The Contribution of Cortical Feature Processing to Oculomotor Target Selection

Simple item page
dc.contributor.advisorMurray, Richard
dc.contributor.advisorFallah, Mazyar
dc.contributor.authorKehoe, Devin William Heinze
dc.date.accessioned2024-03-18T18:01:47Z
dc.date.available2024-03-18T18:01:47Z
dc.date.issued2024-03-16
dc.date.updated2024-03-16T10:45:06Z
dc.degree.disciplinePsychology (Functional Area: Brain, Behaviour & Cognitive Science)
dc.degree.levelDoctoral
dc.degree.namePhD - Doctor of Philosophy
dc.description.abstractWe effortlessly move our eyes to objects with specific features and avoid objects with other features. This feature-guided target selection behavior has been studied extensively in experimental psychology and systems neuroscience. By now, the visual and cognitive factors that mediate target selection and the neural signatures of target selection in oculomotor substrates are clear. For example, neural activation encoding targets and distractors gradually divergences over time therefore signalling stimulus identity, while visual/cognitive factors like bottom-up salience or top-down priority modulate the precise time of this divergence. But despite the extensive research on oculomotor target selection, little research has examined how neural activation in oculomotor substrates encoding potential eye movements vectors is reweighted to indicate stimulus identity. Meanwhile, a parallel branch of systems neuroscience has thoroughly examined the function and anatomy of the visual processing pipeline distributed throughout the neocortex of mammals. Heretofore, however, there has been little if any attempt to characterize the relationship between cortical visual feature processing and oculomotor vector encoding during feature-guided target selection. This dissertation presents a series of behavioral experiments that provide several insights into this relationship. In these experiments, I measure the perturbation of target-directed saccades elicited by competitive remote distractors as a function of (1) the feature-space distance between targets and distractors and/or (2) distractor processing time. Given the close correspondence between saccade perturbation metrics and the underlying physiology of the oculomotor system, this methodology offers a non-invasive analog to examining the time course of oculomotor distractor activation during feature-guided target selection. In one set of experiments, I observed that distractor activation encodes the feature-space distance between targets and distractors in a manner consistent with attentional pruning of visual features observed in cortical feature representations during feature-based attentional deployment. In another set of experiments, I observed that the pattern of visual onset response latencies across distractor features mimics the pattern robustly observed between the cortical modules specialized for processing the respective features. These results indicate a close representational and temporal parity between feature encoding in oculomotor and (cortical) perceptual systems. I therefore propose a broad theory of oculomotor feature encoding whereby eye movement vectors in oculomotor substrates are dynamically and continuously reweighted by the feature-dependent network of cortical modules in the perceptual system necessary for representing the relevant feature set of the potential eye movement target.
dc.identifier.urihttps://hdl.handle.net/10315/41897
dc.languageen
dc.rightsAuthor owns copyright, except where explicitly noted. Please contact the author directly with licensing requests.
dc.subjectNeurosciences
dc.subjectExperimental psychology
dc.subjectBehavioral sciences
dc.subject.keywordsEye movements
dc.subject.keywordsSaccades
dc.subject.keywordsTarget selection
dc.subject.keywordsFeatures
dc.subject.keywordsBehavioral chronometry
dc.subject.keywordsSensorimotor integration
dc.subject.keywordsSaccade curvature
dc.titleThe Contribution of Cortical Feature Processing to Oculomotor Target Selection
dc.typeElectronic Thesis or Dissertation

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
HeinzeKehoe_Devin_W_2023_Phd.pdf
Size:
6.04 MB
Format:
Adobe Portable Document Format
Download
License bundle
Now showing 1 - 2 of 2
No Thumbnail Available
Name:
license.txt
Size:
1.87 KB
Format:
Plain Text
Description:
Download
No Thumbnail Available
Name:
YorkU_ETDlicense.txt
Size:
3.39 KB
Format:
Plain Text
Description:
Download

Collections

Psychology (Functional Area: Brain, Behaviour & Cognitive Science)

All items in the YorkSpace institutional repository are protected by copyright, with all rights reserved except where explicitly noted.