"Memory-scanning" event-related potentials. Correlations with verbal and performance scores.

Auditory and visual event-related potentials (ERPs) to a digit probe identification task in a modified Sternberg paradigm have been compared with psychological tests of verbal and performance ability (WAIS) in 19 healthy subjects. We have found a significant correlation between ERP amplitude and test scores. The higher the scores the "more negative" the responses. Correlations were stimulus-modality dependent. Auditory and visual ERPs were strongly correlated with "verbal" and "performance" IQ, respectively. The characteristics of these IQ-dependent electrophysiological features suggest that they may be related to the ability to allocate attention.