title: Hemispheric differences in VEP elicited by mental arithmetic and tachistoscopically presented spatial transformation tasks.
abstract: Recent studies have furnished evidence of hemispheric asymmetry in the EEG and event-related potentials in man. Face-validated tasks as verbal and nonverbal ones (A: mental arithmetic; B: detection of a target in the hand of a manikin in different positions) were tachistoscopically presented to check side differences of VEP parameters in 5 healthy right-handed subjects. The EEG was recorded from C3, C4, P3 and P4 referenced to linked ears. The mean peak latencies of averaged VEPs were P1: 107 ms, N1: 142 ms, P2: 203 ms, N2: 265 ms, P3: 357 ms. No consistent treatment effects were obtained for peak latencies. Regardless of side differences, the attention related VEP amplitudes P1-N1 and N1-P2 were higher in A. Rightleft differences were found to be higher for visual-spatial transformation, except P2-N2 amplitude. The asymmetry of amplitudes suggests a higher activity of the right hemisphere in B. A possible description of dynamic variations due to learning and changes of strategy during repetitive mental activity by means of changes in EP asymmetry will be of interest for further investigations.
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D003071:Cognition / Q000502:physiology; D004569:Electroencephalography; D005074:Evoked Potentials, Visual; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008433:Mathematics; D008606:Mental Processes / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D014705:Verbal Behavior / Q000502:physiology