Department of Cognitive Psychology, Institute for Psychology, University of Hamburg, Hamburg, Germany.
Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.
Sci Rep. 2018 Jun 20;8(1):9382. doi: 10.1038/s41598-018-27678-6.
Successful adaptation to complex environments depends on the balance of at least two systems: a flexible but slow goal-directed system encoding action-outcome associations and an efficient but rigid habitual system linking responses to preceding stimuli. Recent evidence suggests that the inferolateral prefrontal cortex (ilPFC), a region well known to contribute to cognitive control processes, may play a crucial role in the balance of goal-directed and habitual responding. This evidence, however, comes mainly from correlational data and whether the ilPFC is indeed causally involved in the goal-directed vs. habitual control of behavior is unclear. Here, we used neuro-navigated theta-burst stimulation (TBS) to either inhibit or enhance right ilPFC functionality before participants completed an instrumental learning task designed to probe goal-directed vs. habitual behavioral control. TBS did not affect overall learning performance. However, participants that had received inhibitory TBS were less able to adapt their behavior to altered task demands, indicating a shift from goal-directed towards more habitual control of behavior. Sham or excitatory TMS groups showed no such effect and were comparable in their performance to an unstimulated control group. Our findings indicate a causal role of the ilPFC in the balance of goal-directed vs. habitual control of behavior.
一个灵活但缓慢的目标导向系统，用于编码动作-结果关联；一个高效但僵化的习惯系统，用于将反应与先前的刺激联系起来。最近的证据表明，外侧前额叶皮层（ilPFC），一个已知对认知控制过程有贡献的区域，可能在目标导向和习惯反应的平衡中发挥关键作用。然而，这些证据主要来自相关数据，并且 ilPFC 是否确实涉及目标导向与习惯行为控制的因果关系尚不清楚。在这里，我们使用神经导航的 theta 爆发刺激（TBS）在参与者完成旨在探测目标导向与习惯行为控制的仪器学习任务之前，抑制或增强右侧 ilPFC 的功能。TBS 不会影响整体学习表现。然而，接受抑制性 TBS 的参与者在适应任务需求变化方面的能力下降，表明行为从目标导向向更习惯的控制转变。假刺激或兴奋性 TMS 组没有表现出这种影响，并且与未经刺激的对照组的表现相当。我们的发现表明 ilPFC 在目标导向与习惯控制行为的平衡中起着因果作用。
