Hillary Frank G
Department of Psychology, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
J Int Neuropsychol Soc. 2008 Jul;14(4):526-34. doi: 10.1017/S1355617708080788.
There is a growing literature examining working memory deficits using functional imaging and there has been great convergence in the findings, to date, but interpretations have varied. Investigators consistently observed recruitment of neural resources in clinical samples, with some examiners attributing these findings to neural inefficiency and others attributing differences to neural compensation and/or brain reorganization. It is the goal of this paper to address the current interpretation of altered brain activation in clinical imaging studies of working memory dysfunction with specific emphasis on findings in prefrontal cortex (PFC). Throughout this review, the methods used to examine brain reorganization associated with working memory dysfunction are critiqued with the goal of understanding how study design has influenced data interpretation. It is proposed that much of what has been considered "aberrant" neural activity is not indicative of neural compensation, as it has been typically defined, and does not represent brain reorganization. Instead, recruitment of neural resources in PFC can be explained by a natural, and largely overlooked, role of cognitive control in accommodating neural dysfunction secondary to brain injury and disease. This paper provides predictions based on this proposition and a critique of the current methods available for testing these predictions.
有越来越多的文献利用功能成像研究工作记忆缺陷，迄今为止研究结果已高度趋同，但解读却各不相同。研究人员在临床样本中始终观察到神经资源的募集，一些研究者将这些发现归因于神经效率低下，而另一些人则将差异归因于神经补偿和/或大脑重组。本文的目的是探讨工作记忆功能障碍临床成像研究中大脑激活改变的当前解读，特别强调前额叶皮质（PFC）的研究结果。在这篇综述中，对用于研究与工作记忆功能障碍相关的大脑重组的方法进行了批判，目的是了解研究设计如何影响数据解读。有人提出，许多被认为是“异常”的神经活动并不像通常所定义的那样表明神经补偿，也不代表大脑重组。相反，前额叶皮质中神经资源的募集可以用认知控制在适应继发于脑损伤和疾病的神经功能障碍方面的自然但很大程度上被忽视的作用来解释。本文基于这一命题提供了预测，并对目前可用于检验这些预测的方法进行了批判。
