Dissertations / Theses on the topic 'Orienting effects'

Eleven experiments are reported which examine the effects of 90 dB (A) white noise on the processes which govern orienting of attention in visual space. The selectivity hypothesis argues that noise alters the priorities which govern stimulus selection so that subjectively dominant aspects of the environment are attended to more fully than those which are non-dominant. The applicability of this hypothesis is examined with regard to attentional orienting. Three experimental paradigms are used. The first involves a central cue presented immediately prior to target onset. In the absence of eye movements reaction times to expected targets are faster than to unexpected targets, but noise has no effects on performance. It is concluded that the power of the central alerting cue is focussing attention in a maximal fashion and noise has no further effect on policies of allocation. A second task design involves the presentation of positional information prior to a block of trials. Under such conditions subjects fail to maintain orienting as trials continue. Noise enhances the ability to maintain orienting over time. This effect is discussed in the light of the selectivity hypothesis. It is argued that the inability to maintain orienting is not due to the inhibition which arises as a result of successive responding. Rather it is due to the difficulty involved in maintaining an active orientation. The third paradigm involves orienting to specific locations on the basis of information stored in short-term memory. When recall of this information is aided by a visual warning signal occurring prior to target onset noise has no effect on performance. Without this signal, noise alters performance and these data are compared to predictions based upon the selectivity hypothesis. These effects are discussed in terms of a noise-induced change in the strategy of performance, rather than an effect which is mechanistic.

Navigation through the environment requires the ability to select relevant information from a multitude of irrelevant stimuli. Under conditions of processing conflict, attention and cognitive control processes bias sensory input based on internal goals. These processes are supported by the interplay of a fronto-parietal attention network that exerts a top-down influence on information processing and a superior temporal network that operates in parallel and that responds in a stimulus-driven manner to behaviorally salient stimuli. It is often reported that nicotine can enhance top-down attention control and reduce distraction. In experiments 1 and 2, the effects of increasing control demands on behavior were assessed using electrophysiological (EEG) and behavioral measures in an auditory number parity decision task with different levels of distraction. Participants made forced choice ‘odd’ or ‘even’ number decisions, while ignoring preceding or simultaneous novel distractors. A group of non-smokers was compared to overnight abstinent smokers (9 hours) and after nicotine intake via 2 mg nicotine tablet or via smoke-inhaled nicotine. The results revealed that preceding distractors impaired task performance due to orienting to and reorienting from the distractor. Simultaneous distractors did not cause orientation of attention (indicated by absence of a P3a Event-Related Potential) and produced smaller increments in response latencies. However, this type of complex novel stimulus initiated processes of memory updating that significantly impaired response sensitivity and accuracy. Nicotine withdrawal enhanced these distraction effects, whereas nicotine intake, particularly via smoking, normalized performance. In experiment 3, dichotic listening performance in a group of non-smokers was compared to abstinent smokers (12 hours) using behavioral, EEG and functional Magnetic Resonance Imaging (fMRI) measures. The perceptual salience of the stimuli was manipulated by systematically varying the Inter-aural Intensity Difference (IID) between them. The analysis pointed to distinct brain networks that differentially activate depending on the level of competition between sensory inputs and these effects were additionally modulated by nicotine withdrawal. Nicotine withdrawal impaired behavioral performance supported by evidence of enhanced use of memory and attention resources, and some evidence of task-independent default mode network activation. Overall, the findings suggest that withdrawal from nicotine, particularly in heavy smokers, is associated with impairments in cognitive control and that subsequent intake of nicotine serves mainly to normalize performance.

Due to numerous bottlenecks, the human brain is unable to consciously process all data available at the retina. To overcome these constraints, evolution has developed a system that breaks down retinal information into fragments and subsequently analyses them according to current goals and expectations. This biasing system is frequently referred to as attention. Yet despite a long history of itself having been the focus of analysis, there are a number of questions about attention that are clearly unanswered by the literature. Therefore, we wanted to address three problems highlighted by our literature review. Specifically, we wanted learn, (I) Are the effects of probabilistic expectations, when instructed either by spatial blocking of the target location or through a central cue, on response latencies the product of a ballistic, attentional process, or the product of an information theoretical decision-making process? (II) Can the inhibitory aspects of spatial attention be pre-deployed by using a central cue to manipulate prior expectations of where a task-irrelevant distractor is likely to appear? (III) What is the relationship between attention and eye movements?We investigated this last question by way of testing healthy participants on covert and overt versions of the behavioural paradigms designed to address questions I and II, and then in a neuropsychology patient who presented with hypometric saccades, we investigated if eye movements and attention can be dissociated. Experiments 1-4, showed that the effects of target probability - when either spatially manipulated or instructed through a central cue - can neither be fully accounted for by attentional accounts or information theoretical accounts. Additionally, the outcome of target probability is context dependent. That is, outcomes depend on how target probability was instructed. Experiment 5 showed that spatial inhibition cannot be endogenously deployed using central cues. Although we found that distractor suppression takes place when targets are invalidly cued, suggesting distractor suppression takes place during reorienting. Experiments 6-7 showed that attentional orienting can be preserved in the presence of oculomotor impairment, indicating eye movements and attention can be structurally dissociated. Whereas the results of experiments 1-5 are consistent with claims that covert and overt orienting are similarly affected by expectations due to a common attentional process. We conclude that expectations influence a mechanism common to overt and covert responses, but ultimately, both processes are distinct. In the discussion chapter, we discuss a number of future avenues of research,including how electrophysiology could be used to further understand the phenomena presented here. Overall, the contribution of this body of research is to illustrate that the relationship between top-down expectations and exogenous effects is extremely complicated, and are, currently, inadequately captured by present models of attention.

