Neuropsychological performance and cognitive olfactory event-related brain potentials in young and elderly adults.

The P3 event-related brain potential (ERP) reflects neuroelectric activity related to the speed of cognitive processing and allocation of attentional resources. The objective of the present study was to assess the relationship between the P3 and Slow Wave components of the olfactory event-related potential (OERP) with neuropsychological performance in young (n = 16) and elderly (n = 16) adults. OERPs were recorded monopolarly from midline electrode sites while subjects estimated the odor magnitude of each stimulus, eliciting highly reproducible P3s. Results showed that the late cognitive components (P3 amplitude, P3 latency and Slow Wave area) decline with age and that this decreased neuronal efficiency is associated with reductions in the neuropsychological performance indexed by the Trail Making Test and the California Verbal Learning Test.