Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA.
Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA.
Cell. 2014 Sep 25;159(1):21-32. doi: 10.1016/j.cell.2014.08.037.
Behavioral choices that ignore prior experience promote exploration and unpredictability but are seemingly at odds with the brain's tendency to use experience to optimize behavioral choice. Indeed, when faced with virtual competitors, primates resort to strategic counter prediction rather than to stochastic choice. Here, we show that rats also use history- and model-based strategies when faced with similar competitors but can switch to a "stochastic" mode when challenged with a competitor that they cannot defeat by counter prediction. In this mode, outcomes associated with an animal's actions are ignored, and normal engagement of anterior cingulate cortex (ACC) is suppressed. Using circuit perturbations in transgenic rats, we demonstrate that switching between strategic and stochastic behavioral modes is controlled by locus coeruleus input into ACC. Our findings suggest that, under conditions of uncertainty about environmental rules, changes in noradrenergic input alter ACC output and prevent erroneous beliefs from guiding decisions, thus enabling behavioral variation. PAPERCLIP:
忽略先前经验的行为选择可以促进探索和不可预测性，但似乎与大脑利用经验来优化行为选择的趋势相悖。事实上，当面对虚拟竞争对手时，灵长类动物会采取策略性的反预测，而不是随机选择。在这里，我们发现，当面对类似的竞争对手时，老鼠也会使用基于历史和模型的策略，但当面对一个无法通过反预测击败的竞争对手时，它们可以切换到“随机”模式。在这种模式下，与动物行为相关的结果被忽略，而扣带前皮质（ACC）的正常参与被抑制。使用转基因大鼠的电路干扰，我们证明了策略和随机行为模式之间的切换是由蓝斑核输入到 ACC 控制的。我们的研究结果表明，在环境规则不确定的情况下，去甲肾上腺素能输入的变化会改变 ACC 的输出，防止错误的信念指导决策，从而促进行为变化。
