[Auditory evoked potentials and alcohol: characteristics of the mismatch negativity component in alcoholism]

The aim of this work is to review the effects of alcohol on the MMN component, to discuss its viability as a vulnerability marker for alcoholism, and to link it with the P300 component.

Alcohol alters the P300 and MMN components of auditory evoked potentials. In alcoholism, the alterations observed in the P300 component in risk subjects have been seen as markers of susceptibility to development of the illness. In the case of the MMN component, on the other hand, to date its viability as a vulnerability marker has only been evaluated in three studies, with varying results. While two of them found no differences, in the third and most recent it was found that risk subjects presented an increase in the amplitude of the MMN, which was interpreted as a reflection of the cortical hyperexcitability suggested by other authors and which was also reflected in the decrease in the P300 amplitude.

The results obtained do not enable us to draw conclusions about whether the MMN component is altered in risk subjects for alcoholism. The differences in the studies that have been conducted could be due to the variations in the characteristics of the samples used or of the evaluation of the characteristics of MMN. The analysis of previous work on P300 or MMN suggests that broader, more homogeneous samples should be used in future research and that, in addition to the MMN peak, its mean amplitude in successive intervals, together with its two subcomponents should also be evaluated separately.