Visual Information Processing in Cortex and a Potential Link to Brain Disorders

Abstract

In visual cortex principal cells, the pyramidal neurons, can activate inhibitory interneurons that in turn control the visual response gain of other pyramidal neurons via suppression of visual responses. By employing optogenetic stimulation we show that both pyramidal and interneuron stimulation reduces receptive field (RF) area and increases signal-to-noise ratio (SNR) for such visual responses. We also show that such an increase in SNR increases information about visual stimuli that is encoded by action potentials. Since all sensory inputs will activate pyramidal neurons, it is concluded that any activation of visual cortex, be due to sensory inputs or state of wakefulness may enhance visual information processing. Since inhibitory neuron function is affected in brain injury and several brain disorders, these results may help to better understand the pathogenesis of brain dysfunction.