探索和防御行为之间的适当平衡对于在危险环境中猎物的生存和繁殖至关重要。然而,允许这种平衡的神经回路和机制仍然知之甚少。这里,我们使用半自然主义捕食者威胁测试(PTT)来观察和量化防御-探索平衡,尤其是老鼠的风险探索行为。在PTT期间,假定的背侧CA3谷氨酸能神经元(dCA3Glu)的活性受到掠夺性威胁和风险探索的抑制,而神经元在上下文探索期间被激活。此外,这些神经元的光遗传学激发诱导了风险探索的显着增加。一个电路,包括背侧CA3,背侧外侧间隔,和背侧下丘脑(dCA3Glu-dLSGABA-DMH)区,可能涉及。此外,dCA3Glu-dLSGABA-DMH电路的激活可促进从防御到风险探索的转变,并抑制威胁引起的唤醒增加。
An appropriate balance between explorative and defensive behavior is essential for the survival and reproduction of prey animals in risky environments. However, the neural circuit and mechanism that allow for such a balance remains poorly understood. Here, we use a semi-naturalistic predator threat test (PTT) to observe and quantify the defense-exploration balance, especially risk exploration behavior in mice. During the PTT, the activity of the putative dorsal CA3 glutamatergic neurons (dCA3Glu) is suppressed by predatory threat and risk exploration, whereas the neurons are activated during contextual exploration. Moreover, optogenetic excitation of these neurons induces a significant increase in risk exploration. A circuit, comprising the dorsal CA3, dorsal lateral septal, and dorsomedial hypothalamic (dCA3Glu-dLSGABA-DMH) areas, may be involved. Moreover, activation of the dCA3Glu-dLSGABA-DMH circuit promotes the switch from defense to risk exploration and suppresses threat-induced increase in arousal.