Stochastic resonance in visual cortical neurons: does the eye-tremor actually improve visual acuity?

We demonstrate with electrophysiological recordings that visual cortical cell responses to moving stimuli with very small amplitudes can be enhanced by adding a small amount of noise to the motion pattern of the stimulus. This situation mimics the micro-movements of the eye during fixation and shows that these movements could enhance the performance of the cells. In a biophysically realistic model we show in addition, that micro-movements can be used to enhance the visual resolution of the cortical cells by means of spatiotemporal integration. This mechanism could partly underlie the hyperacuity properties of the visual system.