Abstract
Perceptual history – learning from perceptual experiences (Jeong et al, 2014) – influences item salience and processing efficiency (Kahnt & Tobler, 2017; James et al. 2000). From the addiction literature, it’s found that an addiction-related cue acquires increased neural reactivity in sensory cortex (Hanlon et al., 2014). We hypothesized that repeat exposure to addictive substances induces sensory system plasticity leading to increased salience and sensory processing speed of substance-related items(Robinson & Berridge 2008; Yalechkov et al., 2010). We selected an addictive substance that a majority of the American population engages with: alcohol (Grant et al., 2017). Participants chose three drink types - preferred, aversive, and neutral - from 16 alcohol categories. We predicted that preferred drinks would show faster processing speed because of their enhanced perceptual history. In three experiments, we measured performance with sensory processing efficiency tasks. Experiments 1 and 2 consisted of oddball visual search (VS), where successful localization of the target required processing all images displayed. In homogeneous VS (Exp. 1, n=32), participants searched for the unique image in a visual display of many identical images. In heterogenous VS (Exp. 2, n=31) participants searched for the unique category image (target) in a display of varied images from a distractor category. In task three, multiple object tracking (Exp. 3, n=33), participants visually tracked a subset of moving alcoholic beverage images. In Experiment 1, displays with preferred items had shortest reaction times. In Experiment 2, the same preferred item facilitation was found. In Experiment 3, accuracy was highest when tracking preferred items, while preferred distractors reliably decreased accuracy indicating that processing preferred items was automatic. Overall, task performance was enhanced with task-relevant preferred items and hindered with task-irrelevant. The coupling of perceptual history (preference) with high reward (addictive substances) leads to neuro-plasticity observable in measures of sensory salience.