Fig. 2.

Computational modeling results and experimental predictions. A. In the cortical circuit model of spatial WM, a brief stimulus excites a subset of neurons, which encode the stimulus across the delay through a pattern of persistent activity that is shaped by recurrent excitation and lateral inhibition. Disinhibition is implemented via reduction of NMDAR conductance from pyramidal cells onto inhibitory interneurons (G_EI) (Murray et al., 2014). Disinhibition results in a broadened WM representation. B. The variability of WM report increases with delay duration. Disinhibition increases the rate at which variability increases, constituting a deficit in WM maintenance. C. Distractors are modeled as an intervening stimulus inputs during the delay. Under the control condition, there is no overlap between distractor and WM representations, and the report is unperturbed by the distractor. Under disinhibition, there is overlap and the report is shifted toward the distractor location. D. The mean WM report is shifted in the direction of the distractor, with dependence on the angular separation between distractor and cue. Disinhibition shows a larger distractibility window, i.e. the separation with maximal impact on WM report. E. The distractibility window and WM variability (chosen here at 3-s delay, no-distractor condition) are correlated as both smoothly increase with the strength of disinhibition (reduction of G_EI). Panels A-D adapted from (Murray et al., 2014) with permission.