Contextual effects on visual perception

Abstract

In this thesis we improve our understanding of how contextual effects affect the activity of neurons in primary visual cortex (V1). We investigate a variety of contextual effects, starting with the position of visual stimuli on the retina. We then look at the neural traces of iconic memory in V1, and how those can be affected by adding the context of a cue. We then show that mice can perceive figures that are defined by texture patterns, and that the context of being part of a figure elicits enhanced V1 responses to identical visual stimulation. We further suggest that the contextual modulation is driven by interneurons in the cortex that modulate the responses of cells around them. Last, we investigate the effects of task-related context on visual perception in the mouse and in humans. We present further evidence that V1 is much more than a simple relay station of neural signals but encodes different forms of contextual information