For their survival, humans and animals can rely on motivational systems which are specialized in assessing the valence and imminence of dangers and appetitive cues. The Orienting Response (OR) is a fundamental response pattern that an organism executes whenever a novel or significant stimulus is detected, and has been shown to be consistently modulated by the affective value of a stimulus. However, detecting threatening stimuli and appetitive affordances while they are far away compared to when they are within reach constitutes an obvious evolutionary advantage. Building on the linear relationship between stimulus distance and retinal size, the present research was aimed at investigating the extent to which emotional modulation of distinct processes (action preparation, attentional capture, and subjective emotional state) is affected when reducing the retinal size of a picture. Studies 1-3 examined the effects of picture size on emotional response. Subjective feeling of engagement, as well as sympathetic activation, were modulated by picture size, suggesting that action preparation and subjective experience reflect the combined effects of detecting an arousing stimulus and assessing its imminence. On the other hand, physiological responses which are thought to reflect the amount of attentional resources invested in stimulus processing did not vary with picture size. Studies 4-6 were conducted to substantiate and extend the results of studies 1-3. In particular, it was noted that a decrease in picture size is associated with a loss in the low spatial frequencies of a picture, which might confound the interpretation of the results of studies 1-3. Therefore, emotional and neutral images which were either low-pass filtered or reduced in size were presented, and affective responses were measured. Most effects which were observed when manipulating image size were replicated by blurring pictures. However, pictures depicting highly arousing unpleasant contents were associated with a more pronounced decrease in affective modulation when pictures were reduced in size compared to when they were blurred. The present results provide important information for the study of processes involved in picture perception and in the genesis and expression of an emotional response. In particular, the availability of high spatial frequencies might affect the degree of activation of an internal representation of an affectively charged scene, and might modulate subjective emotional state and preparation for action. Moreover, the manipulation of stimulus imminence revealed important effects of stimulus engagement on specific components of the emotional response, and the implications of the present data for some models of emotions have been discussed. In particular, within the framework of a staged model of emotional response, the tactic and strategic role of response preparation and attention allocation to stimuli varying in engaging power has been discussed, considering the adaptive advantages that each might represent in an evolutionary view. Finally, the identification of perceptual parameters that allow affective processing to be carried out has important methodological applications in future studies examining emotional response in basic research or clinical contexts.

For their survival, humans and animals can rely on motivational systems which are specialized in assessing the valence and imminence of dangers and appetitive cues. The Orienting Response (OR) is a fundamental response pattern that an organism executes whenever a novel or significant stimulus is detected, and has been shown to be consistently modulated by the affective value of a stimulus. However, detecting threatening stimuli and appetitive affordances while they are far away compared to when they are within reach constitutes an obvious evolutionary advantage. Building on the linear relationship between stimulus distance and retinal size, the present research was aimed at investigating the extent to which emotional modulation of distinct processes (action preparation, attentional capture, and subjective emotional state) is affected when reducing the retinal size of a picture. Studies 1-3 examined the effects of picture size on emotional response. Subjective feeling of engagement, as well as sympathetic activation, were modulated by picture size, suggesting that action preparation and subjective experience reflect the combined effects of detecting an arousing stimulus and assessing its imminence. On the other hand, physiological responses which are thought to reflect the amount of attentional resources invested in stimulus processing did not vary with picture size. Studies 4-6 were conducted to substantiate and extend the results of studies 1-3. In particular, it was noted that a decrease in picture size is associated with a loss in the low spatial frequencies of a picture, which might confound the interpretation of the results of studies 1-3. Therefore, emotional and neutral images which were either low-pass filtered or reduced in size were presented, and affective responses were measured. Most effects which were observed when manipulating image size were replicated by blurring pictures. However, pictures depicting highly arousing unpleasant contents were associated with a more pronounced decrease in affective modulation when pictures were reduced in size compared to when they were blurred. The present results provide important information for the study of processes involved in picture perception and in the genesis and expression of an emotional response. In particular, the availability of high spatial frequencies might affect the degree of activation of an internal representation of an affectively charged scene, and might modulate subjective emotional state and preparation for action. Moreover, the manipulation of stimulus imminence revealed important effects of stimulus engagement on specific components of the emotional response, and the implications of the present data for some models of emotions have been discussed. In particular, within the framework of a staged model of emotional response, the tactic and strategic role of response preparation and attention allocation to stimuli varying in engaging power has been discussed, considering the adaptive advantages that each might represent in an evolutionary view. Finally, the identification of perceptual parameters that allow affective processing to be carried out has important methodological applications in future studies examining emotional response in basic research or clinical contexts.

As an extension of previous studies (Urbanczyk, Angel, & Kennelly, 1988) examining the effects of unimanual finger tapping on lateralized cognitive tasks, lateral body orienting was added to an established dual task paradigm to generate differential hemispheric activation and shifts of attention. One hundred twenty university students retained sequences of digits or spatial locations for 20 seconds either alone or during finger tapping. By turning both head and eyes left or right, the hemisphere congruent with the sequences (LH for digits, RH for locations) or incongruent (vice versa) was activated. Activation had little effect on retention means but greatly affected resource composition supporting task performance. Congruent orientation produced significantly higher positive correlations between digit and location tasks than incongruent orientation. Females showed higher sequence retention correlations than males across both orienting groups. For females, congruent activation enhanced tapping rates and retention-tapping correlations. For males, activation affected neither of these. Discussed in light of neuroanatomical research, these results suggest that congruent attentional orienting may integrate regions of the less activated hemisphere into networks of the more activated hemisphere. This unification may occur more readily across the female corpus callosum, producing a greater dependence upon a general attentional resource than for males, who appear to depend more upon hemispheric resources.

