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dc.contributor.advisor Fitzpatrick, David en_US
dc.contributor.author Wu, Wei en_US
dc.date.accessioned 2009-05-01T18:31:41Z
dc.date.available 2011-07-26T04:30:03Z
dc.date.issued 2009 en_US
dc.identifier.uri http://hdl.handle.net/10161/1152
dc.description Dissertation en_US
dc.description.abstract <p>The visual system is thought to represent the trajectory of moving objects in the activity of large populations of cortical neurons that respond preferentially to the direction of stimulus motion. Here I employed in vivo voltage sensitive dye (VSD) imaging to explore how abrupt changes in the trajectory of a moving stimulus impact the population coding of motion direction in ferret primary visual cortex (V1). For motion in a constant direction, the peak of the cortical population response reliably signaled the stimulus trajectory; but for abrupt changes in motion direction, the peak of the population response departed significantly from the stimulus trajectory in a fashion that depended on the size of the direction deviation. For small direction deviation angles, the peak of the active population shifted from values consistent with the initial direction of motion to those consistent with the final direction of motion by progressing smoothly through intermediate directions not present in the stimulus. In contrast, for large direction deviation angles, peak values consistent with the initial motion direction were followed by: a small deviation away from the final motion direction, a rapid 180° jump, and a gradual shift to the final direction. These departures of the population response from the actual trajectory of the stimulus predict specific misperceptions of motion direction that were confirmed by human psychophysical experiments. I conclude that cortical dynamics and population coding mechanisms combine to place constraints on the accuracy with which abrupt changes in direction of motion can be represented by cortical circuits.</p> en_US
dc.format.extent 3475782 bytes
dc.format.mimetype application/pdf
dc.language.iso en_US
dc.subject Biology, Neuroscience en_US
dc.subject Psychology, Cognitive en_US
dc.subject direction en_US
dc.subject dynamic en_US
dc.subject population coding en_US
dc.subject visual cortex en_US
dc.subject voltage sensitive dye en_US
dc.title Distortions in Perceived Direction of Motion Predicted by Population Response in Visual Cortex en_US
dc.type Dissertation en_US
dc.department Neurobiology en_US
duke.embargo.months 24 en_US

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