Psychology Commons^™

A Kinematic Analysis Of Visual And Haptic Contributions To Precision Grasping In A Patient With Visual Form Agnosia And In Normally-Sighted Populations, Robert Whitwell

Electronic Thesis and Dissertation Repository

Skilled arm and hand movments designed to obtain and manipulate objects (prehension) is one of the defining features of primates. According to the two visual system hypothesis (TVSH) vision can be parsed into two systems: (1) the ventral ‘stream’ of the occipital and inferotemporal cortex which services visual perception and other cognitive functions and (2) the ‘dorsal stream’ of the occipital and posterior parietal cortex which services skilled, goal-directed actions such as prehension. A cornerstone of the TVSH is the ‘perception-action’ dissociation observed in patient DF who suffers from visual form agnosia following bilateral damage to her ventral stream. DF …

Associations Between Hypothalamic-Pituitary-Adrenal Axis System Gene Variants And Cortisol Reactivity In Preschoolers: Main Effects And Gene-Environment Interactions, Haroon I. Sheikh

Electronic Thesis and Dissertation Repository

Exposure to stressful events during early development has consistently been shown to produce long lasting effects on the hypothalamic-pituitary-adrenal (HPA) axis, which may increase vulnerability to mood and anxiety disorders. Recently reported genetic association studies indicate that these disorders may be influenced, in part, by gene-environment interactions (GxE) involving polymorphisms within the corticotrophin-releasing hormone and monoaminergic system genes. However, little is known about how genetic variants and life stress work to shape children’s neuroendocrine reactivity and emerging symptoms. Therefore, the aim of this thesis is to examine main effects of candidate genes and GxE on the neuroendocrine stress response and …

Interesting Shapes Of Vegetables: Is It A Strategy To Promote Consumption Among Preschool Children?, Salma H. Alhabshi

Electronic Thesis and Dissertation Repository

This study highlighted the low intake of vegetables by preschool children and determined whether changing the shape of vegetables increased their level of consumption. A new strategy of repeated exposure to interesting-shaped vegetables was a step aimed at increasing vegetable consumption by increasing the fun element in having vegetables as snacks. Vegetables are the less desirable food in comparison to more attractive unhealthy choices available to children, and discovering a strategy to promote vegetables is considered an important step in nutrition. The primary aim was to explore the effect of repeated exposure (eight times) of shaped vegetables on consumption by …

Where Do I Know That? A Distributed Multimodal Model Of Semantic Knowledge, Kevin M. Stubbs

Undergraduate Honors Theses

As computers have grown more and more powerful, computational modeling has become an increasingly valuable tool for evaluating real world findings. Likewise, brain imaging has become increasingly powerful as is evidenced by recent fMRI findings which support the exciting possibility that semantic memory is segregated by modality in the brain (Goldberg et al., 2006b). The present study utilizes connectionist modeling to put the distributed multi-modal framework of semantic memory to the test, and represents the next step forward in the line of sensory-functional models. This model, based around the McRae et al. (2005) feature production norms, includes individual implementations of …

The Effect Of Exercise On Cravings And Ad Libitum Smoking Following Concurrent Stressors, Angela J. Fong

Electronic Thesis and Dissertation Repository

Quitting smoking itself is a stressor; it is likely that other stressors occur concurrently and deplete self-regulatory resources. Failure to cope leads to smoking relapse. Exercise has been shown to attenuate cravings and withdrawal symptoms in previous research and has yet to be examined following concurrent stressors. This study examined the effect of an acute bout of moderate intensity exercise on psychological withdrawal symptoms (PWS), cravings and ad lib smoking after concurrent stressors (i.e., temporary abstinence and depletion). Twenty-five smokers were randomized into exercise or passive conditions. Results showed PWS were significantly exacerbated after temporary abstinence and again after depletion …

Timing Of Developmental Stress And Phenotypic Plasticity: Effects Of Nutritional Stress At Different Developmental Periods On Physiological And Cognitive-Behavioral Traits In The Zebra Finch (Taeniopygia Guttata), Buddhamas Kriengwatana

Electronic Thesis and Dissertation Repository

Developmentally plastic organisms can respond to stressful environmental conditions by altering multiple aspects of their phenotype, often in a permanent fashion. The timing of developmental stress influences these phenotypic alterations because the prioritization of resources to traits necessary to overcome the stressor may be costly for the development of other traits. Despite the importance of this timing, few studies in birds have accounted for it, and those that have usually examined the effect on a single or few variables. This dissertation addresses the outstanding issues regarding i) the effects of timing of developmental stress on developmental plasticity, and ii) the …

The Influence Of Proficiency And Age Of Acquisition On Second Language Processing: An Fmri Study Of Mandarin-English Bilinguals, Emily S. Nichols

Electronic Thesis and Dissertation Repository

Research investigating the neural correlates of second language (L2) processing has usually studied age of acquisition (AoA) and proficiency separately. Presently, we examined both in parallel, treated as continuous variables. We used fMRI to study neural activity for L2 processing in adult native Mandarin speakers who are L2 English speakers. Behavioral measures of language proficiency and AoA were obtained from subjects prior to performing a picture-word matching task during an fMRI scan. Brain activity during L2 English processing was shown to be independently affected by AoA and proficiency; activity in left superior temporal gyrus and right parahippocampal gyrus was modulated …

