Brain Dynamics and Cognition, INSERM U, Lyon, France.
Hum Brain Mapp. 2010 Aug;31(8):1217-32. doi: 10.1002/hbm.20930.
Evaluating the outcome of our own actions is a fundamental process by which we adapt our behavior in our interaction with the external world. fMRI and electrophysiological studies in monkeys have found feedback-specific responses in several brain regions, unveiling facets of a large-scale network predominantly distributed in the frontal lobes. However, a consensus has yet to be reached regarding the exact contribution of each region. The present study benefited from intracerebral EEG recordings in epileptic patients to record directly the neural activity in each of those frontal structures in response to positive and negative feedback. Both types of feedback induced a sequence of high-frequency responses (>40 Hz) in a widespread network involving medial frontal cortex, dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC), and insular cortex. The pre-supplementary motor area (pre-SMA), DLPFC, and lateral OFC showed higher activation in response to negative feedback, while medial OFC and dorsal anterior cingulate cortex (dACC) were more responsive to positive feedback. Responses in the medial prefrontal cortex (pre-SMA and dACC) were sustained (lasting more than 1,000 ms), while responses in the DLPFC, insula, and the OFC were short lasting (less than 800 ms). Taken together, our findings show that evaluating the outcome of our actions triggers gamma-range activity modulations in several frontal and insular regions. Moreover, we found that the timing and amplitude of those gamma-band responses reveal fine-scale dissociations between the neural dynamics of positive versus negative feedback processing.
评估我们自身行为的结果是我们在与外部世界互动中调整行为的基本过程。在猴子的 fMRI 和电生理研究中,在几个脑区发现了与反馈相关的特异性反应,揭示了一个主要分布在额叶的大规模网络的各个方面。然而,对于每个区域的确切贡献还没有达成共识。本研究受益于癫痫患者的颅内 EEG 记录,以直接记录这些额叶结构在正负反馈下的神经活动。这两种类型的反馈都在一个涉及内侧前额叶皮层、背外侧前额叶皮层(DLPFC)、眶额皮层(OFC)和岛叶的广泛网络中引发了一系列高频反应(>40 Hz)。与负反馈相比,前补充运动区(pre-SMA)、DLPFC 和外侧 OFC 的激活更高,而内侧 OFC 和背侧前扣带皮层(dACC)对正反馈的反应更敏感。内侧前额叶皮层(pre-SMA 和 dACC)的反应持续时间较长(超过 1000 毫秒),而 DLPFC、岛叶和 OFC 的反应持续时间较短(少于 800 毫秒)。总的来说,我们的研究结果表明,评估我们行为的结果会触发几个额叶和岛叶区域的伽马波段活动调制。此外,我们发现,这些伽马波段反应的时间和幅度揭示了正负反馈处理的神经动力学之间的精细差异。