Advances in simulation technology have brought about many improvements to the way we train tasks, as well as how we perform tasks in the operational field. Augmented reality (AR) is an example of how to enhance the user's experience in the real world with computer generated information and graphics. Visual search tasks are known to be capacity demanding and therefore may be improved by training in an AR environment. During the experimental task, participants searched for enemies (while cued from visual, auditory, tactile, combinations of two, or all three modality cues) and tried to shoot them while avoiding shooting the civilians (fratricide) for two 2-minute low-workload scenarios, and two 2-minute high-workload scenarios. The results showed significant benefits of attentional cuing on visual search task performance as revealed by benefits in reaction time and accuracy from the presence of the haptic cues and auditory cues when displayed alone and the combination of the visual and haptic cues together. Fratricide occurrence was shown to be amplified by the presence of the audio cues. The two levels of workload produced differences within individual's task performance for accuracy and reaction time. Accuracy and reaction time were significantly better with the medium cues than all the others and the control condition during low workload and marginally better during high workload. Cue specificity resulted in a non-linear function in terms of performance in the low workload condition. These results are in support of Posner's (1978) theory that, in general, cueing can benefit locating targets in the environment by aligning the attentional system with the visual input pathways. The cue modality does not have to match the target modality. This research is relevant to potential applications of AR technology. Furthermore, the results identify and describe perceptual and/or cognitive issues with the use of displaying computer generated augmented objects and information overlaid upon the real world. The results also serve as a basis for providing a variety of training and design recommendations to direct attention during military operations. Such recommendations include cueing the Soldier to the location of hazards, and mitigating the effects of stress and workload.
Ph.D.
Department of Psychology
Sciences
Psychology

Thesis (Ph.D.)--Indiana University, 2005.
Source: Dissertation Abstracts International, Volume: 66-08, Section: A, page: 2763. Adviser: Annie Lang. Title from dissertation home page (viewed Oct. 5, 2006).

We tend to shift our attention to wherever other people are looking, a phenomenon known as gaze-driven attentional orienting (Driver et al., 1999; Friesen & Kingstone, 1998). Gaze triggers attentional orienting primarily due to its social importance, and the reflexive shift of attention in the direction of another person’s gaze is widely documented (Friesen, Ristic, & Kingstone, 2004). Although much research has investigated the facial stimulus used to trigger orienting and how features of the face affect gaze cueing, few studies have examined the characteristics of the observer and how this might impact gaze driven attention. The present research used the gazecueing paradigm (Posner, 1980) to investigate whether the personality of the observer would influence reflexive orienting to gaze cues, and whether the observer’s personality characteristics would interact with stimulus characteristics such as perceived social dominance (experiment 1 and 2) and emotional expression (experiment 2) to impact the magnitude of the gaze cueing effect. Both reaction time and accuracy to a briefly presented target letter were measured to assess the magnitude of gaze cueing. The results showed that observer personality did not impact the magnitude of gaze cueing, although the effect of extroversion approached significance. Interestingly, the results also indicated that while dominance affects reaction time it does not affect accuracy. The effect of social dominance on gaze cueing was modulated by extroversion. Experiment 2 showed that emotional expressions did not influence gaze cueing magnitude, nor did emotional expression interact with either personality or perceived social dominance. The results provides some very preliminary suggestions that certain personality characteristics are associated with stronger gaze cueing and the effects of observer personality on gaze cueing magnitude should be further explored.

