Knauth Kilian, Mathar David, Kuzmanovic Bojana, Tittgemeyer Marc, Peters Jan
Department of Psychology, Biological Psychology, University of Cologne, Germany.
Translational Neurocircuitry Group, Max Planck Institute for Metabolism Research Cologne, Cologne, Germany.
Imaging Neurosci (Camb). 2023 Aug 18;1. doi: 10.1162/imag_a_00008. eCollection 2023.
Humans prefer smaller sooner over larger later rewards, a tendency denoted as temporal discounting. Discounting of future rewards is increased in multiple maladaptive behaviors and clinical conditions. Although temporal discounting is stable over time, it is partly under contextual control. Appetitive (erotic) cues might increase preferences for immediate rewards, although evidence to date remains mixed. Reward circuit activity was hypothesized to drive increases in temporal discounting following cue exposure, yet this was never tested directly. We examined erotic vs. neutral cue exposure effects on subsequent temporal discounting in a preregistered within-subjects study in healthy male participants (n = 38). Functional magnetic resonance imaging assessed neural cue-reactivity, value-computations, and choice-related effects. We replicated previous findings of value-coding in ventromedial prefrontal cortices, striatum, and cingulate cortex. Likewise, as hypothesized, lateral prefrontal cortex activity increased during delayed reward choices, potentially reflecting cognitive control. Erotic cue exposure was associated with increased activity in attention and reward circuits. Contrary to preregistered hypotheses, temporal discounting was unaffected by cue exposure, and cue responses in reward circuits did not reliably predict changes in behavior. Our results raise doubts on the hypothesis that upregulation of (dopaminergic) reward systems following erotic cue exposure is sufficient to drive myopic approach behavior towards immediate rewards.
人类更喜欢早一点获得较小的奖励,而不是晚一点获得较大的奖励,这种倾向被称为时间折扣。在多种适应不良行为和临床状况中,对未来奖励的折扣会增加。尽管时间折扣随时间推移是稳定的,但它部分受情境控制。有吸引力的(色情的)线索可能会增加对即时奖励的偏好,不过迄今为止证据仍不一致。有假说认为,线索暴露后奖励回路活动会促使时间折扣增加,但这从未得到直接验证。我们在一项针对健康男性参与者(n = 38)的预先注册的受试者内研究中,考察了色情线索与中性线索暴露对后续时间折扣的影响。功能磁共振成像评估了神经线索反应性、价值计算和与选择相关的效应。我们重复了之前在腹内侧前额叶皮质、纹状体和扣带回皮质中价值编码的研究结果。同样,如所假设的,在延迟奖励选择期间外侧前额叶皮质活动增加,这可能反映了认知控制。色情线索暴露与注意力和奖励回路活动增加有关。与预先注册的假设相反,时间折扣不受线索暴露影响,并且奖励回路中的线索反应并不能可靠地预测行为变化。我们的结果对以下假设提出了质疑:色情线索暴露后(多巴胺能)奖励系统的上调足以驱使对即时奖励的近视趋近行为。