A feedback neural circuit for calibrating aversive memory strength
A feedback neural circuit for calibrating aversive memory strength
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DOI：
10.1038/nn.4439
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发表时间：
2017-01-01
影响因子：
25
通讯作者：
Johansen, Joshua P.
中科院分区：
文献类型：
--
作者：
Ozawa, Takaaki;Ycu, Edgar A.;Johansen, Joshua P.
令人厌恶的经历有力地调节了记忆的形成，记忆的强度与这些经历的强度成正比。当传递厌恶信号的神经回路被其他感官刺激预测时，抑制它们被假设为设定联想记忆强度。然而，产生这种预测性抑制以调节记忆形成的神经回路机制尚不清楚。在这里，我们表明，预测性感觉线索从中央杏仁核招募下行反馈回路，激活中脑导水管周围灰色疼痛调节神经元的特定群体来控制厌恶记忆的强度。光遗传抑制该通路的解除抑制预测了储存恐惧记忆的侧杏仁核神经元的厌恶反应，导致恐惧学习水平的重置。这些结果揭示了一种调节学习信号以自适应调节行为学习强度的控制机制。这种神经回路的失调可能导致与恐惧反应增强相关的精神疾病。
Aversive experiences powerfully regulate memory formation, and memory strength is proportional to the intensity of these experiences. Inhibition of the neural circuits that convey aversive signals when they are predicted by other sensory stimuli is hypothesized to set associative memory strength. However, the neural circuit mechanisms that produce this predictive inhibition to regulate memory formation are unknown. Here we show that predictive sensory cues recruit a descending feedback circuit from the central amygdala that activates a specific population of midbrain periaqueductal gray pain-modulatory neurons to control aversive memory strength. Optogenetic inhibition of this pathWay disinhibited predicted aversive responses in lateral amygdala neurons, which store fear memories, resulting in the resetting of fear learning levels. These results reveal a control mechanism for calibrating learning signals to adaptively regulate the strength of behavioral learning. Dysregulation of this circuit could contribute to psychiatric disorders associated with heightened fear responsiveness.