The Effects of Multimodal Distractors on Sign-trackers and Goal-trackers Attention.

During Pavlovian conditioning, Sign-Tracker (ST), Goal-Tracker (GT), and Intermediate (IN) phenotypes emerge, as characterized by the degree to which an individual attributes incentive salience to reward-associated cues. These operationally defined phenotypes differ in other respects: In human studies, STs tend to favor bottom-up attention, while GTs tend to favor top-down attention. There is some limited evidence that rats exhibit similar patterns during Pavlovian conditioning. To substantiate this model, we tested the hypothesis that introducing light and auditory distractors would disproportionately impair the signal detection performance of ST rats, given their propensity for bottom-up attention processing, as opposed to GT rats, who rely more on top-down strategies. To this end, we assessed detection performance in 86 Long-Evans rats by introducing both visual and auditory distractors of varying intensities. This approach aimed to investigate the limits of attentional control among ST, GT, and IN rats across six variants of a sustained attention task. Although distractors impaired performance, contrary to initial expectations, the extent of this impairment varied across phenotypes and tasks, indicating a more nuanced relationship between attentional mechanisms and susceptibility to distractions than previously posited. The present results suggest the occurrence of a complex interplay of attentional mechanisms that may not align completely with the ST/GT dichotomy as traditionally presented. These findings have potential implications for understanding individual differences in attentional control and susceptibility to distractions, which could relate to addiction vulnerability.