Contribution of the monkey frontal eye field to covert visual attention.
The frontal eye field (FEF) has long been regarded as a cortical area critically involved in the execution of voluntary saccadic eye movements. However, recent studies have suggested that the FEF may also play a role in orienting attention. To address this issue, we reversibly inactivated the FEF using multiple microinjections of muscimol, a GABAA agonist, in two macaque monkeys performing visually guided saccades to a single target. The effects of FEF inactivation were also studied in a covert visual search task that required monkeys to search for a target presented among several distractors without making any eye movements. As expected, inactivating the FEF caused spatially selective deficits in executing visually guided saccades, but it also altered the ability to detect a visual target presented among distractors when no eye movements were permitted. These results allow us to conclude definitively to an involvement of the FEF in both oculomotor and attentional functions. Comparison of the present results with a similar experiment conducted in the lateral intraparietal cortex area revealed qualitatively different deficits, suggesting that the two areas may make distinct contributions to selective attention processes.
Wardak
Claire
C
Institut des Sciences Cognitives, Unité Mixte de Recherche 5015, Centre National de la Recherche Scientifique-Université Claude Bernard Lyon I, 69675 Bron, France.
Ibos
Guilhem
G
Duhamel
Jean-René
JR
Olivier
Etienne
E
D000818:Animals; D001288:Attention / Q000502:physiology*; D008252:Macaca fascicularis; D008253:Macaca mulatta; D010775:Photic Stimulation / Q000379:methods; D012438:Saccades / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*