of BDNF, a protein that plays an important role in neuron growth, differentiation and survival, is shown here to also affect the interaction of affect and cognition. BDNF val66met genotype modulated the early “familiarity” old/new effect selectively in response to positive pictures. The present study clearly demonstrates the value of the ERP technique in the investigation of individual differences in affective and cognitive processing and the need to take such individual differences into account as part of the endeavour to fully understand the mechanisms of affective processing, cognition and affective cognition. A better understanding of the role of gender and genetic differences in the affective modulation of affective processing and memory will have important practical implications in fields where affect and cognition interact.
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DuBose, Lyndsey Elisabeth. "Role of aging and aerobic fitness on large elastic artery stiffness, brain structure and cognitive performance in humans." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1590.
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Older age is a primary risk factor for the development of cardiovascular disease in part through the stiffening of the large cardiothoracic elastic arteries (e.g., aorta, carotid arteries). Aging is also associated with reduced cognitive function, cerebrovascular reactivity and brain white matter integrity, but whether these changes in brain structure and function are associated with age-related large artery stiffness remains unclear. In contrast, older adults who have high aerobic fitness demonstrate attenuated large artery stiffness and better cognitive performance compared to their sedentary counterparts, but the effects of aerobic fitness on white matter integrity and cerebrovascular reactivity with aging are conflicting and limited. Moreover, whether high aerobic fitness-associated lower large artery stiffness in older adults is associated with, and perhaps mediates, the beneficial changes in cognitive function and white matter structure remains unknown. The purpose of this study was to investigate the extent to which high aerobic fitness is associated with preserved white matter structure, cerebrovascular reactivity, and cognitive performance in aged individuals, and if these changes in brain structure and function are associated with attenuated large artery stiffness. In young (n=19, 23.6 ± 2.5 years) and old (n=22, 64.4 ± 4.2 years) healthy adults, large elastic artery stiffness was measured by carotid-femoral pulse wave velocity (cfPWV, aortic stiffness) via non-invasive applanation tonometry of carotid and femoral pulse waveforms and carotid artery beta-stiffness index (β-stiffness index) and compliance using high-resolution ultrasound and carotid blood pressure via applanation tonometry. Aerobic fitness was measured as maximal exercise oxygen uptake (VO2max) using respiratory gas analysis on an upright cycle ergometer. Older subjects were stratified as high or low fit based on gender and age VO2max classification. Letter, pattern and N-Back cognitive tests were used to assess processing speed and working memory respectively. Fractional anisotropy (FA) from diffusion tensor images and Blood Oxygenation Level Dependent (BOLD) imaging was used to assess cerebrovascular reactivity (CVR) response to a breath hold and brain activation during a working memory task. The association between large artery stiffness and FA was then assessed using a voxel-wise general linear model approach and a region-of-interest analysis.
Our results confirmed age-related increases in cfPWV, carotid β-stiffness index and central (carotid) but not brachial systolic blood pressure, and expected reductions in carotid compliance, VO2max, working memory and processing speed, and in white matter integrity in select brain regions (bilateral cingulate, frontal, occipital, temporal). In contrast, we found no age-associated differences in CVR to breath hold stimulus or change in BOLD response to the N-Back. In our cohort of health adults, we found that the age-related changes in large artery stiffness were not attenuated by high compared with low VO2max. Among older adults, large elastic artery stiffness was not associated with regional white matter integrity or cerebrovascular reactivity in any regions-of-interest. Greater carotid artery compliance and lower β-stiffness index was associated with higher processing speed, while compliance was related to higher d'Prime scores and lower reaction time on the 2-Back task among the older adults. CVR to a breath hold stimulus was not related to any measure of cognitive performance. VO2max was not associated with any measures of vascular function, brain structure, function or cognition, indicating relations between large artery stiffness and cognition were independent of aerobic fitness capacity. Taken together, these data suggest that select measures of cognitive performance, but not white matter structure or CVR, may be susceptible to age-related changes in carotid stiffness/compliance and that are unaffected by aerobic fitness. More work is needed to understand the mechanisms by which age-related declines in carotid artery compliance and increased carotid stiffness are associated with reductions in cognitive function in older adults.
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Marcano-Reik, Amy Jo. "Sleep-related activity and recovery of function in the somatosensory cortex during early development." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/2743.
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The corpus callosum, the major interhemispheric fiber tract, mediates communication between homotopic regions within the primary somatosensory cortex (S1). Recently, in 1- to 6-day-old neonatal rats, brief bursts of high-frequency, oscillatory activity - called spindle-bursts (SBs) - were described in S1 following sensory feedback from endogenously generated sleep-related myoclonic twitch movements and exogenously generated peripheral stimulation. To determine whether interhemispheric communication via the corpus callosum modulates the expression of SBs during this early period of development and contributes to cortical organization and plasticity, we investigated the endogenous (spontaneous) expression and exogenous (evoked) activity of SBs in neonatal rats with intact or surgically severed callosal fibers (i.e., callosotomy; CCx). We used Ag/AgCl cortical surface electrodes in the S1-forelimb region of the cortex to measure neurophysiological and behavioral activity in both intact and CCx subjects across the sleep-wake cycle during the first two postnatal weeks of development.
