Cognitive Lunch Abstract for February 18

The next Cognitive Lunch will be held Wednesday, February 18.
Time: 12:10-1:10 p.m.
Place: Psychology Conference Room (Room 128)

"Unconfounding Stimulus - and Response - Related Processes and Determining Sensory-Motor Locus in Neural Recordings" will be presented by Jun Zhang, Department of Psychology, University of Michigan, Ann Arbor.

Abstract:
When a neural signal (single neuron activity, ERP waveform, fMRI activation, etc) is being recorded simultaneously as the animal/human subject performs a behavioral task, a question arises as to whether the recorded neural signal reflects encoding/analysis of the stimulus, preparation/execution of the response, or the "decision" that translates a stimulus into a response. I will present several techniques that allow us to 1) unambiguously determine the "locus" along sensory-motor arc of the recorded neural activity based on their trial-by-trial correlation with behavior; 2) uniquely recover a stimulus-locked and a response-locked component in the recorded neural activity based on trial-by-trial variability in response time (RT). Applying 1) to single neuron recording data allows a refined analysis and characterization of LIP accumulation neurons in a random-dot motion discrimination task. Applying 2) to ERP data clarifies a long-standing debate in ERP literature concerning the so-called "P3 anteriorization" phenomenon for Go/Nogo tasks.