Neuroscience Graduate Program, University of California, San Diego, CA, USA.
Cereb Cortex. 2013 Oct;23(10):2479-88. doi: 10.1093/cercor/bhs245. Epub 2012 Aug 9.
Preparing to stop an inappropriate action requires keeping in mind the task goal and using this to influence the action control system. We tested the hypothesis that different subregions of prefrontal cortex show different temporal profiles consistent with dissociable contributions to preparing-to-stop, with dorsolateral prefrontal cortex (DLPFC) representing the task goal and ventrolateral prefrontal cortex (VLPFC) implementing action control. Five human subjects were studied using electrocorticography recorded from subdural grids over right lateral frontal cortex. On each trial, a task cue instructed the subject whether stopping might be needed or not (Maybe Stop [MS] or No Stop [NS]), followed by a go cue, and on some MS trials, a subsequent stop signal. We focused on go trials, comparing MS with NS. In the DLPFC, most subjects had an increase in high gamma activity following the task cue and the go cue. In contrast, in the VLPFC, all subjects had activity after the go cue near the time of the motor response on MS trials, related to behavioral slowing, and significantly later than the DLPFC activity. These different temporal profiles suggest that DLPFC and VLPFC could have dissociable roles, with DLPFC representing task goals and VLPFC implementing action control.
准备停止不适当的行为需要记住任务目标,并利用目标来影响动作控制系统。我们测试了这样一个假设,即前额叶皮层的不同子区域表现出不同的时间模式,这与为准备停止而进行的可分离贡献一致,其中背外侧前额叶皮层(DLPFC)代表任务目标,腹外侧前额叶皮层(VLPFC)则执行动作控制。我们使用记录自右外侧额皮质的硬膜下网格的脑电描记术研究了五名人类受试者。在每次试验中,任务提示会指示受试者是否需要停止(可能停止[MS]或不停止[NS]),然后是前进提示,并且在一些 MS 试验中,会有后续的停止信号。我们专注于前进试验,将 MS 与 NS 进行比较。在 DLPFC 中,大多数受试者在任务提示和前进提示后会增加高伽马活动。相比之下,在 VLPFC 中,所有受试者在 MS 试验上的运动反应附近的前进提示后都会有活动,这与行为减速有关,并且比 DLPFC 的活动晚得多。这些不同的时间模式表明,DLPFC 和 VLPFC 可能具有可分离的作用,DLPFC 代表任务目标,而 VLPFC 则执行动作控制。