Our results demonstrate, for the first time, that the corpus callosum modulates spontaneous and evoked activity between homotopic regions in S1 as early as 24-hours after birth. In addition, CCx disinhibits cortical activity, nearly doubling the rate of spontaneous SBs through, but not after, postnatal day 6 (P6). CCx also significantly and reliably disrupts the evoked response to peripheral stimulation of the forepaw. To examine the role of sleep-related twitches and their associated sensory feedback (SBs in S1) - modulated by the corpus callosum - in cortical development and plasticity, we performed CCx or sham surgeries at P1, P6, or P8, and tested subjects the day of surgery or over the ensuing week of recovery. Regardless of age, CCx immediately disrupted SBs evoked by forepaw stimulation. The P1 and P6 CCx groups exhibited full recovery after one week; in contrast, the P8 group did not exhibit recovery of function, thus indicating an abrupt decrease in cortical plasticity between P6 and P8. Together, these results provide the first evidence that sleep-related myoclonic twitches and the associated sensory feedback in S1 (SBs) contribute to cortical development, plasticity, and recovery of function after interhemispheric communication is disrupted by callosotomy. CCx-induced disinhibition of spontaneous SBs is a transient phenomenon whose disappearance coincides with the onset of increased intrinsic connectivity, establishment of excitatory-inhibitory balance, and diminished plasticity in S1. Our findings indicate that CCx-induced disinhibition of spontaneous twitch-related SBs and disruption of evoked response to peripheral stimulation serve as a bioassay of somatosensory cortical plasticity during the early postnatal period.
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Gerhart, Hayden D. "Acute Effects of Normobaric Hypoxia and Cold Water Hand Immersion on Thermoregulatory Response and Cognitive Function." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1477928489720937.
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Dickey, Jr G. W. "Mindfulness-based cognitive therapy as a complementary treatment for combat/operational stress and combat post-traumatic stress disorder." Quantico, VA : Marine Corps Command and Staff College, 2008. http://handle.dtic.mil/100.2/ADA490935.
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Hoon, A. C. "The effect of manipulating the expression of the NR2B subunit of the NMDA receptor on learning and memory." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:eae324a3-873f-4b50-9bcc-8c43b72866a3.
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Overexpression of the NR2B subunit of the NMDA receptor in the forebrain has been shown to improve learning and memory in mice (Tang et al 1999), which provides exciting implications for the enhancement of human cognition. However, it was first essential to establish replicability, and since the Tang et al (1999) study used only male mice we wished to investigate possible sex differences. On the hidden platform watermaze, we found a trend for male NR2BOE mice to learn the task more quickly than male wildtype mice (as observed by Tang et al. 1999), but the opposite trend in female mice; female NR2BOE mice were slower to reach the hidden platform than female wildtype mice. This pattern of results was also observed on the spatial reference Y memory task and open field task (for anxiety), although not on the spatial working memory T maze task (despite a sex difference). However, wildtype and NR2BOE mice performed at similar levels on the novel object recognition task, the spatial novelty preference task, visible platform watermaze and visual discrimination task. A battery of tests considering some species typical behaviours of mice demonstrated that wildtype and NR2BOE mice were comparable on tests of motor ability, strength, co-ordination, anxiety, burrowing and nesting. This suggests that our behavioural results are not due to a general impairment or enhancement of species typical behaviours. We considered the possibility that the difference between the results of Tang et al (1999) and those we observed may be caused by age differences; hence we attempted to replicate our results on the hidden platform watermaze, spatial reference Y maze and open field test in age matched mice. However, the second cohort of NR2BOE mice performed at similar levels to wildtype mice, and at significantly improved levels compared to the mice of the first cohort. We also considered the effects of knocking out the NR2B subunit on learning and memory, and NR1 subunit deletion within the hippocampus. On the spatial working memory T maze, these mouse strains performed similarly to their respective wildtype strains. Similarly, on a two beacon watermaze (with one indicating the platform position), mice lacking the NR2B subunit were able to locate the platform in a similar length of time. To ensure that the null results we had observed in the second cohort were not due to loss of the NR2B protein overexpression in the forebrain, we performed polymerase chain reactions (PCR), quantitative real-time PCR, and Western blots. We ascertained that the transgene was indeed present and that NR2B mRNA and protein levels were elevated in the hippocampi of the NR2BOE mice. In conclusion, it is unclear why the behaviours we observed in the NR2BOE mice are different to those published in the literature. It is possible that they may be due to differences in environmental enrichment, but the cause of the genotype by sex differences observed in the mice of cohort 1 is unclear. Nonetheless, we have advanced our knowledge of the effects of modifications in the levels of the NR2B subunit of the NMDA receptor on learning and behaviour.
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Landean, Megan N. "THE RELATIONSHIP BETWEEN VITAMIN D, BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) AND RISK FOR FALLS ON INDIVIDUALS WITH MULTIPLE SCLEROSIS." Cleveland State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=csu1511794427717765.
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Varga, Adrienn Gabriella. "The Neural Basis of Head Direction and Spatial Context in the Insect Central Complex." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1487249074487484.
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Bolton, Andrew D. (Andrew Donald). "Linking dopaminergic physiology to working memory related neural circuitry." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/95848.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, 2014.Cataloged from PDF version of thesis. Vita.
