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Simons Lab

wpe2.jpg (12510 bytes) Our laboratory investigates neuronal integration within identified, small networks of neurons that process sensory information from the large facial vibrissae, or whiskers, in rats.  The primary focus is the primary somatosensory cortex. There, identified clusters of layer IV neurons, called "barrels," are related in one-to-one fashion with their corresponding whiskers. Barrels are local circuits that perform an initial transformation of incoming signals from the somatosensory thalamus. The transformed signals are then propagated to other layers of the cortical column. Computer-controlled whisker stimuli and single cell recording techniques are used to examine how information is integrated by cortical neurons. Recordings also are obtained from animals trained to perform tactile discriminations using their whiskers.

Neurophysiological findings are incorporated into computer models that simulate known synaptic connections among cortical neurons and the thalamic cells that are presynaptic to them. The model networks are activated by pre-recorded spike trains from thalamocortical relay cells, and the output of the model neurons is compared quantitatively with that obtained in real barrels. Dynamical systems analysis is used to characterize the operations of the circuits. Similar approaches are used to understand how thalamic circuitry processes whisker-evoked activity from the brainstem and, in turn, how brainstem circuits transform incoming activity from the whiskers themselves.

How does a barrel "work"?

Check out BARRELS at http://simonslab.neurobio.pitt.edu/barrels

Here are studies by students in (or recently departed from) the lab:

Randy Bruno (Ph.D. student, Program in Neurobiology) Feedforward Inhibition in Thalamocortical Circuits
Kathy Kelly (Ph.D. student, Physical Therapy) Responses of Thalamic and Cortical Neurons During Active Touch
Vivek Khatri (Ph.D. student, CNUP) Functional Organization of Sub-Networks Within Individual Cortical Barrels
SooHyun Lee (Ph.D. student, CNUP) Modulation of the Ascending Somatosensory System by Primary Motor Cortex
Brad Minnery (Ph.D. student, Program in Neurobiology) Trigeminothalamic Response Transformations
Mish Shoykhet (MD/Ph.D. student) Functional Development of Thalamocortical Circuits
Simona Temereanca (Ph.D student, Program in Neurobiology) Corticothalamic Modulation of Stimulus-Evoked Thalamic Responses
Tom Prigg (Research Assistant, B.S., University of Pittsburgh) Thalamic Activity During Spatial Discrimination Behavior
Pranav Shetty (B.S. graduate, Dept. of Neuroscience; currently a Pitt Med freshman) Responses of Primary Afferent Neurons at the Age of Whisking Onset

This page was last updated on 04/12/07