Does alcohol automatically capture drinkers' attention? Exploration through an eye-tracking saccadic choice task

RATIONALE

Dominant theoretical models postulate the presence of an automatic attentional bias (AB) towards alcohol-related stimuli in alcohol use disorder, such AB constituting a core feature of this disorder. An early alcohol AB has been documented in subclinical populations such as binge drinking (i.e., a drinking pattern prevalent in youth and characterized by repeated alternation between alcohol intoxications and withdrawals, generating cerebral consequences). However, the automatic nature of AB remains to be established.

OBJECTIVES

We investigated the automatic nature of AB in binge drinkers through the saccadic choice task. This eye-tracking paradigm consistently highlights the extremely fast and involuntary saccadic responses elicited by faces in humans, relative to other object categories. Through an alcohol-related adaptation of the saccadic choice task, we tested whether the early and automatic capture of attentional resources elicited by faces can also be found for alcohol-related stimuli in binge drinkers, as predicted by theoretical models.

METHODS

Forty-three binge drinkers and 44 control participants performed two versions of the saccadic choice task. In the original version, two images (a face, a vehicle) were displayed on the left and right side of the screen respectively. Participants had to perform a saccade as fast as possible towards the target stimulus (either face or vehicle). In the alcohol-related version, the task was identical, but the images were an alcoholic beverage and a non-alcoholic stimulus.

RESULTS

We replicated the automatic attraction towards faces in both groups, as faces generated higher saccadic accuracy, speed, and amplitude than vehicles, as well as higher corrective saccade proportion. Concerning the alcohol-related adaptation of the task, groups did not differ for the accuracy, speed, and amplitude of the first saccade towards alcohol. However, binge drinkers differed from controls regarding the proportion of corrective saccade towards non-alcoholic stimuli after an error saccade towards alcohol, suggesting the presence of an alcohol disengagement bias specific to binge drinkers.

CONCLUSIONS

Alcohol-related AB in binge drinkers is not characterized by an early and automatic hijacking of attention towards alcohol. This AB rather relies on later and more controlled processing stages, namely a difficulty to disengage attentional resources from alcohol-related stimuli.

Post-search IOR: Searching for inhibition of return after search

Previous research has indicated that Inhibition of return (IOR) supports visual search by discouraging the re-inspection of recently inspected items during search. However, it is not clear whether IOR persists after a search is completed or whether this depends on the presence of a further search in the same display. To investigate this issue, we had participants search consecutively twice in the same display (Experiment 1). Immediately after the end of the first search and after the end of the second search we probed an item which had been recently inspected or not in the previous search. The results showed that IOR as measured by the saccadic latency to the probed items was absent after the end of each of the two successive searches. In Experiment 2, we measured both saccadic latencies and manual responses in a single-search paradigm. We found that IOR during and after the search was present for saccadic responses but absent for manual responses. This suggests that IOR during and after a visual search depends on the modality of the response and the number of required searches.