Includes bibliographical references (pages 123-143).
Working memory is the ability to hold information "online" over a delay in order to perform a task. This kind of memory is thought to be encoded in the brain by persistent neural activity that outlasts the presentation of a stimulus. Interestingly, patients with schizophrenia, a heritable neurological disorder, perform poorly in working memory tasks that require the retention of a target in space, indicating that persistent neural activity related to spatial locations may be impaired in the disease. At the biophysical level, NMDA receptors and dopamine receptors have been continually implicated in supporting persistent activity during spatial working memory. Perhaps relatedly, drugs that target the dopamine system are regularly used in the treatment of schizophrenia, and drugs that target NMDARs induce schizophrenia-like symptoms in healthy individuals. In this thesis, I seek to further examine the possible connection between NMDA receptors, the dopamine system, and schizophrenia-related working memory deficits. We find that homocysteine, a dopamine breakdown product that is upregulated in the blood of schizophrenia patients, strongly impacts NMDAR currents by reducing channel desensitization and altering peak amplitude. Additionally, we find that the dopamine system itself, which is traditionally studied in areas like striatum and prefrontal cortex, is organized in a behaviorally relevant pattern in the superior colliculus (SC), a brain region that shows persistent activity during spatial working memory tasks. The electrophysiological affects of dopamine on the SC suggest that dopamine dysregulation could have previously unexplored effects on spatial attention, sensorimotor integration, and working memory.
by Andrew D. Bolton.
Ph. D.
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Montplaisir, Lisa Marie. "Opportunities for learning in an introductory undergraduate human anatomy and physiology course." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280438.
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The purpose of this study was to explore the course conditions that support the development of meaningful student learning in an introductory undergraduate human anatomy and physiology course. The study was conducted during an 8-week summer-session at a small mid-western university. Classroom observations and taped recordings of class sessions were used to determine content episodes within the instructional unit, opportunities for learning created by the instructor, demonstrations of information processing by the students, and the ways in which the instructor used the Personal Response System (PRS). Student interviews were used to determine students' level of understanding of pre-test and post-test items. Student interviews and a questionnaire were used to determine students' perceptions of the PRS as a learning tool. Findings reveal that the instructor had different expectations of students when posing verbal questions in-class than he had when posing PRS questions. The use of verbal questions did not permit demonstrations of student understanding; however, the use of the PRS did result in demonstrations of student understanding. Questions posed via the use of the PRS were categorized according to cognitive level. The cognitive level of the questions increased with time over the instructional unit and within the content episodes. Students demonstrated deeper understanding of the topics after instruction than they did before instruction. Students reported more in-class thinking about the content, more discussion of the content with their neighbors, more regular class attendance, more opportunities for deeper learning, and a general preference for the PRS over traditional lectures. Findings of the study indicate that the instructional decisions about the use of questions influences the opportunities for students to process information and demonstrate their understanding of the content and that students valued these opportunities. A better understanding of the conditions that promote meaningful student learning may help us make decisions that result in improved student learning in our own classes.
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Borgström, Juliana. "Cyclical Women : Menstrual Cycle Effects on Mood and Neuro-Cognitive Performance." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17447.
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During roughly forty years of a woman’s life-span, the fertile female human body prepares itself monthly for the possibility of pregnancy. Science has shown that the fluctuation of the sex steroids progesterone and estrogen have a crucial role in the female body's physiology, determining the menstrual cycle and its general phases. This biological dance of hormones governing the cycle influences a lot of physical, mental and cognitive aspects of life for a fertile ovulating woman. Although the question of whether these changes also affect women's cognitive performance is still unclear, some evidence has been gathered that could bring us closer to answers. Recent research findings show that this hormonal interplay might have a significant role in cognitive and psychological development - modulating brain activity, cognitive performance, higher cognition, emotional status, sensory processing, appetite and more. This thesis aims to uncover to what extent the menstrual cycle affects brain functions, neurobiology, mood, well-being and cognitive performance in menstruating cisgender women.
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Bricolo, Emanuela. "On the representation of novel objects : human psychophysics, monkey physiology and computational models." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10620.
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Nielsen, Helen L. "Emotion experience and physiology in response to masked and non-masked presentations of emotional pictures." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280373.
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Recent theories propose that subtle emotional feelings can guide decision-making when insufficient information about the source of those feelings exists. To assess whether emotion experiences possess the properties necessary to play this functional role, subjects in the present study reported on feelings elicited by visually masked emotional pictures. Potential sources of individual differences in the ability to discriminate subtle "gut feelings" were also explored. 16 long-term meditators and 18 non-meditators viewed a series of pictures with pleasant, neutral, and unpleasant content, both masked and nonmasked, and reported on experienced valence and arousal, while measures of skin conductance (SCR), facial electromyography (EMG), and heart rate (HR) were simultaneously recorded. Masked emotional pictures did not elicit discriminatory SCR or EMG responses. HR discriminated among masked pictures by arousal, but not by valence. Both meditators and controls discriminated among masked stimuli in self-reported arousal, but only non-meditators demonstrated accurate valence discrimination. Unpleasant pictures were better discriminated from neutral pictures than were pleasant pictures. Ability to detect feelings elicited by masked stimuli was unrelated to heartbeat detection ability, cardiac vagal tone, or self-reported attention to emotional states, though self-reported emotional clarity predicted better arousal discrimination. It is proposed that awareness of emotion experience may involve both a visceral awareness and a non-visceral awareness of feeling qualities. Long-term meditation practice of the type adopted by participants in the present study, with its focus on the former, may reduce access to non-visceral feeling states.
