Time predictability modulates pre-supplementary motor area neuronal activity.
Two monkeys were trained in a delayed sequential motor task in which the time interval between events and the delay duration were either fixed or variable. Single-unit neuronal activity was recorded in the pre-supplementary motor area (pre-SMA). During the delay, we observed a gradual increase in activity (build-up pattern) in the fixed but not in the variable condition. In the former but not in the latter, the monkey had the opportunity to estimate time duration. Consequently, the build-up pattern observed in the pre-SMA might represent the neuronal substrate of a time accumulator system proposed by previous authors on the basis of functional imaging data. Such a system could play a critical role in the working memory of temporal information.
Akkal
D
D
Laboratoire de Neurophysiologie, UMR CNRS, 5543, Université Victor Segalen, 146, rue Léo Saignat, 33076 Bordeaux, France.
Escola
L
L
Bioulac
B
B
Burbaud
P
P
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D003071:Cognition / Q000502:physiology; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005625:Frontal Lobe / Q000502:physiology*; D000882:Haplorhini; D009068:Movement / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*