Internally driven vs. externally cued movement selection: a study on the timing of brain activity

• Published in: Brain research. Cognitive brain research Vol. 9; no. 3; pp. 261 - 269
• Main Authors: Thut, Gregor, Hauert, Claude-Alain, Viviani, Paolo, Morand, Stéphanie, Spinelli, Laurent, Blanke, Olaf, Landis, Theodor, Michel, Christoph
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2000; Elsevier Science
• Subjects: Adult; Anatomical correlates of behavior; Behavioral psychophysiology; Biological and medical sciences; Brain Mapping; Electroencephalography; Event related potential; Evoked Potentials, Motor - physiology; Female; Frontal Lobe - physiology; Fundamental and applied biological sciences. Psychology; Humans; Internally driven vs. externally cued motor task; Male; Motor Cortex - physiology; Motor imagery; Movement - physiology; Movement selection; Occipital Lobe - physiology; Parietal Lobe - physiology; Pre-motor cortex; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Psychomotor Performance - physiology; Reaction Time - physiology; Supplementary motor area; Movement selection; Motor imagery; Supplementary motor area; Pre-motor cortex; Event related potential; Internally driven vs. externally cued motor task; Human; Mental imagery; Motor pathway; Central nervous system; Body movement; Electrophysiology; Cognition; Premotor cortex; Motricity; Event evoked potential; Brain (vertebrata)
• ISSN: 0926-6410
• DOI: 10.1016/S0926-6410(00)00004-5

Brain imaging studies in man and single cell recordings in monkey have suggested that medial supplementary motor areas (SMA) and lateral pre-motor areas (PMA) are functionally dissociated concerning their involvement in internally driven and externally cued movements. This dichotomy, however, seems to be relative rather than absolute. Here, we searched for further evidence of relative differences and aimed to determine by what aspect of brain activity (duration, strength, or both) these might be accounted for. Event-related potentials (ERPs) were recorded while healthy, right-handed subjects selected one of three possible right hand digit movements based either on `internal' choice or `external' cues. The results obtained from ERP mapping suggest that movement selection evokes the same electrical brain activity patterns in terms of surface potential configurations in the same order and at the same strength independent of the selection mode. These identical configurations, however, differed in their duration. Combined with the results of a distributed source localization procedure, our data are suggestive of longer lasting activity in SMA during the `internal' and longer lasting activity in PMA during the `external' condition. Our results confirm previous findings in showing that SMA and PMA are distinctively involved in the two tasks and that this functional dichotomy is relative rather than absolute but indicate that such a dissociation can result from differences in duration rather than pure strength of activation.