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Ash, Ruth. "Iron status, cognitive function and physical fitness in British adolescent girls." Thesis, King's College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272220.
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King, Audrey E. "Effects of Age on Cognitive Performance While Sitting and Walking at a Treadmill Workstation." Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1527848728899635.
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García, Aguirre Ana I. "An evaluation of cognitive deficits in a rat-model of Huntington's disease." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8827.
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The purpose of this thesis was to develop methodology by which treatments for the cognitive impairments in Huntington's disease (HD) could be tested. As such, the thesis focused mainly on evaluating rats with quinolinic acid (QA) lesions of the striatum, as this manipulation mimics some aspects of the neural damage in Huntington's disease, to try to identify cognitive deficits of HD resulting from cell loss in the striatum. In the first part (Chapters 3-5), the role of the striatum in implicit memory was investigated. Chapter 3 compared the performance of rats and humans on a reaction time task that evaluated implicit memory by presenting visual stimuli with differing probabilities which change over time. Although rats made higher percentage of incorrect responses and late errors, both groups showed a similar pattern of reaction times. Chapter 4 investigated whether implicit memory (the computation of probabilities to predict the location of a stimulus) was affected by selective blockade of dopaminergic transmission at the D1 or D2 receptors by SCH-23390 and raclopride, respectively. Reaction times were slower with SCH-23390 and raclopride, but only SCH-23390 reduced errors to the least probable target location. Chapter 5 used the same task to evaluate implicit memory in rats with QA lesions of the dorsomedial striatum (DMS). Implicit memory was not affected by lesions of the DMS, which suggested that once a task that requires implicit memory has been learned, the DMS was not involved in sustaining the performance of the task. The second part of this thesis (Chapter 6), explored the contribution of the DMS in habit formation. DMS lesioned rats did not show habitual responding, and were not impaired in learning a new goal-directed behaviour. The third part (Chapters 7 and 8), investigated the role of the dorsal striatum in reversal learning, attentional set-formation, and set-shifting. Dorsal striatum lesioned rats were not impaired in reversal learning, but had a diminished shift-cost, which suggested that dorsal striatum lesions disrupted the formation of attentional sets. These results showed that although QA lesions of the dorsal striatum mimic some aspects of the neural damage in HD, they did not result in the same cognitive deficits observed in patients with HD, at least using the tasks presented in this thesis. However, other animal models of HD could be evaluated using the different tasks presented in this thesis to continue the search of a reliable animal model of HD in which treatments for the disease could be evaluated.
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Fadlallah, Hussein. "On the cognitive modulation of Vestibulo-Oculomotor performance." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23395.
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The object of this study was to investigate the scope of cognitive control over vestibulo-ocular reflex (VOR) performance during rotational vestibular stimulation. Human subjects, with head fixed to the body, were rotated in the dark through 20$ sp circ$ at 40$ sp circ$/s while trying to "look" at an earth-fixed target which was viewed straight ahead just before extinguishing the lights. During this rotation an apparent error of performance was systematically introduced by displacing this target at constant velocity through 12$ sp circ$, either in the same direction as the subject (Diminishing paradigm), or in the opposite direction (Augmenting paradigm). After cessation of rotation the target was re-illuminated and the subject allowed to see the final positional "error" of his/her oculomotor performance. During each trial they were asked either to try and CORRECT or NOT to CORRECT for the extrinsically induced "errors". In a subsequent, series of experiments, 2 hrs of synchronous rotation of the subject and the surrounding visual scene was used to produce adaptive attenuation of the VOR ($ approx$26%). The central component of the second experimental series was performance of the gaze stabilization test described above, conducted on the adapted subjects. (Abstract shortened by UMI.)
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Macleod, Mairi S. "Cognitive ageing and the role of the frontal lobes in prospective memory and planning." Thesis, University of Aberdeen, 2001. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU137019.
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A recent theory postulates that the cognitive functions associated with the frontal lobes are likely to selectively deteriorate with age (West, 1996). In line with this theory, it was predicted that an age-related decline in measures of prospective memory and planning would be observed. In order to investigate this hypothesis, a series of five experiments were conducted using groups of young, middle aged and older normal participants. In Experiment 1, participants were asked to follow a recipe while remembering to do various prospective memory tasks at the same time. Older participants performed significantly worse on all measures of prospective memory. Significant age differences in measures of planning were observed in the computerised &'34;Tower of London&'34; planning task in Experiment 2. In Experiment 3, participants were given an open-ended planning task involving allocating a list of tasks to three friends. Older participants made significantly more overall planning errors. In Experiment 4, few age differences were observed in general executive function. In Experiment 5, the role of attention in prospective memory and planning was examined. Older participants performed significantly worse than the younger participants at the prospective memory and planning tasks. Speed of information processing was more highly associated with performance on the planning and prospective memory tasks than the attentional measures. There was not enough evidence available from the two patient studies to suggest that prospective memory was differentially impaired in patients with frontal lesions. The overall results confirmed the experimental hypothesis that there is an age-related decline in prospective memory and planning. However, the extent to which these age-related declines can be attributed to selective declines in the frontal lobes remains unclear.
