Philippi Carissa L, Mehta Sonya, Grabowski Thomas, Adolphs Ralph, Rudrauf David
Laboratory of Brain Imaging and Cognitive Neuroscience, Department of Neurology, Division of Behavioral Neurology and Cognitive Neuroscience, University of Iowa College of Medicine, Iowa City, Iowa 52242, USA.
J Neurosci. 2009 Dec 2;29(48):15089-99. doi: 10.1523/JNEUROSCI.0796-09.2009.
An array of cortical and subcortical structures have been implicated in the recognition of emotion from facial expressions. It remains unknown how these regions communicate as parts of a system to achieve recognition, but white matter tracts are likely critical to this process. We hypothesized that (1) damage to white matter tracts would be associated with recognition impairment and (2) the degree of disconnection of association fiber tracts [inferior longitudinal fasciculus (ILF) and/or inferior fronto-occipital fasciculus (IFOF)] connecting the visual cortex with emotion-related regions would negatively correlate with recognition performance. One hundred three patients with focal, stable brain lesions mapped onto a reference brain were tested on their recognition of six basic emotional facial expressions. Association fiber tracts from a probabilistic atlas were coregistered to the reference brain. Parameters estimating disconnection were entered in a general linear model to predict emotion recognition impairments, accounting for lesion size and cortical damage. Damage associated with the right IFOF significantly predicted an overall facial emotion recognition impairment and specific impairments for sadness, anger, and fear. One subject had a pure white matter lesion in the location of the right IFOF and ILF. He presented specific, unequivocal emotion recognition impairments. Additional analysis suggested that impairment in fear recognition can result from damage to the IFOF and not the amygdala. Our findings demonstrate the key role of white matter association tracts in the recognition of the facial expression of emotion and identify specific tracts that may be most critical.
一系列皮质和皮质下结构与从面部表情识别情绪有关。目前尚不清楚这些区域作为一个系统的组成部分是如何进行交流以实现识别的，但白质束可能对这一过程至关重要。我们假设：（1）白质束损伤与识别障碍有关；（2）连接视觉皮层与情绪相关区域的联合纤维束[下纵束（ILF）和/或额枕下束（IFOF）]的断开程度与识别表现呈负相关。对103例局灶性、稳定脑损伤且已映射到参考脑的患者进行了六种基本情绪面部表情识别测试。将概率图谱中的联合纤维束与参考脑进行配准。将估计断开程度的参数输入到一般线性模型中，以预测情绪识别障碍，同时考虑病变大小和皮质损伤情况。与右侧IFOF相关的损伤显著预测了整体面部情绪识别障碍以及对悲伤、愤怒和恐惧的特定识别障碍。一名受试者在右侧IFOF和ILF所在位置有单纯的白质病变。他表现出特定的、明确的情绪识别障碍。进一步分析表明，恐惧识别障碍可能是由IFOF损伤而非杏仁核损伤导致的。我们的研究结果证明了白质联合束在面部表情情绪识别中的关键作用，并确定了可能最为关键的特定纤维束。
