School of Psychology, University of Birmingham, Birmingham, B15 2TT, United Kingdom
Centre for Human Brain Health, University of Birmingham, Birmingham, B15 2TT, United Kingdom.
J Neurosci. 2022 May 25;42(21):4394-4400. doi: 10.1523/JNEUROSCI.2364-21.2022. Epub 2022 May 2.
Emotion recognition abilities are fundamental to our everyday social interaction. A large number of clinical populations show impairments in this domain, with emotion recognition atypicalities being particularly prevalent among disorders exhibiting a dopamine system disruption (e.g., Parkinson's disease). Although this suggests a role for dopamine in emotion recognition, studies employing dopamine manipulation in healthy volunteers have exhibited mixed neural findings and no behavioral modulation. Interestingly, while a dependence of dopaminergic drug effects on individual baseline dopamine function has been well established in other cognitive domains, the emotion recognition literature so far has failed to account for these possible interindividual differences. The present within-subjects study therefore tested the effects of the dopamine D2 antagonist haloperidol on emotion recognition from dynamic, whole-body stimuli while accounting for interindividual differences in baseline dopamine. A total of 33 healthy male and female adults rated emotional point-light walkers (PLWs) once after ingestion of 2.5 mg haloperidol and once after placebo. To evaluate potential mechanistic pathways of the dopaminergic modulation of emotion recognition, participants also performed motoric and counting-based indices of temporal processing. Confirming our hypotheses, effects of haloperidol on emotion recognition depended on baseline dopamine function, where individuals with low baseline dopamine showed enhanced, and those with high baseline dopamine decreased emotion recognition. Drug effects on emotion recognition were related to drug effects on movement-based and explicit timing mechanisms, indicating possible mediating effects of temporal processing. Results highlight the need for future studies to account for baseline dopamine and suggest putative mechanisms underlying the dopaminergic modulation of emotion recognition. A high prevalence of emotion recognition difficulties among clinical conditions where the dopamine system is affected suggests an involvement of dopamine in emotion recognition processes. However, previous psychopharmacological studies seeking to confirm this role in healthy volunteers thus far have failed to establish whether dopamine affects emotion recognition and lack mechanistic insights. The present study uncovered effects of dopamine on emotion recognition in healthy individuals by controlling for interindividual differences in baseline dopamine function and investigated potential mechanistic pathways via which dopamine may modulate emotion recognition. Our findings suggest that dopamine may influence emotion recognition via its effects on temporal processing, providing new directions for future research on typical and atypical emotion recognition.
情绪识别能力是我们日常社交互动的基础。大量临床人群在这一领域表现出障碍，其中情绪识别异常在表现出多巴胺系统紊乱的障碍中尤为普遍（例如帕金森病）。尽管这表明多巴胺在情绪识别中起作用，但在健康志愿者中进行的多巴胺干预研究表现出混合的神经发现，并且没有行为调节。有趣的是，虽然在其他认知领域中已经确立了多巴胺能药物效应依赖于个体基线多巴胺功能，但迄今为止，情绪识别文献尚未解释这些可能的个体间差异。因此，本项在个体内的研究测试了多巴胺 D2 拮抗剂氟哌啶醇对动态全身刺激的情绪识别的影响，同时考虑了基线多巴胺的个体间差异。共有 33 名健康男性和女性在服用 2.5 毫克氟哌啶醇后和服用安慰剂后一次评估了情绪化的点光步行者（PLW）。为了评估情绪识别中多巴胺调制的潜在机制途径，参与者还进行了基于运动和计数的时间处理的指标。证实了我们的假设，氟哌啶醇对情绪识别的影响取决于基线多巴胺功能，其中基线多巴胺水平低的个体表现出增强的情绪识别，而基线多巴胺水平高的个体则降低了情绪识别。药物对情绪识别的影响与药物对运动和显式时间机制的影响有关，表明时间处理可能具有介导作用。结果强调了未来研究需要考虑基线多巴胺，并表明多巴胺对情绪识别的调制背后可能存在机制。在多巴胺系统受影响的临床条件下，情绪识别困难的高发率表明多巴胺参与了情绪识别过程。然而，迄今为止，寻求在健康志愿者中证实这一作用的先前精神药理学研究未能确定多巴胺是否影响情绪识别，并且缺乏机制上的见解。本研究通过控制基线多巴胺功能的个体间差异，揭示了多巴胺对健康个体情绪识别的影响，并通过调查多巴胺可能调节情绪识别的潜在机制途径来研究潜在的机制途径。我们的发现表明，多巴胺可能通过其对时间处理的影响来影响情绪识别，为典型和非典型情绪识别的未来研究提供了新的方向。
