Schanbacher A, Koch M, Pilz P K, Schnitzler H U
Universität Tübingen, Germany.
Physiol Behav. 1996 Nov;60(5):1341-6. doi: 10.1016/s0031-9384(96)00242-9.
The acoustic startle response (ASR) is enhanced in the presence of loud background noise. We examined whether or not this increase of response strength is mediated by the amygdala, which is known to be involved in various phenomena of enhancement of the ASR. To achieve this aim, we tested whether or not amygdaloid lesions with the excitotoxin N-methyl-D-aspartate (NMDA) would abolish the enhancement of the ASR by background noise in 13 Wistar rats. Loss of foot-shock sensitization in these rats, as well as histological evaluation, proved the successful destruction of the amygdala. However, the enhancement by background noise of the ASR, which was observed in sham-operated controls, was not affected in amygdala-lesioned rats. Therefore, we conclude that the background noise facilitation does not involve emotional components that are mediated by the amygdala. On the basis of these findings, we differentiate between the startle-enhancing effect of background noise and the amygdala-mediated effect of foot shocks on the ASR.
在存在响亮背景噪音的情况下，听觉惊吓反应（ASR）会增强。我们研究了这种反应强度的增加是否由杏仁核介导，已知杏仁核参与ASR增强的各种现象。为实现这一目标，我们测试了用兴奋性毒素N-甲基-D-天冬氨酸（NMDA）造成的杏仁核损伤是否会消除13只Wistar大鼠中背景噪音对ASR的增强作用。这些大鼠足部电击敏化的丧失以及组织学评估证明杏仁核已被成功破坏。然而，在假手术对照组中观察到的背景噪音对ASR的增强作用在杏仁核损伤的大鼠中并未受到影响。因此，我们得出结论，背景噪音促进作用不涉及由杏仁核介导的情绪成分。基于这些发现，我们区分了背景噪音对惊吓反应的增强作用和足部电击对ASR的杏仁核介导作用。
