Sullivan R M, Wilson D A
Department of Psychology, University of Oklahoma, Norman 73019.
Behav Neurosci. 1993 Apr;107(2):254-63. doi: 10.1037//0735-7044.107.2.254.
Although olfactory associative conditioning in newborn rats produces marked structural and functional changes in the olfactory bulb, recent evidence suggests that extrabulbar circuits must be involved in storing these early memories. The present experiments examined the role of the amygdala complex on early olfactory learning. Bilateral amygdala lesions or sham lesions were performed on Postnatal Day (PN) 5. On PN6, pups were trained in a standard classical conditioning paradigm associating odor with tactile stimulation. Behavioral testing on PN7 revealed that amygdala lesions blocked odor preferences but had no effect on conditioned behavioral activation. Similar sized neocortical lesions did not impair odor preferences. Importantly, amygdala lesion effects on learned odor preferences could be reversed by extensive overtraining. These results suggest that the amygdala complex plays a critical role in modulating associative learning as early as the first postnatal week in the rat.
尽管新生大鼠的嗅觉联想性条件反射会在嗅球中产生显著的结构和功能变化，但最近的证据表明，球外回路必定参与了这些早期记忆的存储。本实验研究了杏仁复合体在早期嗅觉学习中的作用。在出生后第5天（PN5）进行双侧杏仁核损伤或假损伤。在PN6时，幼崽在一个将气味与触觉刺激联系起来的标准经典条件反射范式中接受训练。PN7的行为测试表明，杏仁核损伤会阻碍气味偏好，但对条件性行为激活没有影响。类似大小的新皮质损伤不会损害气味偏好。重要的是，通过大量过度训练可以逆转杏仁核损伤对习得气味偏好的影响。这些结果表明，早在大鼠出生后的第一周，杏仁复合体在调节联想学习中就起着关键作用。
