RESUMEN
The rigid, stimulus-bound nature of drug seeking that characterizes substance use disorder (SUD) has been related to a dysregulation of motivational and early attentional reflexive and inhibitory reflective systems. However, the mechanisms by which these systems are engaged by drug-paired conditioned stimuli (CSs) when they promote the enactment of seeking habits in individuals with a SUD have not been elucidated. The present study aimed behaviourally and electrophysiologically to characterize the nature of the interaction between the reflexive and reflective systems recruited by CSs in individuals with a smoking habit. We measured the behavioural performance and associated event-related potentials (ERPs) of 20 individuals with a smoking habit and 20 controls, who never smoked regularly, in a modified Go/NoGo task during which smoking-related CSs, appetitive and neutral pictures, presented either in first or third-person visual perspective were displayed 250 ms before the Go/NoGo cue. We show that smoking-related cues selectively influence early incentive motivation-related attention bias (N2 after picture onset), motor readiness and behavioural inhibition (Go-P3, NoGo-P3 and Pc) of individuals with a smoking habit only when presented from a first-person visual perspective. These data together identify the neural signature of the aberrant engagement of the reflexive and reflective systems during the recruitment of an incentive habit by CSs presented as if they had been response-produced, that is, as conditioned reinforcers.
Asunto(s)
Señales (Psicología) , Electroencefalografía , Humanos , Potenciales Evocados/fisiología , Fumar , Hábitos , Tiempo de Reacción/fisiologíaRESUMEN
There is abundant literature demonstrating that processing emotional stimuli modulates inhibitory control processes. However, the reverse effects, namely, how cognitive inhibition influences the processing of emotional stimuli, have been considerably neglected. This ERP study tries to fill this gap by studying the bidirectional interactions between emotional language and inhibitory processes. To this end, participants read emotional sentences, embedded in a cue-based Go-NoGo task. In Experiment 1, the critical emotional adjective preceded the Go-NoGo visual cue. The ERPs showed a significant reduction in the inhibition-related N2 component in NoGo trials when they were preceded by negative adjectives, compared to positive or neutral adjectives, indicating a priming-like effect on inhibitory control. Consistently, the estimated source of this interaction was the dorsomedial PFC, a region associated with inhibitory and control processes. In Experiment 2, the Go-NoGo cue preceded the emotional adjective, and the ERPs showed a sustained, broadly distributed LPP-like positivity for NoGo negative trials, relative to all the other conditions. In this case, the presetting of an inhibition state modulated the processing of negatively charged words. Together, the two experiments suggest a mutual facilitation between inhibitory control and negative valence, supporting thereby recent integrative theories of cognition-emotion interactions.