Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands.
Klinik Für Psychiatrie, Sozialpsychiatrie Und Psychotherapie, Medizinische Hochschule Hannover, Hannover, Germany.
Sci Rep. 2021 Feb 23;11(1):4399. doi: 10.1038/s41598-021-82902-0.
Previous studies have not clearly demonstrated whether motivational tendencies during reward feedback are mainly characterized by appetitive responses to a gain or mainly by aversive consequences of reward omission. In the current study this issue was addressed employing a passive head or tails game and using the startle reflex as an index of the appetitive-aversive continuum. A second aim of the current study was to use startle-reflex modulation as a means to compare the subjective value of monetary rewards of varying magnitude. Startle responses after receiving feedback that a potential reward was won or not won were compared with a baseline condition without a potential gain. Furthermore, startle responses during anticipation of no versus potential gain were compared. Consistent with previous studies, startle-reflex magnitudes were significantly potentiated when participants anticipated a reward compared to no reward, which may reflect anticipatory arousal. Specifically for the largest reward (20-cents) startle magnitudes were potentiated when a reward was at stake but not won, compared to a neutral baseline without potential gain. In contrast, startle was not inhibited relative to baseline when a reward was won. This suggests that startle modulation during feedback is better characterized in terms of potentiation when missing out on reward rather than in terms of inhibition as a result of winning. However, neither of these effects were replicated in a more targeted second experiment. The discrepancy between these experiments may be due to differences in motivation to obtain rewards or differences in task engagement. From these experiments it may be concluded that the nature of the processing of reward feedback and reward cues is very sensitive to experimental parameters and settings. These studies show how apparently modest changes in these parameters and settings may lead to quite different modulations of appetitive/aversive motivation. A future experiment may shed more light on the question whether startle-reflex modulation after feedback is indeed mainly characterized by the aversive consequences of reward omission for relatively large rewards.
先前的研究并未明确表明，在奖励反馈期间，动机倾向主要是以对收益的渴望反应为特征，还是主要以奖励缺失的厌恶后果为特征。在当前的研究中，通过使用被动的头或尾游戏，并使用惊跳反射作为食欲-厌恶连续体的指标，解决了这个问题。当前研究的第二个目的是使用惊跳反射调制作为比较不同大小的货币奖励的主观价值的一种手段。将收到反馈表明潜在奖励已获得或未获得后的惊跳反应与没有潜在收益的基线条件进行比较。此外，还比较了在没有潜在收益的情况下预期收益与没有预期收益时的惊跳反射。与先前的研究一致，当参与者预期获得奖励而不是没有奖励时，惊跳反射幅度明显增强，这可能反映了预期的唤醒。特别是对于最大的奖励（20 美分），当面临奖励但未获胜时，惊跳幅度相对于没有潜在收益的中性基线增强。相比之下，当赢得奖励时，惊跳不会相对于基线受到抑制。这表明，在反馈期间，惊跳调制更好地用错过奖励的增强来描述，而不是用赢得奖励的抑制来描述。但是，在更有针对性的第二个实验中，这些效应都没有得到复制。这些实验之间的差异可能归因于获得奖励的动机差异或任务参与度的差异。从这些实验中可以得出结论，奖励反馈和奖励线索的处理性质对实验参数和设置非常敏感。这些研究表明，这些参数和设置的微小变化可能导致食欲-厌恶动机的截然不同的调制。未来的实验可能会进一步阐明反馈后惊跳反射调制是否确实主要以相对较大奖励的奖励缺失的厌恶后果为特征的问题。
