Primary visual cortex and visual awareness.

The primary visual cortex (V1) is probably the best characterized area of primate cortex, but whether this region contributes directly to conscious visual experience is controversial. Early neurophysiological and neuroimaging studies found that visual awareness was best correlated with neural activity in extrastriate visual areas, but recent studies have found similarly powerful effects in V1. Lesion and inactivation studies have provided further evidence that V1 might be necessary for conscious perception. Whereas hierarchical models propose that damage to V1 simply disrupts the flow of information to extrastriate areas that are crucial for awareness, interactive models propose that recurrent connections between V1 and higher areas form functional circuits that support awareness. Further investigation into V1 and its interactions with higher areas might uncover fundamental aspects of the neural basis of visual awareness.