Perché le persone usano i social media? Applicando la teoria dell'auto-completamento simbolico (SCT; Wicklund & Gollwitzer, 1982), la presente tesi ipotizza che le persone utilizzino i social media per pubblicare contenuti auto-simbolizzanti e raggiungere quindi l'auto-completamento verso le proprie mete identitarie, cioè per condividere simboli di completezza e ripristinare obiettivi di identità incompleti (es., diventare un medico, essere una buona madre). Poiché i nuovi siti di social network hanno caratteristiche ideali per l'auto-simbolizzazione, le persone potrebbero persino essere attratte da tali siti proprio a causa di queste caratteristiche ideali (es., la possibilità di rivolgersi a pubblico in qualsiasi momento). Una prima serie di esperimenti ha testato l’ipotesi per cui gli studenti di medicina e giurisprudenza che percepiscono incompletezza riguardo ai propri obiettivi di identità professionale dovrebbero compensare mettendo in atto comportamenti di auto-simbolizzazione su Instagram, per esempio attraverso la pubblicazione di più simboli relativi alla loro identità obiettivi (es., camici bianchi). Lo Studio 1 ha rilevato che gli studenti di medicina incompleti, proprio come ipotizzato, pubblicano effettivamente più simboli relativi alla medicina rispetto agli studenti completi. Lo Studio 2 ha replicato questo effetto in un campione di studenti di giurisprudenza e ha confermato che i post auto-simbolizzanti degli studenti che si stanno completando online si riferiscono specificamente al loro obiettivo incompleto (cioè la carriera in giurisprudenza) e non ad altri domini completi e/o non pertinenti (cioè la vita universitaria). Lo Studio 3 ha dimostrato che gli studenti di medicina incompleti si impegnano a compensare attraverso la pubblicazione di simboli di completezza solo quando la loro incompletezza si riferisce al loro effettivo obiettivo di carriera e non ad altre carriere a cui non aspirano (es., una carriera in giurisprudenza). Guidato dalla teoria, un quarto esperimento ha esteso questi risultati testando due ipotesi correlate: (a) l'incompletezza dell'obiettivo dell'identità, in quanto stato orientato all'obiettivo, dovrebbe indurre effetti di orientamento, come l'impulsività durante la pubblicazione online, il disinteresse per i contenuti pubblicati dagli altri, irritazione e restringimento dell'attenzione; (b) tutti questi effetti di orientamento dovrebbero essere disinnescati attraverso la pubblicazione di un post auto-simbolizzante su Instagram (cioè un post che contiene simboli di raggiungimento dell'obiettivo e che quindi consente alla persona di ripristinare completezza). Lo Studio 4 ha supportato entrambe le ipotesi, dimostrando che l'incompletezza verso un obiettivo identitario provoca effetti di orientamento specifici volti a facilitare il raggiungimento dell'obiettivo e che la pubblicazione di contenuti auto-simbolizzanti sui social media può risolvere l’incompletezza e far scomparire tali effetti di orientamento. Un'ulteriore serie di studi ha portato la presente linea di ricerca un ulteriore passo avanti, verificando se le persone sono attratte dai social media proprio a causa delle loro caratteristiche ideali per l'auto-simbolizzazione. Sulla base di SCT, abbiamo identificato otto di queste caratteristiche ideali (es., la possibilità di trattare gli altri come un mero pubblico e non come un insieme di individui) e creato varie condizioni manipolate in cui i social media avevano o meno queste caratteristiche ideali, aspettandoci che l'assenza di esse avrebbe ridotto l'attrattiva dei social media e la loro efficienza nel soddisfare i bisogni di auto-completamento. Attraverso due esperimenti, abbiamo trovato un supporto parziale per entrambe queste ipotesi. Lo Studio 5 e lo Studio 6 hanno infatti scoperto che i social media con caratteristiche ideali per l'auto-simbolizzazione erano più attraenti di altri siti, oltre che più efficienti nel soddisfare i bisogni di auto-completamento. Vengono discusse le implicazioni teoriche e pratiche della presente ricerca per una migliore comprensione dei comportamenti dei social media, per prevenire le conseguenze negative dell'auto-simbolizzazione sui social media e per approfondire lo studio dei processi di auto-completamento.
Why do people use social media? Drawing on the theory of symbolic self-completion (SCT; Wicklund & Gollwitzer, 1982), the present work hypothesizes that people use social media to engage in self-symbolizing posting and reach self-completion, that is for sharing pertinent symbols of completeness and restore incomplete identity goals such as ‘becoming a physician’ or ‘being a good mother’. Further, since new social networking sites have ideal features for self-symbolizing, people may be attracted to using them right because of these ideal features (e.g., the possibility to address an audience at any time). The first set of experiments tested whether medical and law students who sense incompleteness concerning their professional identity goals engage in compensatory self-symbolizing on Instagram by increasing their posting of respective indicators of goal attainment (e.g., medical white coats vs. court clothes). Study 1 found that incomplete medical students post more medicine-related symbols on Instagram. Study 2 replicated this effect in a sample of law students and clarified that students’ self-symbolizing posts specifically relate to their incomplete goal (i.e., law career) and not to other non-pertinent domains (i.e., university life). Study 3 demonstrated that incomplete medical students only engage in self-symbolizing when their incompleteness refers to their career goal and not to other careers they do not aspire to (i.e., a law career). Driven by the theory, a fourth experiment extended these findings by testing two related hypotheses: (a) identity goal incompleteness—as a goal-oriented state—should induce orienting effects, such as impulsiveness when posting online, disinterest in others’ posted contents, irritation, and narrowing of attention; (b) all these orienting effects should be defused through the publishing of a self-symbolizing post on Instagram (i.e., a post entailing symbols of goal attainment). Study 4 supported both the hypotheses, demonstrating that identity goal incompleteness causes specific orienting effects intended to facilitate goal achievement and that posting self-symbolizing content on social media can resolve incompleteness and make these orienting effects disappear. An additional set of studies took the testing of our self-completion explanation a step further by strictly verifying whether people are attracted to social sites because of their ideal features for self-symbolizing. Based on SCT, we identified eight of these ideal features (e.g., the possibility to treat others as a mere audience) and created various manipulated conditions in which social media had or did not have these ideal characteristics, expecting that the absence of them would have reduced social media’s appeal and their efficiency in satisfying self-completion needs. Across two experiments, we found partial support for both these hypotheses. Study 5 and Study 6 indeed found that social media with ideal features for self-symbolizing were more appealing than other sites, as well as more efficient in satisfying self-completion needs. Theoretical and practical implications of the present research for a better understanding of social media behaviors, preventing negative consequences of self-symbolizing on social media, and deepening the study of self-completion processes are discussed.

In this dissertation the effects of variations in stimulus properties and CTOA, in auditory attention tasks were explored using recently developed approaches to EEG analysis including LIMO. The last experiment was structured using information theory, designing an effective experiment. Four studies were carried out using a number parity decision task, that employed different combinations of cueing Tone (T), Novel (N) and the Goal (G) stimuli. In the first EEG study, contrary to previous findings (Polich 2002, 2007) in control participants, no correlation between the time of a novel condition to the next novel condition and P300 amplitude was found. Therefore single trial across-subject averaging of participants’ data revealed significant correlations (r > .3) of stimulus properties (such as probability, frequency, amplitude and duration) on P300, and even r > .5 was found when N was an environmental sound in schizophrenic patients. In the second EEG study, simultaneously with fMRI recordings, the participants that showed significant behavioural distraction evoked brain activations and differences in both hemispheres (similar to Corbetta, 2002, 2008) while the participants, as a whole, produced significant activations mainly in left cortical and subcortical regions. A context analysis was run in distracted participants contrasting the trials immediately prior to the G trials, resulting in different prefrontal activations, which was consistent with studies of prefrontal control of visual attention (Koechlin 2003, 2007). In the third EEG study, the distractor noise type was manipulated (white vs environmental sounds) as well as presence or absence of scanner background noise in a blocked design. Results showed consistent P300, MMN and RON due to environmental noise. In addition, using time constants found in MEG results (Lu, Williamson & Kaufman, 1992) and adding the CTOA to the analysis, an information theory framework was calculated. After the simulation of the information of the experiment, a saddle indentation in the curve of the information measure based on the states of the incoming signal at around 300 ms CTOA was found. This saddle indentation was evident in more than 60 novel trials. In the fourth study, the CTOA and stimulus properties were manipulated in a parametric experiment. Based on the three studies, reducing complexity if the task (first study), using more than 60 stimuli in the novel conditions (third study). The CTOA randomly varying between 250 ms or 500 ms. Thirty-eight ANCOVA with 2 categorical and 1 continuous regressors were conducted and determined which time and channels elicited reliably signatures (p <.05) in the whole participants at short CTOA. Results revealed differences for the waveforms of current condition by depending on which condition appeared previously as well in terms of frequency and duration in scalp frontal electrodes (such as the second study). These results were interpreted as a consequence of switching between modes of attention and alerting states which resulted in the activation of frontal areas. Moreover, contextual analyses showed that systematic manipulation of stimulus properties allowed the visualization of the relationships between CTOA, executive function and orienting of attention.

