The addicted brain: cognitive biases in problematic drinkers with mild to borderline intellectual disability

Substance use disorders (SUD) are associated with several neurobiological disruptions, including biases in attention and approach/avoidance behaviour. The aims of this study were to compare the strength of cognitive biases between light and problematic drinkers, to explore the role of IQ on the cognitive biases and to study the psychometric qualities of the measures.

Participants (N = 130) were divided into four groups based on IQ and severity of alcohol use-related problems: light (n = 28) and problematic drinkers (n = 25) with (sub)average IQ and light (n = 33) and problematic drinkers (n = 44) with mild to borderline intellectual disability (MBID). All participants performed the visual dot probe task and the approach avoidance task to measure the strength of cognitive biases.

In contrast with the hypothesis, no cognitive biases were found in problematic drinkers. Full scale IQ nor level of craving influenced the strength of the cognitive biases in light and problematic drinkers, although IQ did influence task performance (i.e. large intra-individual, trial-to-trial variation in reaction time). The internal consistency of the visual dot probe task was good, whereas the internal consistency of the approach avoidance task was poor.

Cognitive biases seem to vary within the group of problematic drinkers as a whole. The psychometric qualities of the measures are problematic, especially in relation to the intra-individual variability in reaction time found in participants with MBID. Until the implications of this variability on the validity of implicit measures and establishing bias scores are more clear, the use of these measures in individuals with MBID calls for scrutiny.