Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405, USA.
Neuropsychologia. 2010 Jan;48(2):558-65. doi: 10.1016/j.neuropsychologia.2009.10.017. Epub 2009 Oct 29.
A growing number of studies have investigated how motivation interacts with particular cognitive functions, including attention, working memory, and other executive functions. In these studies, the emphasis has been on understanding how motivation impacts brain regions that contribute to improving behavioral performance. Less is understood about how positive incentives may actually impair behavioral performance. Here, we were interested in investigating a situation in which reward would be potentially deleterious to behavioral performance. Specifically, we hypothesized that rewarding participants for correct going would impair stopping performance. Critically, we hypothesized that the effects on inhibition would be specific, namely, not simply attributable to a speeding-up of reaction time during go trials. To investigate the interaction between inhibition and motivation, participants performed a stop-signal task during two conditions, namely, during a neutral, control condition and during a rewarded condition during which they were rewarded for correct go performance. Behaviorally, participants exhibited longer stop-signal reaction times during the reward relative to the control condition, indicating that it was harder to inhibit their responses during the former condition. Neuroimaging findings revealed that a host of brain regions were involved in stop-signal inhibition, as indexed via the contrast of successful and unsuccessful stop trials. Critically, a subset of these regions, which included the right inferior frontal gyrus, the left precentral gyrus, and bilateral putamen, exhibited significant inhibition by condition interactions, demonstrating that cognitive and motivational signals interact in the brain during inhibitory control.
越来越多的研究调查了动机如何与特定的认知功能相互作用，包括注意力、工作记忆和其他执行功能。在这些研究中，重点是理解动机如何影响有助于提高行为表现的大脑区域。对于积极的激励因素如何实际上可能损害行为表现，人们的了解较少。在这里，我们有兴趣研究一种情况，即奖励可能对行为表现有害。具体来说，我们假设奖励参与者正确的“走”会损害他们的“停”的表现。关键的是，我们假设抑制的影响是特定的，即不仅仅归因于在“走”试次中反应时间的加快。为了研究抑制和动机之间的相互作用，参与者在两种条件下执行停止信号任务，即中性控制条件和奖励条件，在奖励条件下，他们因正确的“走”表现而获得奖励。行为上，与控制条件相比，参与者在奖励条件下表现出更长的停止信号反应时间，这表明在前一种条件下抑制反应更加困难。神经影像学研究结果表明，一系列大脑区域参与了停止信号抑制，这可以通过成功和不成功的停止试次的对比来衡量。关键的是，这些区域中的一部分，包括右额下回、左中央前回和双侧壳核，表现出显著的抑制条件相互作用，表明在抑制控制过程中，认知和动机信号在大脑中相互作用。
