From skinner box to daily life: Sign-tracker phenotype co-segregates with impulsivity, compulsivity, and addiction tendencies in humans

Abstract

Pavlovian conditioning holds the potential to incentivize environmental cues, leading to approach behavior toward them, even outside our awareness. Animal models suggest that this is particularly true for the so-called sign-tracker (ST) phenotype, which is considered to reflect a predisposition toward developing addiction-related behaviours. Despite its potential clinical relevance, few studies have demonstrated the translational validity of this model, likely due to difficulties in studying Pavlovian processes in humans. To fill this gap, we combined an ecological momentary assessment with ambulatory peripheral autonomic monitoring to test the hypothesis that traits associated with ST in preclinical studies would be associated with attribution of high incentive salience to reward-related cues. Several times for 2 days, participants were asked to rate the attractiveness of several preselected ecological rewards (e.g., coffee) and the preceding cues (the smell of coffee) while their electrocardiogram was recorded. While no absolute difference in subjective and physiological measures of motivational approach to daily cues compared with rewards emerged, individuals with high levels of impulsivity, obsessive-compulsive, and addiction-prone behaviors rated as more attractive and showed a greater increase in sympathetic arousal to cues versus rewards. The opposite pattern emerged for those with low levels in those dispositional traits, who responded more (both subjectively and physiologically) to rewards compared with their preceding cues. This study represents an attempt to answer the call to parcel complex behaviors into smaller constructs, improving the early detection of those who are vulnerable to develop psychopathological disorders, particularly in the domain of impulse control such as addiction.

Opening new vistas on obsessive-compulsive disorder with the observing response task

“…Crucially, whereas goal-trackers and intermediate animals performed fewer dysfunctional eOLPs once the shock contingency was removed, sign-trackers did not decrease their dysfunctional checking behaviour after the contingency between maladaptive checking and shock delivery had been decoupled. This aligns with the notion of persistent, dysfunctional behavioural aberrations analogous to compulsive checking in humans, as well as pointing to the phenotypic susceptibility of sign-tracking subjects to engage in compulsive behaviour, as described in the addiction literature (Flagel et al, 2009 ; Tomie et al, 2008 ; Robinson et al, 2018 ; Schettino et al, 2022 ). This emerging research hence supports the utility of the ORT as an objective translational tool for illuminating underlying processes akin to the maladaptive checking observed in OCD patients, allowing complementary studies to be conducted in rodents (which would allow for causal manipulations of checking through pharmacological and neural manipulations) and humans (both healthy participants and patients, where there is potential for functional imaging and subjective, in addition to objective, measures).…”

Sign-Tracking and Goal-Tracking in Humans: Utilising Eye-Tracking in Clinical and Non-Clinical Populations

“…Cope et al [7] measured behavioural impulsivity using the Barratt Impulsivity Scale and found that higher scores were associated with sign-tracking behaviour in young adults, in accordance with Garofalo & di Pellegrino [16]. Using an experience sampling design to investigate real-life attribution of high incentive salience to reward-related cues, Schettino et al [35] found that high levels of impulsivity, obsessive-compulsive tendencies and addiction-prone tendencies predicted higher attractiveness of the sign, compared with the goal. Colaizzi et al [6] measured externalising tendencies using parent-report questionnaires (Child Behaviour Checklist and Early Adolescent Temperament Questionnaire), and reported increased ADHD-like symptoms, increased fear, and lower inhibitory control in ST, though they found no group differences in self-reported or behavioural measures of inhibition and impulsivity.…”

Resting-state brain activation patterns and network topology distinguish human sign and goal trackers

“…After reading and signing the informed consent, participants were asked to complete a series of online questionnaires (via Qualtrics) assessing socio-demographic and medical information (e.g., sex, age, education level, medical or psychiatric diagnosis, substance use). If inclusion criteria were met, participants were subsequently evaluated for dispositional psychological characteristics that have been shown to co-segregate with ST/GTs (e.g., impulsiveness, obsessive-compulsive tendencies, [32]) (see S1 for details on the administered questionnaires). Our research protocol consisted of two separate sessions: during the rst, behavioral data were acquired, while the second was entirely dedicated to the RSFC data acquisition.…”