Department of Clinical Psychology, University of Siegen, Siegen, Germany.
Department of Psychology, University of Marburg, Marburg, Germany.
Psychophysiology. 2021 Nov;58(11):e13912. doi: 10.1111/psyp.13912. Epub 2021 Aug 13.
While the examination of conditioned cardiac responses is well established in human fear conditioning research, comparable studies using less-aversive or rather appetitive unconditioned stimuli (UCS) are sparse and results are mixed. Therefore, the aim of this study was a systematic analysis of cardiac reactions in aversive and appetitive conditioning. Olfactory stimuli were used as unconditioned stimuli as they are suitable reinforcers in both an aversive and an appetitive conditioning offering the opportunity for a comparison between conditioned responses. In total, n = 86 participants took part in both an aversive and an appetitive differential conditioning task with a counterbalanced order across participants. Aversive or appetitive odors, respectively, served as UCS and neutral geometrical figures as CS. Subjective ratings, skin conductance response (SCRs), and evoked cardiac reactions were analyzed and compared between tasks. Conditioned responses in subjective ratings could be observed in both aversive conditioning and appetitive conditioning, while SCRs discriminated between CS+ and CS- in aversive conditioning only. Regarding conditioned cardiac responses, the deceleration for the CS+ was longer than for the CS- in both tasks. In addition, a higher deceleration magnitude and a shorter acceleration for the CS+ as compared to the CS- were found in aversive but not in appetitive conditioning. There were medium-size correlations between aversive and appetitive CRs for subjective ratings and none for physiological responses. The results suggest similarities between cardiac response patterns in aversive and appetitive conditioning, which implies that bradycardia in conditioning might not be fear-specific but presents a valence-independent CS-elicited bradycardia.
虽然条件性心脏反应的检查在人类恐惧条件反射研究中已经得到很好的建立，但使用不那么厌恶或更开胃的非条件刺激（UCS）进行可比研究却很少，而且结果也不一致。因此，本研究的目的是对厌恶和开胃条件反射中的心脏反应进行系统分析。嗅觉刺激被用作非条件刺激，因为它们在厌恶和开胃条件反射中都是合适的强化物，为条件反应之间的比较提供了机会。总共有 86 名参与者参加了厌恶和开胃的差异条件反射任务，参与者之间的顺序是平衡的。厌恶或开胃的气味分别作为 UCS，中性几何图形作为 CS。对主观评分、皮肤电反应（SCR）和诱发的心脏反应进行了分析和比较。在厌恶和开胃条件反射中都可以观察到条件反应，而 SCR 仅在厌恶条件反射中区分 CS+和 CS-。关于条件性心脏反应，CS+的减速时间比 CS-长。此外，与 CS-相比，在厌恶条件反射中，CS+的减速幅度更高，加速时间更短。在厌恶条件反射中，主观评分和生理反应之间的条件反射存在中等大小的相关性，而在开胃条件反射中则没有。这些结果表明，厌恶和开胃条件反射中的心脏反应模式存在相似性，这意味着条件反射中的心动过缓可能不是恐惧特异性的，而是呈现出与效价无关的 CS 诱发的心动过缓。
