P2 flash visual evoked response delay may be a marker of cognitive dysfunction in healthy elderly volunteers

Int Psychogeriatr. 1996 Winter;8(4):549-59. doi: 10.1017/s1041610296002876.

Abstract

In an earlier study, 31 healthy elderly volunteers had normal cognitive function as measured by the Mini-Mental State Examination. Twenty-seven returned for further memory testing using the Wechsler Memory Scale-Revised (WMS-R). The P2 latency of the flash visual evoked response was positively correlated with age (p = .0008), but was not significantly related to gender. Nine of these 27 putatively healthy subjects had a delayed P2, suggestive of dementia. Although unaware of any memory deficits, 5 of the 27 had WMS-R Visual Memory Span percentile scores 1 or more standard deviations less than age-matched controls. Four of the five also had a significantly delayed P2 component. This positive correlation, adjusted for age, between poor Visual Memory Span performance and a delayed P2 was statistically significant (p < .025). These findings suggest that a delayed P2 in putatively healthy subjects is indicative of a visuospatial deficit which might be a precursor of dementia later.

MeSH terms

  • Aged
  • Cognition Disorders / diagnosis*
  • Cognition Disorders / physiopathology
  • Dementia / diagnosis*
  • Dementia / physiopathology
  • Electroencephalography
  • Evoked Potentials, Visual / physiology*
  • Female
  • Frontal Lobe / physiopathology
  • Humans
  • Male
  • Mental Recall / physiology
  • Mental Status Schedule
  • Middle Aged
  • Photic Stimulation
  • Reaction Time / physiology
  • Reference Values
  • Signal Processing, Computer-Assisted
  • Wechsler Scales