Exploring Parental Experiences And Decision-Making Processes Following A Fetal Anomaly Diagnosis, Ramona L. Fernandez

Electronic Thesis and Dissertation Repository

Often the first indication that something may be wrong in a seemingly normal pregnancy occurs during the first detailed ultrasound appointment between 16 and 20 weeks gestation. Even the most tentative suspicions of fetal anomalies is jarring. Parent’s default reality of a normal pregnancy and a ‘perfect child’ changes to one of risk factors and the possibility of an ‘unhealthy child’. This study begins with the realization of this first loss in a series of losses that follow for parents as they grapple with diagnostic information to be able to make informed medical decisions regarding their fetus and pregnancy. The …

Exploring The Neural Basis Of Top-Down Guided Action In Macaque Monkeys, Jessica M. Phillips

Electronic Thesis and Dissertation Repository

To thoroughly characterize any brain mechanism requires an appropriate animal model for invasive studies. An invaluable model system used toward a comprehension of cognitive neurophysiology is the macaque monkey. It is important to delineate similarities and limitations for this model in relation to the human brain and cognition. In this thesis, we have thus conducted three experiments to investigate putative generalizations between monkeys and humans regarding the neural processes associated with top-down action control in monkeys.

Our daily behaviour is largely comprised of automatic routine actions. The frequent repetition of certain behaviours in response to particular contexts can give rise …

Fmri Reveals The Neural Correlates Of Real And Pantomimed Tool Use In Humans, Joseph Umberto Paciocco

Electronic Thesis and Dissertation Repository

Although functional magnetic resonance imaging (fMRI) can be used to study the neural mechanisms underlying greatly expanded cognitive functions in humans like tool use, surprisingly little fMRI research has been done on actual tool use. In fact, due to technical constraints, most fMRI studies have used pantomimed actions as a proxy for real use. However, human neuropsychology patients who are impaired at pantomiming often improve when handling a tool suggesting potential neural differences. We used fMRI to record brain activation while 13 right-handed participants performed one of two tasks, real or pantomime tool use with one of two tools, a …

Examining The Relationships Between Imagery, Sport Motivation, And Athletic Identity In Curling, Nicole Westlund

Electronic Thesis and Dissertation Repository

Imagery use, motivation, and athletic identity all have been investigated in sport; however, a study examining the relationships among these three constructs has yet to be conducted. The participants (N = 213) were club and competitive curlers (M_age = 49.0; SD = 15.39). Results showed that athletic identity was significantly correlated with all five imagery functions and six behavioural regulations (p < .01) except for external regulation and amotivation. Multiple regression analyses predicting imagery use from both the behavioural regulations and athletic identity were conducted for each imagery function in club and competitive curlers. Athletic identity, identified regulation, and integrated regulation emerged as significant predictors of imagery use (p < .05). These findings suggest that there is a link between imagery use, motivation, and athletic identity. Researchers and sport psychologists can use these findings to develop more effective psychological skills training programs to improve the performance of curlers.

Dissociable And Dynamic Components Of Cognitive Control: A Developmental Electrophysiological Investigation, Matthew Waxer

Electronic Thesis and Dissertation Repository

One standard task used to investigate the development of cognitive control is the Dimensional Change Card Sort (DCCS). Performance and patterns of brain activity associated with the DCCS show continued age-related advances into early adolescence. According to many theoretical accounts, the DCCS places demands on a single underlying executive control process. Three experiments examined the possibility that the DCCS places demands on multiple control processes that follow distinct developmental trajectories. In Experiment 1, rule switching and conflict processing made orthogonal contributions to DCCS performance. Rule switching was associated with a cue-locked late frontal negativity (LFN) event-related potential (ERP) and conflict …

Mental Blocks: The Behavioural Effects And Neural Encoding Of Obstacles When Reaching And Grasping, Craig S. Chapman

Electronic Thesis and Dissertation Repository

The ability to adeptly interact with a cluttered and dynamic world requires that the brain simultaneously encode multiple objects. Theoretical frameworks of selective visuomotor attention provide evidence for parallel encoding (Baldauf & Deubel, 2010; Cisek & Kalaska, 2010; Duncan, 2006) where concurrent object processing results in neural competition. Since the end goal of object representation is usually action, these frameworks argue that the competitive activity is best characterized as the development of visuomotor biases. While some behavioural and neural evidence has been accumulated in favour of this explanation, one of the most striking, yet deceptively common, demonstrations of this capacity …

Seasonal Hippocampal Plasticity In Food-Storing Birds., David F Sherry, Jennifer S Hoshooley

Psychology Publications

Both food-storing behaviour and the hippocampus change annually in food-storing birds. Food storing increases substantially in autumn and winter in chickadees and tits, jays and nutcrackers and nuthatches. The total size of the chickadee hippocampus increases in autumn and winter as does the rate of hippocampal neurogenesis. The hippocampus is necessary for accurate cache retrieval in food-storing birds and is much larger in food-storing birds than in non-storing passerines. It therefore seems probable that seasonal change in caching and seasonal change in the hippocampus are causally related. The peak in recruitment of new neurons into the hippocampus occurs before birds …