Acute nicotine alteration of sensory memory impairment in smokers with schizophrenia.

Context: Patients with schizophrenia have a high rate of cigarette smoking and also exhibit profound deficits in sensory processing, which may in part be ameliorated by the acute actions of smoke-inhaled nicotine. The mismatch negativity (MMN), a preattentive event-related potential index of auditory sensory memory, is diminished in schizophrenia. The MMN is increased in healthy controls with acute nicotine.

Event-related potentials in young and elderly adults during a visual spatial working memory task.

The P300 event-related brain potential (ERP) was examined in 14 young (20-29 years of age) and 16 elderly (60-82 years of age) subjects during the performance of a visuospatial memory task requiring recognition of locations. Elderly and young adults exhibited similar recognition accuracy, but recognition reaction times were significantly slower in the elderly. Midline P300 amplitudes recorded in response to visuospatial probe stimuli were significantly attenuated in the elderly, and, depending on the nature of the probe, P300 latency-derived indices indicated that both cognitive and motoric slowness characterized visuospatial recognition in the aged.

Effects of stimulus modality and response mode on the P300 event-related potential differentiation of young and elderly adults.

The P300 event-related brain potential (ERP) was examined in 14 young (20 - 29 years of age) and 16 elderly (60 - 82 years of age) adult subjects during the performance of auditory and visual discrimination tasks requiring silent counting or key pressing in response to target stimuli. P300 latencies were longer in elderly (vs young) adults and in visual (vs auditory) tasks, and visual tasks elicited larger P300 amplitudes than auditory tasks in both age groups. Neither stimulus modality nor response mode affected P300 differentiation of young and elderly subjects.