Solomon P R, Nichols G L, Kiernan J M, Kamer R S, Kaplan L J
J Comp Physiol Psychol. 1980 Feb;94(1):145-54. doi: 10.1037/h0077655.
Rats received either 0 or 30 preexposures to a tone which was later used as a conditioned stimulus (CS) in a two-way avoidance task. Tone preexposure resulted in retarded conditioning in normal animals and animals with dorsal raphe lesions. This latent inhibition effect, however, was not present in animals with medial raphe lesions. The failure of CS preexposure to retard conditioning in animals with medial raphe lesions was not due to differences in auditory sensitivity or shock reactivity. Biochemical analysis indicated that whereas medial raphe lesions significantly reduced serotonin in the septohippocampal complex, dorsal raphe lesions had no such effect. The results are discussed in terms of the differing roles of the mesolimbic and mesostriatal serotonergic systems in learning to ignore irrelevant stimuli.
大鼠接受0次或30次对一种音调的预暴露，该音调后来在双向回避任务中用作条件刺激（CS）。音调预暴露导致正常动物和中缝背核损伤动物的条件反射延迟。然而，这种潜伏抑制效应在中缝内侧核损伤的动物中不存在。中缝内侧核损伤动物中CS预暴露未能延迟条件反射，并非由于听觉敏感性或电击反应性的差异。生化分析表明，中缝内侧核损伤显著降低了隔海马复合体中的5-羟色胺，而中缝背核损伤则没有这种作用。根据中脑边缘和中脑纹状体5-羟色胺能系统在学习忽略无关刺激中的不同作用对结果进行了讨论。
