Neural correlates of saccade planning in infants: a high-density ERP study.
Neural correlates of saccade planning in 6-month-old infants were investigated by high-density event-related potentials. Subjects made saccades to a target stimulus following a time gap from fixation stimulus offset (gap trials) or with the fixation stimulus still present (overlap trials). Like adults, infants were slower to make a saccade to the target when the fixation stimulus was still present. Strikingly, infants did not show clear evidence of the pre-saccadic components observed in adults which are thought to reflect cortical saccade planning processes. They did, however, show a left frontal positivity, which we suggest reflects cortical disinhibition of the colliculus initiated by fixation stimulus offset, and clear post-saccadic lambda waves. These results indicate that the frontal cortex already plays a role in action control by 6 months of age, while other aspects of cortical action planning may not yet be present in certain task situations.
Csibra
G
G
Cognitive Development Unit, Medical Research Council, London, UK. g.csibra@cdu.ucl.ac.uk
Tucker
L A
LA
Johnson
M H
MH
D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009474:Neurons / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012438:Saccades / Q000502:physiology*