title: Individual differences in the influence of task-irrelevant Pavlovian cues on human behavior.
abstract: Pavlovian-to-instrumental transfer (PIT) refers to the process of a Pavlovian reward-paired cue acquiring incentive motivational proprieties that drive choices. It represents a crucial phenomenon for understanding cue-controlled behavior, and it has both adaptive and maladaptive implications (i.e., drug-taking). In animals, individual differences in the degree to which such cues bias performance have been identified in two types of individuals that exhibit distinct Conditioned Responses (CR) during Pavlovian conditioning: Sign-Trackers (ST) and Goal-Trackers (GT). Using an appetitive PIT procedure with a monetary reward, the present study investigated, for the first time, the extent to which such individual differences might affect the influence of reward-paired cues in humans. In a first task, participants learned an instrumental response leading to reward; then, in a second task, a visual Pavlovian cue was associated with the same reward; finally, in a third task, PIT was tested by measuring the preference for the reward-paired instrumental response when the task-irrelevant reward-paired cue was presented, in the absence of the reward itself. In ST individuals, but not in GT individuals, reward-related cues biased behavior, resulting in an increased likelihood to perform the instrumental response independently paired with the same reward when presented with the task-irrelevant reward-paired cue, even if the reward itself was no longer available (i.e., stronger PIT effect). This finding has important implications for developing individualized treatment for maladaptive behaviors, such as addiction.
authors.affiliation: Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna Cesena, Italy ; Department of Psychiatry, University of Cambridge Cambridge, UK ; Behavioural and Clinical Neuroscience Institute, Department of Psychology, University of Cambridge Cambridge, UK.
authors.forename: Sara
authors.initials: S
authors.lastname: Garofalo
authors.affiliation: Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna Cesena, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: di Pellegrino
keywords: Goal-Tracker; Pavlovian-to-instrumental transfer; Sign-Tracker; cue-controlled behavior; reinforcement learning