Visual and auditory event-related brain potentials and task complexity: String length, variance, P300 amplitude and latency and the fluid and crystallized theory of intelligence

his study investigated the relationship between ERP variables such as P300 amplitude, P300 latency, string length, intrasubject variance, and reaction organization time and psychometric intelligence. The reaction time-IQ relationship was also assessed. The Hendricksons' pulse train hypothesis, which is a neural theory which states that intelligence is a function of low error rates in the nervous system was examined by assessing the relationship between the ERP variables and the Kaufman Adolescent and Adult Intelligence Test (KAIT), a valid and reliable measure of fluid and crystallized IQ. Subjects were 28 individuals between the ages of 18 and 45 (14 men and 14 women) who were placed in either the high (mean IQ = 116) or low ability (mean IQ = 90) group based on their KAIT Composite IQ scores. A shifting attention ERP paradigm utilizing both visual and auditory stimuli was administered to each subject. The high ability subjects were more accurate in their responses to both visual and auditory targets and had faster reaction times than the low ability group. No differences between the ability groups were found for P300 amplitude, P300 latency, string length, or variance measures (ps...