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Perception Meets Action: Fmri And Behavioural Investigations Of Human Tool Use, Kenneth F. Valyear

Electronic Thesis and Dissertation Repository

Tool use is essential and culturally universal to human life, common to hunter-gatherer and modern advanced societies alike. Although the neuroscience of simpler visuomotor behaviors like reaching and grasping have been studied extensively, relatively little is known about the brain mechanisms underlying learned tool use.

With learned tool use, stored knowledge of object function and use supervene requirements for action programming based on physical object properties. Contemporary models of tool use based primarily on evidence from the study of brain damaged individuals implicate a set of specialized brain areas underlying the planning and control of learned actions with objects, distinct …

Regulation Of Akt And Wnt Signalling By The Dopamine D2 Receptor And Metabotropic Glutamate Receptor 2/3, Laurie P. Sutton

Electronic Thesis and Dissertation Repository

Akt and the Wnt pathway, two cascades that regulate GSK-3, have been implicated in schizophrenia and antipsychotic drug action. Although it is known that antipsychotic drugs alleviate psychosis by blocking the dopamine D2 receptor (D2DR) and that metabotropic glutamate receptor 2/3 (mGluR2/3) agonists may improve some of the symptoms of schizophrenia, it is unclear if both classes of drugs exert their effects through Akt, GSK-3 and/or the Wnt pathway or if changes in these pathways are mediated through the D2DR and mGluR2/3 respectively. In addition to antipsychotics, mood stabilizers and antidepressants also target GSK-3, suggesting that there must be something …

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 …