Department of Psychosomatic Medicine and Psychotherapy, University of Leipzig, Semmelweisstrasse 10, 04103 Leipzig, Germany.
BMC Neurosci. 2014 Mar 14;15:40. doi: 10.1186/1471-2202-15-40.
Alexithymia is a personality trait that is characterized by difficulties in identifying and describing feelings. Previous studies have shown that alexithymia is related to problems in recognizing others' emotional facial expressions when these are presented with temporal constraints. These problems can be less severe when the expressions are visible for a relatively long time. Because the neural correlates of these recognition deficits are still relatively unexplored, we investigated the labeling of facial emotions and brain responses to facial emotions as a function of alexithymia.
Forty-eight healthy participants had to label the emotional expression (angry, fearful, happy, or neutral) of faces presented for 1 or 3 seconds in a forced-choice format while undergoing functional magnetic resonance imaging. The participants' level of alexithymia was assessed using self-report and interview. In light of the previous findings, we focused our analysis on the alexithymia component of difficulties in describing feelings. Difficulties describing feelings, as assessed by the interview, were associated with increased reaction times for negative (i.e., angry and fearful) faces, but not with labeling accuracy. Moreover, individuals with higher alexithymia showed increased brain activation in the somatosensory cortex and supplementary motor area (SMA) in response to angry and fearful faces. These cortical areas are known to be involved in the simulation of the bodily (motor and somatosensory) components of facial emotions.
The present data indicate that alexithymic individuals may use information related to bodily actions rather than affective states to understand the facial expressions of other persons.
述情障碍是一种人格特质，其特征是难以识别和描述情感。先前的研究表明，述情障碍与在时间限制下识别他人情绪面部表情的问题有关。当表情可见时间相对较长时，这些问题可能不太严重。由于这些识别缺陷的神经相关性仍相对未知，我们研究了述情障碍与面部表情标签和大脑对情绪面部表情的反应之间的关系。
48 名健康参与者在功能磁共振成像过程中需要在强制选择格式下对呈现 1 秒或 3 秒的面部表情（愤怒、恐惧、快乐或中性）进行标签。参与者的述情障碍水平通过自我报告和访谈进行评估。鉴于先前的发现，我们的分析重点是描述感受困难的述情障碍成分。访谈评估的描述感受困难与负面（即愤怒和恐惧）面孔的反应时间延长有关，但与标签准确性无关。此外，述情障碍程度较高的个体在对愤怒和恐惧的面孔作出反应时，大脑体感皮层和补充运动区（SMA）的激活增加。这些皮层区域已知与面部情绪的身体（运动和体感）成分的模拟有关。
本研究数据表明，述情障碍个体可能使用与身体动作相关的信息，而不是情感状态来理解他人的面部表情。
