Department of Clinical and Health Psychology, University of Vienna, Vienna, Austria.
Department of Cognition, Emotion and Methods in Psychology, University of Vienna, Vienna, Austria.
Hum Brain Mapp. 2024 Mar;45(4):e26645. doi: 10.1002/hbm.26645.
Rewards are a broad category of stimuli inducing approach behavior to aid survival. Extensive evidence from animal research has shown that wanting (the motivation to pursue a reward) and liking (the pleasure associated with its consumption) are mostly regulated by dopaminergic and opioidergic activity in dedicated brain areas. However, less is known about the neuroanatomy of dopaminergic and opioidergic regulation of reward processing in humans, especially when considering different types of rewards (i.e., social and nonsocial). To fill this gap of knowledge, we combined dopaminergic and opioidergic antagonism (via amisulpride and naltrexone administration) with functional neuroimaging to investigate the neurochemical and neuroanatomical bases of wanting and liking of matched nonsocial (food) and social (interpersonal touch) rewards, using a randomized, between-subject, placebo-controlled, double-blind design. While no drug effect was observed at the behavioral level, brain activity was modulated by the administered compounds. In particular, opioid antagonism, compared to placebo, reduced activity in the medial orbitofrontal cortex during consumption of the most valued social and nonsocial rewards. Dopamine antagonism, however, had no clear effects on brain activity in response to reward anticipation. These findings provide insights into the neurobiology of human reward processing and suggest a similar opioidergic regulation of the neural responses to social and nonsocial reward consumption.
奖励是一类广泛的刺激物，它们能诱导趋近行为以帮助生存。大量来自动物研究的证据表明，想要（追求奖励的动机）和喜欢（与奖励消费相关的愉悦）主要由特定脑区的多巴胺能和阿片能活动调节。然而，关于人类奖励加工的多巴胺能和阿片能调节的神经解剖学知之甚少，尤其是在考虑不同类型的奖励（即社会和非社会奖励）时。为了填补这一知识空白，我们结合多巴胺能和阿片能拮抗作用（通过阿米舒必利和纳曲酮给药）和功能神经影像学，使用随机、受试者间、安慰剂对照、双盲设计，研究匹配的非社会（食物）和社会（人际触摸）奖励的想要和喜欢的神经化学和神经解剖基础。虽然在行为水平上没有观察到药物效应，但给予的化合物调节了大脑活动。特别是与安慰剂相比，阿片能拮抗作用在消费最有价值的社会和非社会奖励时，减少了内侧眶额皮质的活动。然而，多巴胺拮抗作用对奖励预期的大脑活动没有明显影响。这些发现为人类奖励加工的神经生物学提供了新的见解，并表明对社会和非社会奖励消费的神经反应存在类似的阿片能调节。
