Asymmetrical Attention to Gambling-related Stimuli and Pupillary Dilation in Response to Wins and Losses in Problem Gamblers
Abstract Gambling disorder and problem gambling are characterized by persistent and repetitive problematic gambling behavior. Attentional bias toward gambling-related stimuli such as casino chips, dice, roulette, etc. have been observed in problem gamblers (PGs), but it remains unclear whether stimuli in gambling tasks elicit greater attention and pupillary responses in PGs. To address this issue, we administrated PGs and non-problem gamblers (NPGs) a gambling task accompanied by eye-tracking measurements, in which the participants were required to choose one of the paired pictures to receive monetary rewards and avoid punishments. Concerning attentional allocation, PG showed a greater attentional preference for the right-hand pictures in the decision and feedback phases, and compared to NPGs, PGs’ attention was narrower and more focused on the left-hand pictures in the decision phase. Concerning pupillary dynamics indicative of noradrenergic locus coeruleus activity, pupillary dilation in response to rewards and punishments was observed only in PGs. Studies of unilateral spatial neglect have proposed that asymmetric attention is induced by hemispheric imbalance. Accordingly, asymmetrical allocation of attention by PGs may reflect hemispheric imbalance, and pupillary dynamics may reflect sensitivity to wins and losses.