The research presented in this thesis is an explorative study into the basic concepts and the effects of dance movement psychotherapy (DMP) intervention on the attunement behaviours of children and adolescents with autism spectrum disorders (ASD). From a retrospective analysis of positively evaluated single cases of DMP with ASD participants, movement markers of interpersonal relating behaviours have been formulated in terms of Social Engagement and Attunement Movement (SEAM) behaviours. These were organised into an observation scale, and used subsequently to generate nominal observation data on the behaviours of a small sample of children with ASD. Evaluation with the SEAM observation scale yielded a significant increase of SEAM behaviours in the course of the dance therapy. Retrospective analysis of the actions of the therapist throughout four single cases of DMP with ASD participants yielded a specific approach that was described as Shared Movement Approach (SMA). SMA has been specified as an improvisation based method of DMP that takes the child's interpersonal attunement and engagement behaviours as cues for the therapist to accommodate her interventions, so that the child's interpersonal relating behaviours are facilitated and supported. Through her kinaesthetically informed interventions the DMP therapist contributes to an increase of interpersonal engagement and attunement by the ASD participant from within the shared movement actions. The SEAM observation scale was explored on conceptual clarity and consistency in a group of independent movement analysts, and interrater agreement was used as an indication of its contents validity. An interval rating procedure with the SEAM scale yielded the best results on interrater agreement as expressed in Cohen's kappa. The Shared Movement Approach and the SEAM observation scale were then tested for replication of outcome on SEAM behaviours within four repeated single subject cases in a pilot study in a Dutch outpatient clinical setting. The outcome monitoring yielded the replication of increase of interpersonal relating behaviours as measured with the SEAM observation scale. Within subject therapy outcomes, although diverse in their individual profiles, were found to be significant when analysed with non-parametric tests. Group averages showed a significant increase of SEAM behaviours. The effects beyond therapy were evaluated with the somatic and social sub-scales of the Child Behaviour Checklist (CBCL) and the Social Responsiveness Scale (SRS), showing individual differences and a significant problem reduction on average. The outcomes as experienced by the juvenile participants were evaluated with the somatic and social sub-scales of the Youth Self Report (YSR), which on average showed a significant decrease of experienced social and somatic problems. The results obtained are discussed in view of current theories on experiential approaches and concepts for psychotherapy with an ASD population.

Attentional orienting involves two neuroanatomically and functionally separate components, the reflexive and voluntary attentional sub-systems, which interact to orient attention on the environment. Three experiments, in which a cueing paradigm was used, examined reflexive and voluntary orienting over later childhood development (i.e., 8--14 years old) in order to explore the mechanisms underlying the development of the control of attentional orienting. Experiments 1 and 2 explored whether reflexive and voluntary orienting develop in parallel, and examined the influence of cue predictability on attentional orienting during development. Experiment 3 explored the role of explicit instructions in the influence of cue predictability on voluntary and reflexive orienting. The results indicate that the development of attentional orienting over later childhood is a reflection of the operation of an underlying mechanism, general developmental changes in speed of processing. Apart from this mechanism, the efficiency of attentional orienting remains the same across age. In addition, the influence of cue predictability on attentional orienting reflects the operation of a low-level mechanism which operates independently of strategic influences; this mechanism may be covariance detection and judgment. The implications of these conclusions for modeling attentional orienting, and the development thereof, are considered.

