P Gordon Bazana | Search PubMed

PubMed2002

Intelligence and information processing during an auditory discrimination task with backward masking: an event-related potential analysis.

The relation between mental ability and auditory discrimination ability was examined by recording event-related potentials from 60 women during an auditory oddball task with backward masking. Across conditions that varied in intensity and in the interval between the target and masking stimuli, the higher ability (HA) group exhibited greater response accuracy, shorter response times, larger P3 amplitude, and shorter P3 latency to target stimuli than the lower ability (LA) group. When instructed to ignore the stimuli, the HA group exhibited shorter mismatch negativity latency to deviant tones than the LA group. The greater speed and accuracy of auditory discrimination for the HA group, observed here with multiple measures, is not a consequence of response strategy, test-taking ability, or attention deployment.

Evoked Potentials↗

PubMed2000

Individual differences in mismatch negativity measures of involuntary attention shift.

OBJECTIVE: The purpose of this study was to compare the automatic detection of deviance in introverts and extraverts. Event-related potentials were recorded to standard and deviant stimuli. These were presented either rapidly or slowly. Stimuli that are presented slowly may intrude into consciousness. METHODS: Twenty subjects were tested and divided into introverted and extraverted groups. A 500 Hz standard stimulus was presented on 85% of trials. On the remaining 15% of trials, a 750 Hz deviant was presented. In separate conditions, stimuli were presented rapidly (every 500 ms) or slowly (every 1500 ms). Subjects ignored the stimuli while reading. RESULTS: The deviant stimulus elicited a mismatch negativity (MMN) in both conditions. No inter-group differences in the MMN emerged when a rapid rate of presentation was employed. When a slower rate was employed, a late negativity was significantly larger for the extraverted than the introverted group. This was followed by a late positive wave. CONCLUSION: The late negative-positive complex is thought to reflect intrusiveness. It would therefore appear that extraverts are more distractible than introverts when stimuli are presented slowly.

Acoustic Stimulation↗