PRESERVED GRIP SCALING TO UNSEEN OBJECTS FOLLOWING A UNILATERAL LESION TO V1 FOR IMMEDIATE BUT NOT DELAYED GRASPING

Patients with damage to V1 can sometimes direct actions towards ‘unseen’ targets located in areas of the visual field that are deemed ‘blind’ on the basis of static perimetry tests. Here, we show that a patient with a complete right homonymous hemianopia after a V1 lesion remains sensitive to the width of objects presented in her blind field but only when reaching out to grasp them in ‘real-time’. A subsequent fMRI experiment indicated that these preserved abilities are likely mediated by spared extra-geniculostriate pathways, while a small “tag” of occipital cortex located at the occipital pole remained unresponsive. Taken together, the results support the view that visually guided movements can be mediated by pathways that do not support visual consciousness.

Name thesis:degree_name

M Sc

Discipline thesis:degree_discipline

Neuroscience

Year dc:date.issued

2010

Author dc:creator

• Whitwell, Robert Leslie

Advisors dc:contributor.advisor

• Goodale, Melvyn
• Brown, Patrick
• Everling, Stefan

• dorsal stream
• grasping
• V1
• blindsight
• perception-action

Handle dc:identifier.uri

https://hdl.handle.net/20.500.14721/19463

OAI identifier oai:identifier

oai:uwo.scholaris.ca:20.500.14721/19463