Der Distraktoreffekt beschreibt eine Verlängerung der Fixationsdauer als Folge der Darbietung irrelevanter Störreize (Distraktoren). In der Dissertation wurde der Frage nachgegangen, ob sich der Distraktoreffekt funktionell auch im Rahmen des Konzepts der Orientierungsreaktion (OR – Sokolov, 1963) betrachten lässt. Reizeigenschaften wie Neuheit und Relevanz wurden in der Vergangenheit als wesentliche Auslösebedingungen einer OR diskutiert. Im Rahmen dieser Arbeit wurden beide Merkmale untersucht, um die Plausibilität des Zusammenhangs von Distraktoreffekt und OR empirisch zu testen. Hierfür kam in allen Studien ein experimentelles Paradigma zum Einsatz, bei dem Distraktoren blickkontingent während einer freien Bildbetrachtungsaufgabe dargeboten wurden. Der Einfluss von Neuheit wurde durch Untersuchungen zur Habituation des Distraktoreffekts geprüft. Die Ergebnisse der Studien ergaben deutliche Anzeichen einer Habituation im okulomotorischen Verhalten (Abnahme der Fixationsdauerverlängerung) sowie in elektrophysiologischen Parametern der kortikalen Verarbeitung des Distraktors, im Sinne einer Abnahme der N1 Komponente des EKPs. Somit konnte also eine Modulation durch Neuheit eines Distraktors nachgewiesen werden. Die Frage nach dem Einfluss von Relevanz wurde experimentell durch Manipulation aufgabenbezogener Relevanz von Distraktoren, durch Verwendung emotionaler Distraktorinhalte (unterschiedliche emotionale Gesichtsausdrücke) und durch Darbietung neutraler Distraktoren in einem emotionalen Kontext untersucht. In keiner der drei Studien konnten eindeutige Befunde, die für eine Modulation des Distraktoreffekts durch Relevanz sprechen, aufgezeigt werden. Zusammengenommen konnte der postulierte Zusammenhang von Distraktoreffekt und OR nicht bestätigt werden. Im letzten Teil der Arbeit wurde das Distraktorparadigma genutzt, um zu prüfen, ob Unterschiede in der Art der Verarbeitung und Aufmerksamkeitsausrichtung innerhalb einer Fixation die Verarbeitung eines Distraktors beeinflussen. Frühere Überlegungen aufgreifend (Pannasch & Velichkovsky, 2009) wurden Verarbeitungsunterschiede anhand des Musters von Sakkaden, die eine Fixation umgeben, operationalisiert. Die distraktorinduzierte Verlängerung der Fixationsdauer war am größten, wenn die betroffene Fixation in kurze vorhergehende und nachfolgende Sakkaden eingebettet war und am kleinsten im Kontext langer Sakkaden. In parallel aufgezeichneten elektrophysiologischen Daten zeigten sich Unterschiede zwischen den sakkadischen Kontextbedingungen vor allem als Variation der distraktorbezogenen P2 Komponente. Diese Ergebnisse bestätigten die Annahme, dass anhand des sakkadischen Kontexts Unterschiede in der Art bzw. dem Modus der Verarbeitung innerhalb einer Fixation identifiziert werden können und sich in Veränderungen von Verhaltensparametern und kortikalen Aktivitätsmustern der Distraktorverarbeitung widerspiegeln. Diese Ergebnisse unterstützen einerseits frühere Annahmen bezüglich funktioneller Unterschiede von Blickbewegungsmustern (Velichkovsky, Joos, Helmert, & Pannasch, 2005) und legen außerdem eine Beteiligung kortikaler Areale an distraktorinduzierten Prozessen der sakkadischen Hemmung nahe.

Abstract ORIENTIA TSUTSUGAMUSHI ANKYRIN REPEAT-PROTEIN FAMILY TARGETING OF THE HOST ENDOPLASMIC RETICULUM By Lauren VieBrock, B.S. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University Virginia Commonwealth University, 2015 Director: Jason A. Carlyon, Ph.D. Professor Microbiology and Immunology Scrub typhus is an understudied, potentially fatal febrile illness, which poses threat to one billion people annually in the Asia-Pacific region. The host-pathogen interactions that facilitate the intracellular survival of the etiologic agent, Orientia tsutsugamushi, are not well understood. The Orientia tsutsugamushi genome encodes a large number of ankyrin repeat-containing proteins (Anks), key virulence factors for other intracellular pathogens, as well as components for Type I (T1SS) and Type 4 secretion systems (T4SS), commonly used to deliver them. We sought to characterize the roles of the Anks in O. tsutsugamushi infection. In this study, we demonstrated that O. tsutsugamushi expressed all 20 anks and the genes for the T1SS, for which they are substrates. Many ectopically expressed Anks displayed a tropism for the host endoplasmic reticulum (ER). These results suggest the importance of the Anks and the ER to Orientia tsutsugamushi pathobiology. We demonstrated that O. tsutsugamushi tightly associated with the ER and induced ER stress and defects in protein secretion of its host cells. Therefore, we hypothesized that the ER-tropic anks expressed during the initial hours of infection are critical for establishing infection and do so by interacting with specific host cell targets to modulate host cell function to benefit intracellular survival. ER-tropic Ank4 was detected as expressed early in infection and was further characterized for its contribution to the alterations of the ER during infection. Bat3 was identified as a target of Ank4, and Ank4 expression correlated with a decrease in Bat3 protein levels, induction of ER stress, and defects in protein secretion. These effects were Ank4 F-box dependent, implicating polyubiquitination and proteosomal degradation of Bat3. As Ank4 colocalized with Bat3, a chaperone component of ER-associated degradation (ERAD) of misfolded proteins, ERAD function was measured in cells expressing Ank4. In an F-box dependent manner, Ank4 expression resulted in decreased degradation of a model substrate and indicated inhibition of the ERAD pathway. Similarly, we demonstrated that in O. tsutsugamushi infection, Bat3 levels were significantly reduced early in infection and ERAD degradation was inhibited. After several days of infection however, Bat3 levels and ERAD degradation had both recovered, suggesting temporal modulation of ERAD in infection. Taken together, these data suggest that O. tsutsugamushi has a large capacity to disrupt the host ER, exemplified by Ank4 mediated ERAD dysfunction by depletion of host Bat3.

