Abstract
OBJECTIVE: The mismatch negativity (MMN) reflects automatic cognitive function in response to auditory stimulation. The MMN to duration deviant (d-MMN) amplitude is known to be lower in children with autism spectrum disorder (ASD) than in healthy controls (HCs). Moreover, the d-MMN is known to be a trait maker of schizophrenia because it is unaffected by the duration of illness. This study aimed to identify robust tools to distinguish adults with ASD from HCs by measuring the d-MMN. METHODS: Fifteen adults with ASD (age range, 20-40 years) and 20 HCs were compared. After excluding patients with a low intelligence quotient, those using central nervous system stimulants, and those with excessive alcohol consumption, we conducted an auditory oddball task to measure the d-MMN. RESULTS: Compared with HCs, the patients with ASD showed significantly shorter d-MMN latencies for Fz and Cz. CONCLUSION: The present findings suggest that the automatic cognitive function indicated by MMN amplitude might be improved by growth. Alternatively, the hypersensitivity indicated by d-MMN latencies suggests that it could persist into adulthood. SIGNIFICANCE: The d-MMN latency was shortened in patients with ASD compared with HCs. We believe that this is the first report to reveal that hypersensitivity in ASD as reflected by a shortened d-MMN latency should be maintained, even in adults.