RT Journal Article SR Electronic T1 Simulating Cortical Feedback Modulation as Changes in Excitation and Inhibition in a Cortical Circuit Model JF eneuro JO eneuro FD Society for Neuroscience SP ENEURO.0208-16.2016 DO 10.1523/ENEURO.0208-16.2016 VO 3 IS 4 A1 Edward Zagha A1 John D. Murray A1 David A. McCormick YR 2016 UL http://www.eneuro.org/content/3/4/ENEURO.0208-16.2016.abstract AB Cortical feedback pathways are hypothesized to distribute context-dependent signals during flexible behavior. Recent experimental work has attempted to understand the mechanisms by which cortical feedback inputs modulate their target regions. Within the mouse whisker sensorimotor system, cortical feedback stimulation modulates spontaneous activity and sensory responsiveness, leading to enhanced sensory representations. However, the cellular mechanisms underlying these effects are currently unknown. In this study we use a simplified neural circuit model, which includes two recurrent excitatory populations and global inhibition, to simulate cortical modulation. First, we demonstrate how changes in the strengths of excitation and inhibition alter the input–output processing responses of our model. Second, we compare these responses with experimental findings from cortical feedback stimulation. Our analyses predict that enhanced inhibition underlies the changes in spontaneous and sensory evoked activity observed experimentally. More generally, these analyses provide a framework for relating cellular and synaptic properties to emergent circuit function and dynamic modulation.