Parr Ashley C, Coe Brian C, Munoz Douglas P, Dorris Michael C
Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.
Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania.
Eur J Neurosci. 2020 May;51(9):1914-1927. doi: 10.1111/ejn.14586. Epub 2019 Oct 29.
During competitive interactions, such as predator-prey or team sports, the outcome of one's actions is dependent on both their own choices and those of their opponents. Success in these rivalries requires that individuals choose dynamically and unpredictably, often adopting a mixed strategy. Understanding the neural basis of strategic decision making is complicated by the fact that it recruits various cognitive processes that are often shared with non-strategic forms of decision making, such as value estimation, working memory, response inhibition, response selection, and reward processes. Although researchers have explored neural activity within key brain regions during mixed-strategy games, how brain activity differs in the context of strategic interactions versus non-strategic choices is not well understood. We developed a novel behavioral paradigm to dissociate choice behavior during mixed-strategy interactions from non-strategic choices, and we used task-based functional magnetic resonance imaging (fMRI) to contrast brain activation. In a block design, participants competed in the classic mixed-strategy game, "matching pennies," against a dynamic computer opponent designed to exploit predictability in players' response patterns. Results were contrasted with a non-strategic task that had comparable sensory input, motor output, and reward rate; thus, differences in behavior and brain activation reflect strategic processes. The mixed-strategy game was associated with activation of a distributed cortico-striatal network compared to the non-strategic task. We propose that choosing in mixed-strategy contexts requires additional cognitive demands present to a lesser degree during the control task, illustrating the strength of this design in probing function of cognitive systems beyond core sensory, motor, and reward processes.
在竞争性互动中，比如捕食者与猎物的关系或团队运动，一个人行动的结果既取决于他们自己的选择，也取决于对手的选择。在这些竞争中取得成功需要个体动态且不可预测地做出选择，通常采用混合策略。理解战略决策的神经基础很复杂，因为它涉及各种认知过程，而这些过程往往与非战略形式的决策所共有的，如价值估计、工作记忆、反应抑制、反应选择和奖励过程。尽管研究人员已经探索了混合策略游戏中关键脑区的神经活动，但在战略互动与非战略选择的背景下大脑活动如何不同，目前还不太清楚。我们开发了一种新颖的行为范式，以区分混合策略互动中的选择行为与非战略选择，并且我们使用基于任务的功能磁共振成像（fMRI）来对比大脑激活情况。在一个组块设计中，参与者与一个动态计算机对手进行经典的混合策略游戏“猜硬币”，该对手旨在利用玩家反应模式中的可预测性。结果与一个具有可比感官输入、运动输出和奖励率的非战略任务进行对比；因此，行为和大脑激活的差异反映了战略过程。与非战略任务相比，混合策略游戏与一个分布式皮质 - 纹状体网络的激活有关。我们提出，在混合策略背景下做出选择需要在控制任务中程度较低地呈现的额外认知需求，这说明了这种设计在探究核心感官、运动和奖励过程之外的认知系统功能方面的优势。