In open skill sports and other tasks, decision-making can be as important as physical performance. Whereas many studies have investigated visual perception there is little research on auditory perception as one aspect of decision making. Auditory localisation studies have almost exclusively focussed on underlying processes, such as interaural time difference and interaural level difference. It is not known, however, whether semantic spatial information contained in the sound is actually used, and whether it assists pure auditory localisation. The aim of this study was to investigate the effect on auditory localisation of spatial semantic information. In Experiment One, this was explored by measuring whole body orientation to the words "Left", "Right", "Back", "Front" and "Yes", as well as a tone, each presented from left right, front and back locations. Experiment Two explored the effect of the four spatial semantic words presented either from their matching locations, or from a position rotated 20 degrees anticlockwise. In both experiments there were two conditions, with subjects required to face the position indicated by the sound location, or the meaning of the word. Movements of the head were recorded in three dimensions with a Polhemus Fastrak system, and were analysed with a custom program. Ten young adult volunteers participated in each experiment. Reaction time, movement time, initial rotation direction, rotation direction at peak velocity, and the accuracy of the final position were the dependent measures. The results confirmed previous reports of confusions between front and back locations, that is, errors about the interaural axis. Unlike previous studies, many more back-to-front than front-toback errors was made. The experiments provided some evidence for a spatial Stroop interference effect, that is, an effect on performance of conflicting information provided by the irrelevant dimension of the stimulus, but only for reaction time and initial movement direction, and only in the Word condition. The results are interpreted using a model of the processes needed to respond to the stimulus and produce an orienting movement. They suggest that there is an asymmetric interference effect in which auditory localisation can interfere with localisation based on semantic content of words, but not the reverse. In addition, final accuracy was unaffected by any interference, suggesting that these effects are restricted to the initial stages of response selection.

In open skill sports and other tasks, decision-making can be as important as physical performance. Whereas many studies have investigated visual perception there is little research on auditory perception as one aspect of decision making. Auditory localisation studies have almost exclusively focussed on underlying processes, such as interaural time difference and interaural level difference. It is not known, however, whether semantic spatial information contained in the sound is actually used, and whether it assists pure auditory localisation. The aim of this study was to investigate the effect on auditory localisation of spatial semantic information. In Experiment One, this was explored by measuring whole body orientation to the words "Left", "Right", "Back", "Front" and "Yes", as well as a tone, each presented from left right, front and back locations. Experiment Two explored the effect of the four spatial semantic words presented either from their matching locations, or from a position rotated 20 degrees anticlockwise. In both experiments there were two conditions, with subjects required to face the position indicated by the sound location, or the meaning of the word. Movements of the head were recorded in three dimensions with a Polhemus Fastrak system, and were analysed with a custom program. Ten young adult volunteers participated in each experiment. Reaction time, movement time, initial rotation direction, rotation direction at peak velocity, and the accuracy of the final position were the dependent measures. The results confirmed previous reports of confusions between front and back locations, that is, errors about the interaural axis. Unlike previous studies, many more back-to-front than front-toback errors was made. The experiments provided some evidence for a spatial Stroop interference effect, that is, an effect on performance of conflicting information provided by the irrelevant dimension of the stimulus, but only for reaction time and initial movement direction, and only in the Word condition. The results are interpreted using a model of the processes needed to respond to the stimulus and produce an orienting movement. They suggest that there is an asymmetric interference effect in which auditory localisation can interfere with localisation based on semantic content of words, but not the reverse. In addition, final accuracy was unaffected by any interference, suggesting that these effects are restricted to the initial stages of response selection.

碩士
國立政治大學
廣告研究所
98
Keyword advertising has become the largest source of revenue for search engines. Now, keyword advertising has developing into a new cross-media style. Mass media not only release advertising messages but also orient consumers to search more details of merchandise online. As the result, the study use Pluralistic Research Methodologies to investigate how to Increase consumers’ search intention. The first stage we use Focus Group Discussion to clarify the research questions. And do Depth interview with Industry to understand the Practical operation and the Success Factors. In the second stage, the study proceeded in experiment method. Two factors “Keyword Type” and “Product Type” are used to compose a 2X3 factorial design experiment, and then bring “Product involvement” and “Prior Product Knowledge” in as the Moderator. Furthermore, the study adopted “Memory in Advertising Message” and “Search Intention” as the depend variables. Result shows that, product involvement and prior product knowledge have a significant positive effect to the search intention. In addition, results of keyword type and product type are not remarkable overall. Keywords: Orienting-

This thesis reviews existing models of habituation of the orienting response (OR) and presents four experiments designed to clarify contentious issues in the existing literature. A new connectionist model of habituation is developed and its performance in various experimental situations simulated. Models created to account for habituation can be classified into two types: 1)Comparator models in which the subject compares an internal trace of past stimulation with current stimulation and the orienting response is an index of the disparity between the two. 2) The dual-process model in which habituation is the result of two independent processes of inferred habituation and inferred sensitisation acting within the stimulus-response (S-R) pathway. A major difference between the two types of model is that comparator models of habituation (Ohman, 1979; Sokolov, 1960; Wagner, 1981) postulate that the internal trace encodes extrapolatory or temporally predictive information about the stimulus series, while the dual-process model (Groves & Thompson, 1970) does not suppose that temporal information is encoded. Both the elicitation of a response by stimulus omission, and the effect of 1ST variability on the rate of habituation, are vital indicators of the merit of each approach. Only if both phenomena are demonstrated to exist must a valid habituation model incorporate a mechanism of temporal encoding. Prior evidence for a response to stimulus omission and an effect of 1ST variability on rate of habituation was inconclusive. Four experiments were conducted to examine these and related phenomena in habituation of the skin conductance response (SCR). It was concluded, from the results of these experiments, that both response to stimulus omission and an effect of ISI variability on the course of habituation had a significant effect at short ISIs (1- 2s) but no significant effect was at longer ISIs (>10s). A model of OR habituation was devised that was capable of incorporating the new results as well as other published results. A neural network or - connectionist modelling framework was chosen for this purpose, for its quantitative nature, ease of simulation and neurobiological plausibility. Five different connectionist models were constructed and simulations were performed to assess the performance of each model in experiments testing various temporal phenomena. It was concluded that a model incorporating delta-rule learning of physical features plus learning of temporal relationships by the learning of the interval between stimuli could most satisfactorily simulate the observed empirical results. The connectionist models and their performance in experimental simulations were related to traditional models of habituation.

