Falls W A, Davis M
Department of Psychology, Yale University School of Medicine, New Haven., Connecticut 06508, USA.
Behav Neurosci. 1995 Jun;109(3):379-87. doi: 10.1037//0735-7044.109.3.379.
Lesions of the amygdala block the expression of fear-potentiated startle following either moderate or extensive light + shock training. The present experiment assessed whether lesions of the amygdala would also block the expression of conditioned inhibition of fear. Rats were given conditioned inhibition training in which a light was paired with shock and a noise and light compound was presented in the absence of shock. Then half of the rats were given bilateral electrolytic lesions of the amygdala and the remaining rats were sham operated. Lesions of the amygdala blocked the expression of fear-potentiated startle to the light. To assess whether conditioned inhibition was disrupted, rats were retrained with light + shock pairings with no further conditioned inhibition training. Amygdala lesioned rats reacquired fear-potentiated startle to the light (Kim & Davis, 1993). Importantly, the noise conditioned inhibitor retained its ability to inhibit fear-potentiated startle to the retrained light. These results indicate that areas of the amygdala critical for initial performance of fear-potentiated startle are not critical for the expression of conditioned inhibition.
在经历适度或广泛的光照+电击训练后，杏仁核损伤会阻断恐惧增强型惊吓反应的表现。本实验评估了杏仁核损伤是否也会阻断恐惧的条件性抑制表现。对大鼠进行条件性抑制训练，在此训练中，将光照与电击配对，并在无电击的情况下呈现噪声和光照复合刺激。然后，对一半的大鼠进行双侧杏仁核电解损伤，其余大鼠进行假手术。杏仁核损伤阻断了对光照的恐惧增强型惊吓反应的表现。为了评估条件性抑制是否被破坏，对大鼠重新进行光照+电击配对训练，不再进行进一步的条件性抑制训练。杏仁核损伤的大鼠重新获得了对光照的恐惧增强型惊吓反应（Kim和Davis，1993）。重要的是，噪声条件性抑制剂保留了其抑制对重新训练的光照产生恐惧增强型惊吓反应的能力。这些结果表明，对恐惧增强型惊吓反应的初始表现至关重要的杏仁核区域，对条件性抑制的表现并不关键。
