Visuomotor robustness is based on integration not segregation

How can we explain, that DF – a patient with a damaged ventral stream – can act normally in many everyday tasks despite her profound perceptual disability. The classical answer is that perception and action are based on separate visual streams. Here, I will explain why this view is problematic and offer an alternative answer. Specifically, I will argue that the preserved performance of DF should be seen as evidence of the redundancy of visuomotor control and not as evidence of a segregation between vision for perception and action.

Research highlights► The motor system has access to a redundant set of visual information. ► Redundancy within the visuomotor system can explain visuomotor robustness after damage to the visual system. ► Neuropsychological evidence of spared visuomotor capacity after ventral stream damage is not sufficient to support the claim of separate visual pathways for perception and action. ► Redundancy means that spared capacity after brain damage is hard to interpret. ► Visuomotor deficits can tell us more about the ventral stream’s contribution to action than preserved actions.