Modafinil is a wakefulness-promoting drug that is becoming more commonly used for off-label for attentional enhancement in healthy individuals despite conflicting evidence to support this. The aim of the current study was to investigate the effects of modafinil on behavioural (reaction time & accuracy) and ERP (N1 amplitude) measures of the attentional alerting and orienting networks and also investigate any sex differences associated with these effects. The final sample consisted of 14 females and 22 males who were all healthy and met the screening criteria. Each participant completed two sessions differing by drug condition (200mg modafinil or placebo). The Attentional Network Task was used to assess the effects on both the alerting and orienting network and this task was completed at baseline and at 2.5 hours post-ingestion. As expected, reaction time decreased and N1 amplitude increased as cues became more informative. There was a small enhancement of the alerting network demonstrated by a significant decrease in reaction time from baseline to post-ingestion for central cues in the modafinil condition but not placebo. There was a small significant decrease in reaction time from baseline to post-ingestion for spatial cues but this is likely due to alerting enhancement rather than orienting as the effects were of similar size. Inconsistent to the hypotheses, males had a faster reaction time to all cue types when compared to females. Males also showed greater N1 amplitude after modafinil ingestion than placebo, indicating some sex differences in the effect of modafinil may be present. These results suggest that modafinil may have an enhancing effect on the alerting network but not the orienting network. The effects of modafinil on the orienting network has not been well studied so future research is required to confirm this finding. There also appears to be differential effects of modafinil on males and females, which also requires future investigation as this is the first study to look at these effects.

碩士
國立臺北教育大學
特殊教育學系碩士班
101
This study adopted the experimental design of a single-subject withdrawal research designs with A1-B1-A2-B2 model. One preschool child with autism and two typically developing children were recruited to form a play group to explore the effect of social orienting intervening. The results show that positive emotional exchange strategy is very effective to improve the social orienting behaviors (orienting to peers, eye-gazing, emotional reaction, calling name) and imitation of the child with autism.

碩士
國立交通大學
傳播研究所
100
The screen of television news contain multiple information components, so watching television is no longer just a single-screen information processing, multiple information components constantly influence viewers’ information processing and cognitive resource allocation. Based on the relevant cognitive psychological study, Limited Capacity Model of Mediated Message Processing (LC4MP) and psychophysiology, the research is focused on the orienting responses elicited by automatic processing during encoding. Besides, the research also explores audiences’ resource allocation s by different processing modes. We integrate the techniques of eye tracking and heart rate measuring to give us an insight into the effect between structural features and multiple information components on Television viewing. Two experiments are designed: The first experiment aims to observe whether the high amounts of tructural features of television news appeal more attention and keep impressive memory under the driving of automatic processing when watching two information components on TV simultaneously. The second experiment aims to explore whether different possessing modes (restriction on viewing anchor or video) can strength or weaken the influence of structural features. Results show that: First, the structural features of television news can result in improved attention, improved memory, and cardiac orienting responses. Second, under the mode of browsing, the viewing behavior is similar to the mode of video-viewing. Third, viewers are used to watch anchor at the first sight when multiple information components are presented. Last, possessing modes has significant influence on eye movements and recognition, but no interaction effect on structural features, which indicates the dominance of controlled possessing.

碩士
國立東華大學
海洋生物多樣性及演化研究所
100
Macrobrachium rosenbergiis the world's breeding the highest amount of one of three prawns, but still need to improve the environment in shrimp nurturing and strengthening the management. To determine the optimal condition for larval culture of this speices, the effects of stocking density, water exchange rate, photosynthetic bacteria and algal addition on growth, survival and water guality of juveniles were assessed. Photosynthetic strains used the 16SrDNA sequence analysis and results confirm for Rhodobium sp. First, the effects of the photosynthetic bacteria (Rhodobium sp.) at concentrations of 0, 103, 104, 105, 106and 107cells mL-1 on the M. rosenbergii juvenile survival rate is recorded using a control tank with unchanged water and lacking photosynthetic bacteria and algae. The effect on the juvenile freshwater prawn is then calculated with variables such as density of prawn present at 7, 10, 13 and 16 juveniles L-1 and variations of photosynthetic bacteria. 0 juveniles L-1 is control. The effect on the juvenile freshwater prawn is calculated with different treatments are zero-exchange ,change water and gain photosynthetic bacteria. The results indicate that Rhodobium sp. had significantly higher survival rates in tanks with concentrations the other groups than those in the 0 and 103 cells mL-1 tanks (p＜0.05); the growth rates in the103 cells mL-1 tanks had significant (p＜0.05). The seven groups in NH3-N, NO2-N, NO3 -N, PO4-P had no significant differences (p＞0.05). The 7 juveniles L-1 also had significantly higher survival rates in the tanks with 13 and 16 juveniles L-1 tanks (p＜0.05); the growth rates had no significant differences (p＞0.05). The water quality present in the 0 tanks had lower levels of NH3-N, NO2-N, NO3 –N and PO4-P (p＜0.05). The survival rates in the zero-exchange and change water were not significant (p＞0.05); the growth rates in the treatments had no significant differences (p＞0.05). The water quality present in the NH3-N had no significant differences (p＞0.05); PO4-P and NO3 －N in the change water had lower significant(p＜0.05)and NO2 －N in the zero-exchange had higher significant(p＜0.05). This report indicates that the tanks prosper best with a concentration of R. orientis at 104 ~ 107 cells mL-1and juvenile prawns densities of 7 juveniles L-1; zero water exchange in the tank with photosynthetic bacteria and algal can maintain a stable.