Development of a Classical Conditioning Task for Humans Examining Phasic Heart Rate Responses to Signaled Appetitive Stimuli: A Pilot Study.

Alessandra Sayão,Gail Tripp,Thomas Schultz Wenk,Heloisa Alves,Egas Caparelli-Dáquer,Mauricio Cagy,Emi Furukawa,Samantha Gutierrez-Arango

doi:10.3389/fnbeh.2021.639372

Abstract

Cardiac responses to appetitive stimuli have been studied as indices of motivational states and attentional processes, the former being associated with cardiac acceleration and latter deceleration. Very few studies have examined heart rate changes in appetitive classical conditioning in humans. The current study describes the development and pilot testing of a classical conditioning task to assess cardiac responses to appetitive stimuli and cues that reliably precede them. Data from 18 adults were examined. They were shown initially neutral visual stimuli (putative CS) on a computer screen followed by pictures of high-caloric food (US). Phasic cardiac deceleration to food images was observed, consistent with an orienting response to motivationally significant stimuli. Similar responses were observed to non-appetitive stimuli when they were preceded by the cue associated with the food images, suggesting that attentional processes were engaged by conditioned stimuli. These autonomic changes provide significant information about classical conditioning effects in humans.

Highlights

Cardiac responses have been studied as indices of both motivational/emotional states and attentional processes (Hunt and Campbell, 1997; Bradley, 2009)
Heart rate changes after unconditioned stimulus (US) were evaluated to examine whether the changes are reflective of motivational state or orienting responses
Visual inspection of the data suggest that the significant effect of time is driven by heart rate changes following the US and neutral stimulus (NS) preceded by Cue 1/conditioned stimulus (CS)+, while the iH values following the NS preceded by Cue 2/ CS– remained stable across the four intervals

Summary

INTRODUCTION

Cardiac responses have been studied as indices of both motivational/emotional states and attentional processes (Hunt and Campbell, 1997; Bradley, 2009). Cardiac Responses to Appetitive Stimuli (Nederkoorn et al, 2000), repeated presentations of positive food images (Kuoppa et al, 2016), and anticipating the opportunity to perform a task to earn money (Rakover and Levita, 1973) Such acceleration is thought to reflect autonomic arousal and a heightened emotional state triggered by the presence of motivationally significant stimuli and mediated by sympathetic nervous system activation (Fowles et al, 1982; Richter, 2012). Responses reflective of reward prediction errors may be observed when the US is not consistent with the CS preceded it (Kamin, 1967; Rescorla and Wagner, 1972)

MATERIALS AND METHODS

RESULTS

DISCUSSION

ETHICS STATEMENT