Effects of alcohol on auditory pre-attentive processing of four sound features: evidence from mismatch negativity.

RATIONALE: Studies have shown that alcohol could impair automatic pre-attentive change detection. However, several earlier studies which investigated alcohol-induced effects on single auditory feature independently were different from each other on the results. Meanwhile, only few auditory features have been investigated yet. Therefore, it is meaningful to investigate effects of alcohol on multiple auditory features in one experiment.
OBJECTIVES: This study investigates the effects of alcohol on automatic pre-attentive change detection of four kinds of auditory features (frequency, intensity, location, and duration) in one experiment.
METHODS: This study, using multi-feature oddball paradigm, compares and analyzes mismatch negativity (MMN) elicited by four kinds of auditory features (frequency, intensity, location, and duration), of 12 participants, under alcohol (0.65 g/kg) and non-alcohol condition.
RESULTS: Compared to non-alcohol condition, amplitudes of all the four MMN types significantly declined under alcohol condition, and their amplitude decline ratios decreased as deviant magnitude became larger. Latencies of frequency and intensity MMN were delayed while latencies of location and duration MMN were not delayed significantly.
CONCLUSION: Alcohol impaired automatic pre-attentive change detection of all the four auditory features (frequency, intensity, location, and duration). However, the alcohol-induced impairment magnitude on automatic pre-attentive detection of the four auditory features was different from each other. According to analysis of amplitude, frequency seems to be affected most among the four auditory features. According to analysis of latency, only frequency and intensity were affected.