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Vinckier, Fabien. "Physiologie et physiopathologie de la reconnaissance visuelle des mots." Paris 6, 2012. http://www.theses.fr/2012PA066547.
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La lecture est une capacité culturelle d’apparition récente mais il existe une spécialisation cérébrale pour cette fonction. En particulier, une aire cérébrale située au sein du cortex occipitotemporal gauche semble critique pour l’analyse visuelle des mots : « l’aire de la forme visuelle des mots » (VWFA). Dehaene et Cohen ont suggéré que le développement de fonctions culturelles récentes, comme la lecture, pourrait s’appuyer sur le recyclage de mécanismes plus anciens. Notre travail s’inscrit dans cette perspective et se fonde sur un modèle de la reconnaissance visuelle des mots, le modèle LCD. Dans la continuité des travaux ayant conduit à ce modèle, nous avons cherché à caractériser l'architecture fonctionnelle de la VWFA, l'intégration de ce système au sein d'un réseau cortical plus vaste et les perturbations pathologiques de ce réseau. Notre modèle se caractérise par un haut niveau d'organisation spatiale et fonctionnelle. Nous avons testé cette prédiction en IRM fonctionnelle chez le sujet sain et mis en évidence un gradient de complexité des patterns reconnus au sein de la VWFA. Puis, nous avons cherché à mieux définir les limites du système expert de reconnaissance des mots. Nous nous sommes intéressés aux processus cérébraux de suppléance mis en place lorsque ce système est mis en échec en montrant le recrutement du cortex pariétal chez le sujet sain et en étudiant l'impact de lésions cérébrales pariétales, ou d’une dysconnectivité fonctionnelle, sur ces processus. Nous espérons que ce travail aura permis de mieux caractériser le développement des fonctions culturelles récentes au travers de l’étude des corrélats neuronaux de la lecture
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Parker, Tonya Moreland. "Recovery of motor and cognitive function following concussion /." view abstract or download file of text, 2006. http://proquest.umi.com/pqdweb?did=1188883691&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2006.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 113-119). Also available for download via the World Wide Web; free to University of Oregon users.
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Tomie, Jo-Anne B., and University of Lethbridge Faculty of Arts and Science. "Cognitive behavior of rats with thalamic lesions." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1994, 1994. http://hdl.handle.net/10133/60.
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The objective of this thesis was to test the idea that medial thalamic nuclei are part of a "memory circuit" in the brain. Rats received lesions of the anterior (ANT) or medial dorsal (MD) thalamic nuclei and were tested on two spatial tasks, a nonspatial configural task, and spontaneous and amphetamine-induced acitivity. The thalamic rats were impaired on the spatial and conifural tasks, ans some of the thalamic groups were slightly hyperactive after administration of amphertamine. The deficits were not large and could not be unequivocally attributed to the ANT or MD damage. The results question the role of the ANT or MD in the behaviors studied. It is suggested that the deficits obtained after thalamic damage may be nonspecific and it is concluded that the results do not support the notion that thalamic structures have a primary role in memory.xi, 187 leaves : ill., plates ; 29 cm.
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Calado, Vanessa Tome Gonçalves. "Desempenho de indivíduos acometidos por traumatismo cranioencefálico no teste n-back auditivo." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5162/tde-03012014-150743/.
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INTRODUÇÃO: O termo memória operacional (MO) refere-se a um constructo cognitivo capaz de armazenar e manter a informação acessível para uso determinado por um tempo limitado, possibilitando a manipulação de diversas informações simultâneas e sequenciais como operações matemáticas longas ou complexas, compreensão de palavras pouco frequentes, extensas ou frases complexas. A linguagem está entre as funções cognitivas que dependem do funcionamento da memória operacional e pode estar comprometida em várias condições patológicas, dentre elas o traumatismo cranioencefálico (TCE). Dados da literatura referentes a essa população ainda são restritos ou pouco consistentes. OBJETIVOS: investigar se o teste n-back é uma medida válida para identificar o déficit de memória em pacientes com TCE, estabelecer nota de corte e curva ROC do teste n-back, comparar o desempenho entre os indivíduos saudáveis e aqueles que sofreram TCE, comparar o teste n-back com os testes de linguagem e aspectos da lesão neurológica, tais como gravidade e tempo, tempo de coma e localização hemisférica da lesão nos resultados para verificar o desempenho e a relevância na separação dos casos em pacientes e controles.MÉTODOS: 53 indivíduos brasileiros (26 adultos com TCE e 30 adultos saudáveis) foram avaliados por bateria de estímulos verbais auditivos para verificar diferenças inter-grupos na capacidade de processamento da memória operacional, quanto ao numero de respostas corretas (acurácia), capacidade máxima de processamento na memória operacional (span) e também verificar a relação da memória operacional com habilidades linguísticas, através da comparação de testes. RESULTADOS: na comparação entre os pacientes e os indivíduos do grupo controle observou-se diferença estatisticamente significante entre os grupos tanto para os testes de base quanto para os resultados do n-back. Os grupos foram estatisticamente pareados em relação às variáveis sócio-demográficas (idade, escolaridade e gênero). O modelo estatístico com as variáveis do teste n-back demonstrou ótima separação dos casos em pacientes/ controle com a área sob a curva ROC de 89%. O modelo também mostrou convergência com os testes de linguagem para compreensão auditiva de sentenças, fluência verbal e aspectos discursivos-pragmáticos e com o nível cognitivo. O lado da lesão foi estatisticamente significante para o n-back, fluência verbal e discurso conversacional. CONCLUSÃO: Os resultados mostram que o n-back na maneira como foi desenhado é capaz de diferenciar os indivíduos alterados e os normais na habilidade de memória operacional. No estudo foi possível discriminar o comportamento de indivíduos com lesão encefálica adquirida e indivíduos saudáveis quanto à medida de acurácia e capacidade máxima de manipulação