Intelligence and Information Processing A Mismatch Negativity Analysis Using a Passive Auditory Backward-Masking Task

The relationship between mental ability (MA, Raven Progressive Matrices) and speed of information processing was examined by recording mismatch negativity (MMN) parameters from 41 women during passive listening to auditory standard and deviant stimuli with backward masking. The intertone interval (ITI) between the offset of the standard or deviant tone and the onset of the masking tone was varied between conditions (25, 50, or 150ms). Three versions of a trail-making test (Zahlen-Verbindungs-Test, ZVT) were also presented to obtain a behavioral index of information processing speed. Multiple regression analysis showed that the more difficult versions of the ZVT and midline frontal MMN latency at 25-ms ITI were both significant predictors of MA. Across all ITI conditions, the higher ability (HA) group exhibited a shorter MMN latency than the lower ability (LA) group. Finally, the HA group also had a larger MMN amplitude than the LA group for the 25-ms ITI condition. These results indicate that low-level auditory discrimination, indexed by MMN, contributes to individual differences in fluid intelligence. In this regard, MMN provides a valuable tool for examining individual differences in intelligence in individuals who are not able to comply with psychometric testing.