在听觉恐惧条件反射之前而非之后使杏仁核功能失活可阻止记忆形成。
Functional inactivation of the amygdala before but not after auditory fear conditioning prevents memory formation.
作者信息
Wilensky A E, Schafe G E, LeDoux J E
机构信息
W. M. Keck Foundation Laboratory of Neurobiology, Center for Neural Science, New York University, New York, New York 10003, USA.
出版信息
J Neurosci. 1999 Dec 15;19(24):RC48. doi: 10.1523/JNEUROSCI.19-24-j0006.1999.
Two competing theories predict different effects on memory consolidation when the amygdala is inactivated after fear conditioning. One theory, based on studies using inhibitory avoidance training, proposes that the amygdala modulates the strength of fear learning, and post-training amygdala manipulations interfere with memory consolidation. The other, based on studies using Pavlovian fear conditioning, hypothesizes that fear learning occurs in the amygdala, and post-training manipulations after acquisition will not affect memory consolidation. We infused the GABAA agonist muscimol (4.4 nmol/side) or vehicle into lateral and basal amygdala (LBA) of rats either before or immediately after tone-foot shock Pavlovian fear conditioning. Pre-training infusions eliminated acquisition, whereas post-training infusions had no effect. These findings indicate that synaptic activity in LBA is necessary during learning, but that amygdala inactivation directly after training does not affect memory consolidation. Results suggest that essential aspects of plasticity underlying auditory fear conditioning take place within LBA during learning.
两种相互竞争的理论预测,在恐惧条件反射后杏仁核失活时,对记忆巩固会产生不同影响。一种基于使用抑制性回避训练的研究的理论提出,杏仁核调节恐惧学习的强度,训练后对杏仁核的操作会干扰记忆巩固。另一种基于使用巴甫洛夫恐惧条件反射的研究的理论假设,恐惧学习发生在杏仁核中,习得后训练后的操作不会影响记忆巩固。我们在大鼠进行纯音-足部电击巴甫洛夫恐惧条件反射之前或之后,立即将GABAA激动剂蝇蕈醇(4.4纳摩尔/侧)或赋形剂注入大鼠的外侧和基底杏仁核(LBA)。训练前注入会消除习得,而训练后注入则没有效果。这些发现表明,学习过程中LBA的突触活动是必要的,但训练后立即使杏仁核失活不会影响记忆巩固。结果表明,听觉恐惧条件反射背后可塑性的基本方面在学习过程中发生在LBA内。