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The Impact or Recent Visual Experience on Neural Activity and Perception

Stan, Patricia L. (2023) The Impact or Recent Visual Experience on Neural Activity and Perception. Doctoral Dissertation, University of Pittsburgh. (Unpublished)

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Recent visual experience heavily influences our visual perception, helping to constrain possible interpretations of the vast amount of visual input found in the world. How does recent visual experience influence the activity of cortical neurons to allow for improved performance on a perceptual discrimination task? In this dissertation, we used recent visual experience to create different task contexts that allowed us to probe how neural responses to an identical visual input are modulated by different cognitive factors. We recorded from populations of neurons in visual area V4 while rhesus macaques performed a natural image change detection task under various task conditions. In one study, we modulated the expectation of the incoming visual input. We found that higher expectation led to improved ability to detect a change in an image. This improvement was associated with decreased neural responses to the image, indicating that a reduction in activity can improve stimulus encoding. Additionally, higher expectation was associated with an enhancement of short-timescale adaptation, suggesting that adaptation can be modulated by other cognitive factors. Finally, expectation was associated with decreased trial-to-trial shared variability, indicating that shared fluctuations are reduced and less likely to impact stimulus coding. In a second study, we modulated the way in which an image could change, leading to differences in task difficulty. We found that improved behavioral performance due to task difficulty was likewise associated with decreases in neural activity and shared variability. Overall, in both studies we successfully created different task contexts that resulted in improvements in the ability to detect a change in an image. These improvements were associated with changes in neuronal firing rates and population-level interactions. Strikingly, despite the different experimental modulation used in each study, we found the same set of neural effects coinciding with higher behavioral performance. Together, our studies contribute to the understanding of the underlying changes in neural activity that can benefit perception.


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Item Type: University of Pittsburgh ETD
Status: Unpublished
CreatorsEmailPitt UsernameORCID
Stan, Patricia L.pls23@pitt.edupls23
ETD Committee:
TitleMemberEmail AddressPitt UsernameORCID
Committee ChairRunyan,
Committee MemberCohen,
Committee MemberOlson,
Committee MemberYu,
Committee MemberKohn,
Committee MemberMatthew,
Date: 26 January 2023
Date Type: Publication
Defense Date: 4 November 2022
Approval Date: 26 January 2023
Submission Date: 8 December 2022
Access Restriction: 2 year -- Restrict access to University of Pittsburgh for a period of 2 years.
Number of Pages: 176
Institution: University of Pittsburgh
Schools and Programs: Dietrich School of Arts and Sciences > Neuroscience
Degree: PhD - Doctor of Philosophy
Thesis Type: Doctoral Dissertation
Refereed: Yes
Uncontrolled Keywords: Neuroscience, neural activity, visual cortex, visual perception, expectation
Date Deposited: 26 Jan 2023 15:07
Last Modified: 26 Jan 2023 15:07


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