da informação na memória operacional. Esse comportamento reflete o funcionamento linguístico e cognitivo que se correlaciona com o mecanismo de memória operacionalINTRODUCTION: The term working memory (WM) refers to a construct cognitive capability of storing and keeping information on line to a determined use for a limited time, enabling the manipulation of diverse simultaneous and sequential information such as long or complex mathematical operations, comprehension of less frequent words, extensive or complex sentences. The language is among the cognitive functions which depends on the operational memory behavior and may be engaged in many pathological conditions, among them the TBI (traumatic brain injury). Literature dada relative to such population are still restrict or weak. AIM: investigate whether the n -back task is a valid measure for identifying memory deficits in patients with TBI; establish cutoff and ROC curve of n-back task; to compare performance between normals individuals and those who have suffered TBI; to compare n-back task with tests of language and aspects of neurological injury, such as severity, coma and hemispheric laterality of the lesion to verify the performance and relevance in the separation of cases. METHODOS: 53 individuals Brazilians (26 adults with TBI and 30 healthy adults) were assessed by a battery of auditory verbal stimuli for detecting differences between groups in the processing capacity of working memory, as the accuracy and span also check the relationship of working memory to language skills, through the comparison tests. RESULTS: in the comparison between patients and control subjects was observed statistically significant differences between groups thus to the tests as the basis tests as to results of the n -back. The groups were statistically matched in relation to socio-demographic variables (age, education and gender). The statistical model with variables of the n -back test showed good separation of cases where patients / control with the area under the ROC curve of 89 % . The model also showed convergence with language tests for auditory comprehension of sentences, verbal fluency and pragmatic - discursive aspects and the cognitive level. The side of the lesion was statistically significant for the n -back, verbal fluency and conversational discourse. CONCLUSION: the results demonstrated that the n-back on the way it was designed is able to distinguish the changed individuals and the normal on the working memory ability. On the study it was possible to discriminate the behaviors of individuals with acquired brain injury and healthy individuals regarding the accuracy and maximum capacity of manipulating information on the working memory. Such behavior reflects the linguistic and cognitive function which correlates with the working memory mechanism
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Leal, Sharon. "Central and peripheral physiology of attention and cognitive demand : understanding how brain and body work together." Thesis, University of Portsmouth, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424257.
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Saimpont, Arnaud. "Cognition motrice et vieillissement : aspects fondamentaux et cliniques." Dijon, 2009. http://www.theses.fr/2009DIJOS050.
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L’étude des représentations du mouvement via des paradigmes basés sur l’imagination ou l’observation d’actions constitue un moyen unique d’accéder au contenu cognitif - comme la planification ou la programmation - du mouvement, en s’affranchissant des informations sensorielles et motrices liées à son exécution réelle. Dans cette thèse, nous nous sommes intéressés au vieillissement des capacités de représentation - ou de simulation mentale selon Marc Jeannerod - du mouvement. Dans la première étude, nous avons plus spécifiquement exploré l’évolution avec l’âge du contenu non conscient - en lien avec la programmation - de la simulation mentale. A l’aide d’une tâche où les sujets devaient déterminer la latéralité de mains gauches et droites présentées dans différentes orientations, nous avons montré que les personnes âgées avaient des difficultés à simuler implicitement des mouvements du membre supérieur, et ce d’autant plus que ces mouvements étaient contraignants au niveau biomécanique. Nous avons également mis en évidence que les représentations des mouvements du bras non-dominant était plus affectées que celles concernant le bras dominant. Dans la deuxième étude, nous nous sommes plus particulièrement intéressés aux représentations conceptuelles du mouvement, en rapport avec la planification de l’action. Les participants devaient replacer dans l’ordre des images représentant les différentes actions nécessaires pour se relever du sol. Là encore, nous avons montré que les sujets âgés avaient plus de difficultés que les jeunes à simuler mentalement une séquence motrice complexe. Enfin, dans une dernière étude, nous avons exploré l’impact d’une pratique d’observation du mouvement, complémentaire à une pratique physique, sur l’apprentissage / réapprentissage du relevé du sol chez des personnes âgées à risque de chute. Le nombre de personnes capables de se relever a augmenté significativement à l’issue du programme d’entraînement dans le groupe ayant suivi cette approche. Cependant, cette amélioration de la performance ne s’est pas révélée plus importante que dans un groupe contrôle ayant suivi un entraînement physique seul. Les deux premières études ont donc montré que les processus de simulation mentale du mouvement sont altérés avec l’âge, notamment en ce qui concerne les actions complexes. Ces résultats soulignent le rôle des composantes centrales de l’action dans le déclin des performances motrices associé au vieillissement. La dernière étude n’a pas révélé d’impact significatif d’une pratique d’observation complémentaire à une pratique physique, dans l’acquisition d’une séquence motrice complexe. La pratique mentale - basée sur l’imagerie motrice ou l’observation - devrait se restreindre à des mouvements relativement simples avec des populations âgéesThe study of movement representations through experimental paradigms based on action imagination or action observation is interesting to access to the cognitive content - like planning and programming - of an action, without being perturbed by the sensory and motor information associated with the actual execution. In this thesis, we were interested in studying the aging of movement representations - or mental simulation of movements (Jeannerod, 2001). In the first study, we have more specifically explored the