Center for Neural Circuits and Behavior, Neurobiology Section, University of California, San Diego, San Diego, United States; Department of Neuroscience, University of California, San Diego, San Diego, United States; Department of Physiology, University of California, San Francisco, San Francisco, United States
Sarah Ruediger
Center for Neural Circuits and Behavior, Neurobiology Section, University of California, San Diego, San Diego, United States; Department of Neuroscience, University of California, San Diego, San Diego, United States; Department of Physiology, University of California, San Francisco, San Francisco, United States
Shawn R Olsen
Center for Neural Circuits and Behavior, Neurobiology Section, University of California, San Diego, San Diego, United States; Department of Neuroscience, University of California, San Diego, San Diego, United States; Allen Institute for Brain Science, Seattle, United States
Center for Neural Circuits and Behavior, Neurobiology Section, University of California, San Diego, San Diego, United States; Department of Neuroscience, University of California, San Diego, San Diego, United States; Department of Physiology, University of California, San Francisco, San Francisco, United States; Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
Visually guided perceptual decisions involve the sequential activation of a hierarchy of cortical areas. It has been hypothesized that a brief time window of activity in each area is sufficient to enable the decision but direct measurements of this time window are lacking. To address this question, we develop a visual discrimination task in mice that depends on visual cortex and in which we precisely control the time window of visual cortical activity as the animal performs the task at different levels of difficulty. We show that threshold duration of activity in visual cortex enabling perceptual discrimination is between 40 and 80 milliseconds. During this time window the vast majority of neurons discriminating the stimulus fire one or no spikes and less than 16% fire more than two. This result establishes that the firing of the first visually evoked spikes in visual cortex is sufficient to enable a perceptual decision.
