title: Effects of ageing on cognitive task preparation as reflected by event-related potentials.
abstract: OBJECTIVE
  The anticipation of complex cognitive tasks involves effortful preparation being reflected in the contingent negative variation (CNV) of the event-related potential. In the literature there are contradictory results concerning the effect of age on this potential. We wanted to investigate effects of age, time-on-task, and task difficulty on the CNV.
  
  
  METHODS
  Young and middle-aged participants performed a visual search and a non-search task during an early and a late phase of a 6-h session.
  
  
  RESULTS
  Performance data revealed increased response times and error rates for middle-aged vs. young participants. Most importantly, an increased frontal CNV amplitude was found for the older participants, especially pronounced in the search task. A late positivity which was elicited to the offset of the preceding stimulus was increased for the middle-aged vs. young group in the visual search task only. There was no effect of time-on-task on performance, but the CNV became larger with time-on-task in the search task while it became smaller in the non-search task.
  
  
  CONCLUSIONS
  The results suggest an enhancement of effortful task preparation for middle-aged participants especially when the task is difficult.
  
  
  CONCLUSIONS
  This underlines the role of the CNV as a neurophysiological indicator for effortful cognitive preparation.
authors.affiliation: Leibniz Research Centre for Working Environment and Human Factors, Institute of Occupational Physiology, University of Dortmund, Germany. nele@wild-wall.de
authors.forename: Nele
authors.initials: N
authors.lastname: Wild-Wall
authors.forename: Joachim
authors.initials: J
authors.lastname: Hohnsbein
authors.forename: Michael
authors.initials: M
authors.lastname: Falkenstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D003265:Contingent Negative Variation / Q000502:physiology*; D004569:Electroencephalography; D004594:Electrophysiology; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion / Q000502:physiology; D013647:Task Performance and Analysis