age-related changes of the non conscious content - related to action programming - of the mental simulation. By means of a task where the subjects had to judge the laterality of left and right hands presented in different orientations, we have shown that elderly people were impaired in implicitly simulating upper-limb movements, particularly movements requiring strong biomechanical constraints. We have also revealed that the movement representations of the non-dominant arm were more affected by aging than those of the dominant arm. In the second study, we were more particularly interested in the conceptual representations of the movement, those in relation with action planning. The participants had to put in order images representing the different actions necessary to perform to rise from the floor. Here too, we have shown that the elderly subjects had more difficulties than their younger counterparts in mentally simulating this complex motor sequence. Finally, in the last study, we have investigated the impact of a mental practice based on action observation, complementary to a physical practice, on the learning / relearning of the “rising from the floor”, in elderly people at risk of falling. The percent of people able to rise has significantly increased at the end of the training program in the group which has followed this method. However, this increase in performance was not significantly more important than in a control group which has only followed a physical training. Thus, the first two studies have shown that the processes of the mental simulation of movement are impaired with advancing age, especially when complex actions have to be simulated. These results highlight the role of the central components of action in the age-related decline of motor performances. The last study has not revealed a significant impact of an observational practice complementary to a physical practice in the acquisition of a complex motor sequence. The mental practice - based on motor imagery or observation - should be limited to relatively simple movements with elderly people
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KIM, CHUL-HO. "THE EFFECTS OF HYPOXIA AND EXERCISE ON PHYSIOLOGICAL AND COGNITIVE PERFORMANCE." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1311015088.
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Miller, Jennifer Nicole. "Acute Exercise and its Effect on Cognitive Performance in Sleep Deprived Individuals: A Review of Literature." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/honors/101.
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This literature review observes seven different studies that researched the effects of exercise on some measure of cognitive or psychological performance when sleep deprived. The purpose of this review is to consolidate the results of various exercise protocols on the effects of sleep deprivation to make a general conclusion regarding the effect on cognition. This will give insight into the future of research regarding how exercise may combat performance decrements seen when sleep deprived. There are several inconsistencies among current research concerning exercise and sleep deprivation; a standard needs to be created so the results of these studies can be extended to a larger population.
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Roy, Jefferson Edward. "Signal processing by vestibular nuclei neurons : dissociating sensory, motor, and cognitive influences." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84430.
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The vestibular sensory apparatus and associated vestibular nuclei are generally thought to encode angular head velocity during our daily activities. However, in addition to direct inputs from vestibular afferents, the vestibular nuclei receive substantial projections from cortical, cerebellar, and other brainstem structures. Given this diversity of inputs we asked: how are the responses of vestibular nuclei neurons to head velocity modified by these additional inputs during naturally occurring behaviours? Here we have focused on three specific classes of neurons in the vestibular nuclei: (1) vestibular-only (VO) neurons which are thought to mediate, at least in part, the vestibulocollic reflex (VCR); (2) position-vestibular-pause (PVP) neurons which mediate the vestibuloocular reflex (VOR), and; (3) eye-head (EH) neurons, which are thought to mediate pursuit eye movements.We first characterized neuronal responses to passive rotation in the head-restrained condition, and then released the head to record the discharges of the same neurons during self-generated head movements. VCR interneurons (VO neurons) faithfully transmitted head velocity signals during passive head motion, but their responses were greatly attenuated during all behaviours during which the monkey's behavioral goal was to move its head relative to the body. Moreover, the attenuation occurs only when neck proprioceptive inputs match those predicted by the neck motor command. We propose that the sensory-motor matching is meditated by interconnections with the cerebellum. Our findings indicate that the VCR is suppressed during active head movements, but remains responsive to unexpected head perturbations. In contrast, VOR interneurons (PVP neurons) faithfully transmitted head velocity signals when the animal stabilized its gaze, regardless of whether the head motion was actively or passively generated; their responses were attenuated only when the monkey's behavioral goal was to redirect its axis of gaze relative to space. We propose that efference copies of oculomotor/gaze commands are responsible for the behaviourally dependent modulation of PVP neurons (and by extension the VOR) during gaze redirection. Finally, the activity of EH neurons was recorded during head-restrained smooth pursuit and eye-head gaze pursuit. EH neurons were not influenced by error terms and their activity was best described by an eye movement-based model. In addition, during gaze pursuit EH neurons were found to encode gaze and head movement-related signals. Furthermore, neuron responses could be predicted by their head movement sensitivity during passive whole-body rotation in the dark and gaze movement sensitivity during smooth pursuit, regardless of the stimulation condition. We propose that EH neuron responses reflect the summation of head movement information fro
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Fisher, Abigail. "Relationships between physical activity and motor and cognitive function in young children." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/713/.
