Division of Brain, Imaging and Behaviour - Systems Neuroscience, Toronto Western Research Institute, UHN, University of Toronto, Ontario, Canada.
Brain Stimul. 2012 Apr;5(2):116-23. doi: 10.1016/j.brs.2012.03.007. Epub 2012 Mar 30.
Decision making is a cognitive function relaying on a complex neural network. In particular, the right dorsolateral prefrontal cortex (DLPFC) plays a key role within this network. We used positron emission tomography (PET) combined with continuous theta burst transcranial magnetic stimulation (cTBS) to investigate neuronal and behavioral changes in normal volunteers while performing a delay discounting (DD) task. We aimed to test whether stimulation of right DLPFC would modify the activation pattern of the neural circuit underlying decision making during the DD task and influence discounting behavior. We found that cTBS of the right DLPFC influenced decision making by reducing impulsivity and inducing participants to favor large but delayed rewards instead of immediate but small rewards. Stimulation also affected activation in several prefrontal areas associated with DD. In particular, we observed a reduced regional cerebral blood flow (rCBF) in the ipsilateral DLPFC (BA 46) extending into the rostral part of the prefrontal cortex (BA 10) as well as a disrupted relationship between impulsivity (k-value) and rCBF in these and other prefrontal areas. These findings suggest that transcranial magnetic stimulation of the DLPFC influences the neural network underlying impulsive decision making behavior.
决策是一种依赖于复杂神经网络的认知功能。特别是，右背外侧前额叶皮层（DLPFC）在这个网络中起着关键作用。我们使用正电子发射断层扫描（PET）结合连续 theta 爆发经颅磁刺激（cTBS）来研究正常志愿者在执行延迟折扣（DD）任务时的神经元和行为变化。我们旨在测试刺激右 DLPFC 是否会改变 DD 任务中决策制定的神经回路的激活模式，并影响折扣行为。我们发现，右 DLPFC 的 cTBS 通过降低冲动性并促使参与者倾向于大但延迟的奖励而不是即时但小的奖励，从而影响决策制定。刺激还影响了与 DD 相关的几个前额叶区域的激活。特别是，我们观察到同侧 DLPFC（BA46）的局部脑血流（rCBF）减少，延伸到前额叶的前部（BA10），以及冲动性（k 值）和这些和其他前额叶区域的 rCBF 之间的关系中断。这些发现表明，DLPFC 的经颅磁刺激会影响冲动决策行为的神经网络。
