Department of Psychiatry, Vanderbilt University Medical School, Nashville, Tennessee, USA.
BMC Neurosci. 2009 Dec 10;10:145. doi: 10.1186/1471-2202-10-145.
Inhibited temperament - the predisposition to respond to new people, places or things with wariness or avoidance behaviors - is associated with increased risk for social anxiety disorder and major depression. Although the magnitude of the amygdala's response to novelty has been identified as a neural substrate of inhibited temperament, there may also be differences in temporal dynamics (latency, duration, and peak). We hypothesized that persons with inhibited temperament would have faster responses to novel relative to familiar neutral faces compared to persons with uninhibited temperament. We used event-related functional magnetic resonance imaging to measure the temporal dynamics of the blood oxygen level dependent (BOLD) response to both novel and familiar neutral faces in participants with inhibited or uninhibited temperament.
Inhibited participants had faster amygdala responses to novel compared with familiar faces, and both longer and greater amygdala response to all faces. There were no differences in peak response.
Faster amygdala response to novelty may reflect a computational bias that leads to greater neophobic responses and represents a mechanism for the development of social anxiety.
抑制气质——对新的人、新的地方或新的事物产生警惕或回避行为的倾向——与社交焦虑障碍和重度抑郁症的风险增加有关。虽然杏仁核对新奇事物的反应程度已被确定为抑制气质的神经基础，但在时间动态（潜伏期、持续时间和峰值）上也可能存在差异。我们假设，与非抑制气质的人相比，具有抑制气质的人对新颖的中性面孔的反应会更快。我们使用事件相关功能磁共振成像来测量具有抑制或非抑制气质的参与者对新颖和熟悉的中性面孔的血氧水平依赖（BOLD）反应的时间动态。
与熟悉的面孔相比，抑制组的参与者对新面孔的杏仁核反应更快，对所有面孔的反应持续时间更长，幅度也更大。在峰值反应方面没有差异。
对新奇事物更快的杏仁核反应可能反映了一种计算偏差，导致更大的恐惧反应，这代表了社交焦虑发展的一种机制。
