Peripheral oculomotor palsy affects orienting of visuospatial attention.

Patients affected by VI cranial nerve palsy were required to orient their attention in monocular vision and to detect a stimulus appearing either in attended or in unattended locations. Results showed that while during non-paretic eye vision stimulus detection in the attended location was faster than that in the unattended one, during paretic eye vision no difference in detection speed was present. However, in this latter condition, detection speed in both attended and un attended locations were as fast as that measured during non-paretic eye vision in attended location. Demonstration that peripheral oculomotor impairment influences monocular covert orienting of visuospatial attention strongly support the idea that visuospatial attention and oculomotor mechanisms share similar cortical networks.