Department of Psychology, Michigan State University, East Lansing, Michigan 48824, USA.
Neuroscience Program, Michigan State University, East Lansing, Michigan 48824, USA.
Learn Mem. 2021 Mar 15;28(4):104-108. doi: 10.1101/lm.053082.120. Print 2021 Apr.
The dopamine system has been implicated in decision-making particularly when associated with effortful behavior. We examined acute optogenetic stimulation of dopamine cells in the ventral tegmental area (VTA) as mice engaged in an effort-based decision-making task. Tyrosine hydroxylase-Cre mice were injected with Cre-dependent ChR2 or eYFP control virus in the VTA. While eYFP control mice showed effortful discounting, stimulation of dopamine cells in ChR2 mice disrupted effort-based decision-making by reducing choice toward the lever associated with a preferred outcome and greater effort. Surprisingly, disruptions in effortful discounting were observed in subsequent test sessions conducted in the absence of optogenetic stimulation, however during these sessions ChR2 mice displayed enhanced high choice responding across trial blocks. These findings suggest increases in VTA dopamine cell activity can disrupt effort-based decision-making in distinct ways dependent on the timing of optogenetic stimulation.
多巴胺系统与费力行为相关，被认为参与了决策过程。我们在小鼠进行基于努力的决策任务时，观察了腹侧被盖区（VTA）中多巴胺细胞的急性光遗传学刺激。酪氨酸羟化酶-Cre 小鼠在 VTA 中注射了 Cre 依赖性 ChR2 或 eYFP 对照病毒。在 eYFP 对照小鼠中，费力折扣出现，而 ChR2 小鼠的多巴胺细胞刺激通过减少与偏好结果相关的杠杆的选择以及更大的努力，破坏了基于努力的决策。令人惊讶的是，在没有光遗传学刺激的后续测试中观察到费力折扣的破坏，但在这些测试中，ChR2 小鼠在整个试验块中显示出增强的高选择反应。这些发现表明，VTA 多巴胺细胞活动的增加可以以依赖于光遗传学刺激时间的不同方式破坏基于努力的决策。
