Preserved crossmodal integration of emotional signals in binge drinking

Binge drinking is an alcohol consumption pattern with various psychological and
cognitive consequences. As binge drinking showed qualitatively comparable cognitive
impairments to those reported in alcohol-dependence, a continuum hypothesis
suggests that this habit would be a first step toward alcohol-related disorders.
Besides these cognitive impairments, alcohol-dependence is also characterized by
large-scale deficits in emotional processing, particularly in crossmodal contexts, and
these abilities have scarcely been explored in binge drinking. Emotional decoding,
most often based on multiple modalities (e.g., facial expression, prosody or gesture),
yet represents a crucial ability for efficient interpersonal communication and social
integration. The present study is the first exploration of crossmodal emotional processing
in binge drinking, in order to test whether binge drinkers already present the emotional
impairments described among alcohol-dependent patients, in line with the continuum
hypothesis. Twenty binge drinkers and 20 matched controls performed an experimental
task requiring the identification of two emotions (happiness or anger) presented
in two modalities (visual or auditory) within three conditions (unimodal, crossmodal
congruent or crossmodal incongruent). In accordance with previous research in binge
drinking and alcohol-dependence, this study was based on two main hypotheses.
First, binge drinkers would present a reduced facilitation effect (i.e., classically indexed
in healthy populations by faster reaction times when two congruent modalities are
presented simultaneously). Second, binge drinkers would have higher difficulties to
inhibit interference in incongruent modalities. Results showed no significant difference
between groups in emotional decoding ability, whatever the modality or condition.
Control participants, however, appeared slower than binge drinkers in recognizing facial
expressions, also leading to a stronger facilitation effect when the two modalities were
presented simultaneously. However, findings did not show a disrupted facilitation effect
in binge drinkers, whom also presented preserved performance to inhibit incongruence
during emotional decoding. The current results thus suggest that binge drinkers do
not demonstrate a deficit for emotional processing, both in unimodal and crossmodal
contexts. These results imply that binge drinking might not be characterized by
impairments for the identification of primary emotions, which could also indicate that
these emotional processing abilities are well-preserved at early stages of excessive
alcohol consumption