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dc.contributor.authorMilstein, David
dc.contributor.otherQueen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.))en
dc.date2013-06-25 16:55:24.481en
dc.date2013-06-25 17:18:25.393en
dc.date.accessioned2013-06-26T15:23:00Z
dc.date.available2013-06-26T15:23:00Z
dc.date.issued2013-06-26
dc.identifier.urihttp://hdl.handle.net/1974/8090
dc.descriptionThesis (Ph.D, Neuroscience Studies) -- Queen's University, 2013-06-25 17:18:25.393en
dc.description.abstractDeal or no deal? Hold ‘em or fold ‘em? Buy, hold or sell? When faced with uncertainty, a wise decision-maker evaluates each option and chooses the one they deem most valuable. Scientists studying decision making processes have spent much theoretical and experimental effort formalizing a framework that captures how decision makers can maximize the amount of subjective value they accrue from such decisions. This thesis tested two hypotheses. The first was that subjective value guides our simplest and most common of motor actions similar to how it guides more deliberative economic decisions. The second was that subjective value is allocated across pre-motor regions of the brain to make our actions more efficient. To accomplish these goals, I adapted a paradigm used by behavioural economists for use in neurophysiological experiments in non-human primates. In our task, monkeys repeatedly make quick, orienting eye movements, known as saccades, to targets, which they learned through experience, had different values. In support of the hypothesis that subjective value influences simple motor actions, the speed with which monkeys responded, known as saccadic reaction time (SRT), and their saccadic choices to valued targets were highly correlated and therefore both acted as a behavioural measures of subjective value. Two complimentary results support the hypothesis that subjective value influences activity in the intermediate layers of the superior colliculus (SCi) – a well-studied brain region important to the planning and execution of saccades - to produce efficient actions. First, when saccades were elicited with microstimulation, we found that the timing and spatial allocation of pre-saccadic activity in the SC was shaped by subjective value. Second, the baseline preparatory activity and transient visual activity of SCi neurons prior to saccade generation was also influenced by subjective value. Our results can be incorporated into existing models of SC functioning that use dynamic neural field theory. I suggest that saccades of higher subjective value will result in higher activation of their associated neural field such that they will be more likely and more quickly selected. In summary, this thesis demonstrates that subjective value influences neural mechanisms, not only for deliberative decision making, but also for the efficient selection of simple motor actions.en_US
dc.languageenen
dc.language.isoenen_US
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectExpected Valueen_US
dc.subjectSuperior Colliculusen_US
dc.subjectMicrostimulationen_US
dc.subjectSingle Cell Recordingen_US
dc.subjectSaccadic Reaction Timesen_US
dc.subjectProbabilityen_US
dc.subjectNeuroeconomicsen_US
dc.subjectRewarden_US
dc.titleThe Influence of Relative Subjective Value on Preparatory Activity in the Superior Colliculus as Indexed by Saccadic Reaction Timesen_US
dc.typethesisen_US
dc.description.degreePh.Den
dc.contributor.supervisorDorris, Michael C.en
dc.contributor.departmentNeuroscience Studiesen


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