Department of Psychology, Stanford University, USA.
Department of Neuroscience, Stanford University, USA; Department of Radiology, Stanford University, USA.
Neuroimage. 2014 Aug 1;96:237-44. doi: 10.1016/j.neuroimage.2014.03.073. Epub 2014 Apr 3.
The nucleus accumbens (NAcc) plays critical roles in healthy motivation and learning, as well as in psychiatric disorders (including schizophrenia and attention deficit hyperactivity disorder). Thus, techniques that confer control of NAcc activity might inspire new therapeutic interventions. By providing second-to-second temporal resolution of activity in small subcortical regions, functional magnetic resonance imaging (fMRI) can resolve online changes in NAcc activity, which can then be presented as "neurofeedback." In an fMRI-based neurofeedback experiment designed to elicit NAcc activity, we found that subjects could increase their own NAcc activity, and that display of neurofeedback significantly enhanced their ability to do so. Subjects were not as capable of decreasing their NAcc activity, however, and enhanced control did not persist after subsequent removal of neurofeedback. Further analyses suggested that individuals who recruited positive aroused affect were better able to increase NAcc activity in response to neurofeedback, and that NAcc neurofeedback also elicited functionally correlated activity in the medial prefrontal cortex. Together, these findings suggest that humans can modulate their own NAcc activity and that fMRI-based neurofeedback may augment their efforts. The observed association between positive arousal and effective NAcc control further supports an anticipatory affect account of NAcc function.
伏隔核（NAcc）在健康的动机和学习以及精神疾病（包括精神分裂症和注意缺陷多动障碍）中发挥着关键作用。因此，能够控制 NAcc 活动的技术可能会激发新的治疗干预措施。功能磁共振成像（fMRI）可以提供亚皮质小区域的秒级时间分辨率的活动，从而可以解析 NAcc 活动的在线变化，然后将其表示为“神经反馈”。在一项旨在引起 NAcc 活动的 fMRI 为基础的神经反馈实验中，我们发现受试者可以增加自己的 NAcc 活动，并且神经反馈的显示显著增强了他们这样做的能力。然而，受试者不太能够降低他们的 NAcc 活动，并且在随后去除神经反馈后，增强的控制并没有持续。进一步的分析表明，招募积极唤醒情感的个体能够更好地响应神经反馈增加 NAcc 活动，并且 NAcc 神经反馈还在中前额叶皮层中引起了功能相关的活动。总之，这些发现表明人类可以调节自己的 NAcc 活动，并且基于 fMRI 的神经反馈可以增强他们的努力。观察到的积极唤醒与有效 NAcc 控制之间的关联进一步支持了 NAcc 功能的预期情感解释。
