Transcranial magnetic stimulation of the human frontal eye field facilitates visual awareness.
What are the brain mechanisms allowing a stimulus to enter our awareness? Some theories suggest that this process engages resources overlapping with those required for action control, but experimental support for these ideas is still required. Here, we investigated whether the human frontal eye field (FEF), an area known to control eye movements, is involved in visual awareness. Volunteers participated in a backward masking task in which they were able to detect a target in a small proportion of trials. We observed that a single pulse of transcranial magnetic stimulation applied over the FEF shortly before the target's onset facilitated visual sensitivity; subjects were able to detect an otherwise subliminal object. These results show that modulating the neuronal activity of the FEF can enhance visual detection, thereby yielding new insights into the neural basis of visual awareness.
Grosbras
Marie-Hélène
MH
Cognitive Neuroscience Unit, Montreal Neurological Institute, 3801 University, Montréal, QC, Canada H3A2B4. marieg@bic.mni.mcgill.ca
Paus
Tomás
T
D000328:Adult; D001364:Awareness / Q000502:physiology / Q000528:radiation effects*; D001931:Brain Mapping; D004292:Dominance, Cerebral; D004558:Electric Stimulation / Q000379:methods*; D005123:Eye / Q000528:radiation effects*; D005133:Eye Movements / Q000502:physiology; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010775:Photic Stimulation; D011930:Reaction Time; D050781:Transcranial Magnetic Stimulation; D014793:Visual Cortex / Q000033:anatomy & histology / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology / Q000528:radiation effects*