Probabilistic decision making by slow reverberation in cortical circuits.
Recent physiological studies of alert primates have revealed cortical neural correlates of key steps in a perceptual decision-making process. To elucidate synaptic mechanisms of decision making, I investigated a biophysically realistic cortical network model for a visual discrimination experiment. In the model, slow recurrent excitation and feedback inhibition produce attractor dynamics that amplify the difference between conflicting inputs and generates a binary choice. The model is shown to account for salient characteristics of the observed decision-correlated neural activity, as well as the animal's psychometric function and reaction times. These results suggest that recurrent excitation mediated by NMDA receptors provides a candidate cellular mechanism for the slow time integration of sensory stimuli and the formation of categorical choices in a decision-making neocortical network.
Wang
Xiao-Jing
XJ
Volen Center for Complex Systems, Brandeis University, Waltham, MA 02254, USA. xjwang@brandeis.edu
D000818:Animals; D002540:Cerebral Cortex / Q000166:cytology / Q000502:physiology*; D003657:Decision Making / Q000502:physiology*; D008433:Mathematics; D008959:Models, Neurological; D016571:Neural Networks, Computer; D009474:Neurons / Q000378:metabolism; D011930:Reaction Time; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013569:Synapses / Q000378:metabolism
D016194:Receptors, N-Methyl-D-Aspartate