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Background: There is evidence suggesting a relationship between physical activity and movement skills in adolescents. Evidence, primarily from animal and older adult data, suggests that physical activity can improve cognitive function. Both motor and cognitive function are essential components of school readiness. If these relationships exist in young children, promotion of physical activity may have a significant impact on school readiness and academic achievement. Participants and Methods Study 1: 394 children (mean 4.2 SD 0.5 years; 209 boys/185 girls) were recruited from 36 Glasgow preschools. Physical activity (PA) was measured using the Actigraph accelerometer, movement skills (MS) were assessed using a test based on the Movement Assessment Battery. Studies 2-4: 64 children (mean age 6.2 yrs SD 0.3; 33 boys / 38 girls) were recruited from 6 Glasgow primary schools. Psychological outcome measures were the Cambridge Neuropsychological Test Battery (CANTAB) (working memory), the Attention Network Test (reaction time) the Cognitive Assessment System (CAS) (executive function), and the short form of Connor’s Parent Rating Scale (CPRS:S) (behaviour). Physical activity was measured using the Actigraph GT1M accelerometer. A specialist and trained teacher-led physical activity intervention (active games) was run in intervention schools 2 hours per week for 10 weeks. The control PE sessions were specialist and teacher led standard curriculum, increased to 2 hours per week. Results: Study 1: There was a statistically significant, but very weak (r 0.18, p <0.001), correlation between MS and PA. Boys and girls in the highest quartile for MS had significantly greater time spent in MVPA than girls and boys and girls in the lowest quartile, but this difference was small; median difference between girls in Q4 and Q1 0.9%: 95% CI 0.2-1.6% p 0.01), median difference between boys in Q4 and Q1 (median difference 0.9% 95% CI 0.0-0.2% p 0.04). Studies 2-4: Test and 3 week retest intraclass correlations (ICC) from the Cambridge Neuropsychological Test Battery (CANTAB) and Attention Network Test (ANT) suggest these measures are not sufficiently reliable in to be used an outcome in a future RCT in this age group (CANTAB spatial span r 0.51 p<0.001; spatial working memory r 0.49 p<0.00.1; strategy r 0.08, p<0.52) (ANT reaction time 0.32 p<0.05; accuracy 0.62, p<0.001). The CAS was accepted well by young children, has good previously established reliability, and would be a suitable outcome measure for a full scale RCT. There was no significant difference between the intervention and control group change in CAS scores (Full scale t=-0.74, p=0.48) or any of the subscales (p all >0.05). Physical activity was significantly higher during the intervention, than the control physical education (PE) sessions (median difference 628 cpm 95% CI 460, 786 p= <0.0001). During the standard curriculum PE sessions children in the control group spent 58% of their monitored time in sedentary behaviour. The existing data suggest that a 10 week intervention may improve spatial working memory (t=2.78, p 0.01) and aspects of behaviour (CPRS:S Cognitive Problems/ Inattention (t=2.00 p=0.04) in this age group, but further research in larger samples, with a more robust measure of SPW would be required to confirm these findings. The data allowed a power calculation for a future full scale RCT to be calculated (based on the CAS Planning scale), based on data from the current study a sample size of n=75 in each arm would be required, recruiting 100 in each arm to allow for drop-out. Conclusion The present data suggest only a weak relationship between MS and habitual activity, and questions the strong emphasis placed on movement skill development in the preschool curriculum. The present thesis provides data to adequately design and power a future full scale RCT to examine the effects of exercise and cognitive function.
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Perreault, Guylaine. "Social cognitive theory correlates of physical activity for women approaching menopause: A MONET study." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27480.
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Menopause marks the beginning of a period of life transition involving important health changes (North American Menopause Society [NAMS], 2004). It has been demonstrated that physical activity can partly compensate for some of the negative effects of estrogen deficiency (Kemmler et al., 2002). Unfortunately the majority of Canadian middle-aged women are inactive (Craig & Cameron, 2004). The years prior to the onset of the menopausal transition are an important time to modify activity levels, but very few studies have looked at the determinants of physical activity for women at this stage of their life. The purpose of this study was to investigate social cognitive theory correlates of physical activity for women that are approaching menopause. The initial methodology was based on a prospective research design. However, based on the decision to rely on a different measure of physical activity behaviour, the research design was modified to that of a cross sectional design. Within the cross sectional research design, 76 participants, enrolled in the MONET longitudinal study, completed measures of barrier self-efficacy, social support, environmental factors, moods, and exercise behaviour. Results showed that physical activity behaviour was significantly correlated to barrier self-efficacy (r = .33, p < .01) and anxiety (r = -.27, p < .05). In the light of these results, consideration should be given to the roles of self-efficacy and anxiety in the development of strategies to increase physical activity for women approaching the menopausal transition.
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Strehler, Anne. "The relationship between cognitive load, cognitive style and multimedia learning." Thesis, Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-10282008-120644/.
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