Graduation Year

2016

Date of Submission

4-2016

Document Type

Campus Only Senior Thesis

Degree Name

Bachelor of Arts

Department

Neuroscience

Second Department

W.M. Keck Science Department

Reader 1

Catherine L. Reed

Reader 2

Thomas Borowski

Terms of Use & License Information

Terms of Use for work posted in Scholarship@Claremont.

Rights Information

© 2016 Daivik B Vyas

Abstract

Attention uses sensory inputs and goals to select information from our environment. Monkey electrophysiological literature demonstrates that visuo-tactile bimodal neurons (respond to visual and tactile stimuli presented on/near the hand) facilitate multisensory integration. Human behavioral studies show that hand position/function bias visual attention. Event-related potentials (ERPs) reveal the cortical dynamics coordinating visual inputs, body position, and action goals. Early, sensory ERPs (N1) indicate multisensory integration. Later, cognitive ERPs (P3) reflect task-related processing. Study 1 investigates a discrepancy between monkey and human literatures. Monkey studies demonstrate bimodal neuron responses equidistantly around the whole hand, but human studies demonstrate attentional bias for grasping space. In a visual detection paradigm, participants positioned their hand so target and non-target stimuli appeared near the palm or back of the hand; ERPs were measured. N1 components indicated no amplitude differences between Palm vs. Back conditions, but P3 components revealed greater target vs. non-target differentiation for Palm conditions. Results suggest cortical timing underlies grasping vs. whole hand bias differences: early processing does not differentiate using hand function, but cognitive processing does when stimuli are discriminated for action. Study 2 investigates whether proprioceptive inputs facilitate visual processing. In a visual detection paradigm, participants viewed stimuli presented between occluders blocking view of a hand positioned either near or far from the stimuli. N1 amplitudes were similar for near and far conditions, but P3 amplitudes for target/non-target differences were accentuated for near conditions. Proprioceptive effects emerge later in processing. ERP reveals the cortical dynamics underlying hand position effects on vision.

Comments

Best Senior Thesis in Neuroscience

Available for download on Tuesday, May 15, 2018

This thesis is restricted to the Claremont Colleges current faculty, students, and staff. It is not available for interlibrary loan. Please send a request for access through Contact Us.

Share

COinS