Rashid Maha, Thomas Sarah, Isaac Jennifer, Karkare Sonia Corbett, Klein Hannah, Murugan Malavika
Emory Neuroscience Graduate Program, Emory University, Atlanta, United States.
Department of Biology, Emory University, Atlanta, United States.
Elife. 2025 Jun 4;13:RP97259. doi: 10.7554/eLife.97259.
The ability to distinguish strangers from familiar individuals is crucial for the survival of most mammalian species. In humans, an inability to recognize kin and familiar individuals and engage in appropriate behaviors is associated with several types of dementia, including Alzheimer's disease. Mice preferentially spend more time investigating a novel individual relative to a familiar individual. Yet, how social novelty-related information drives increased investigation of the novel animal remains poorly understood. Recent evidence has implicated the ventral hippocampus (vHPC) as a key node in encoding information about conspecific identity. Of particular interest are vHPC projections to the lateral septum (LS), a region that has been implicated in driving a wide range of motivated social behaviors. In this study using chemogenetics, optogenetics, and monosynaptic rabies tracing, we identified a novel vHPC-LS-ventral tegmental area (VTA) pathway that is necessary for mice to preferentially investigate novel conspecifics. Using monosynaptic rabies tracing, we established that LS neurons make direct monosynaptic connections onto dopaminergic neurons in the VTA. Thus, we have identified a potential pathway via which conspecific identity could be transformed to drive motivated social behaviors.
区分陌生个体和熟悉个体的能力对大多数哺乳动物物种的生存至关重要。在人类中，无法识别亲属和熟悉的个体并进行适当行为与包括阿尔茨海默病在内的几种痴呆症有关。相对于熟悉的个体，小鼠会优先花更多时间去探究陌生个体。然而，与社会新奇性相关的信息如何促使对陌生动物的探究增加，目前仍知之甚少。最近的证据表明腹侧海马体（vHPC）是编码有关同种个体身份信息的关键节点。特别值得关注的是vHPC向外侧隔区（LS）的投射，该区域与驱动广泛的有动机的社会行为有关。在这项使用化学遗传学、光遗传学和单突触狂犬病追踪技术的研究中，我们确定了一条新的vHPC-LS-腹侧被盖区（VTA）通路，这是小鼠优先探究陌生同种个体所必需的。通过单突触狂犬病追踪，我们证实LS神经元与VTA中的多巴胺能神经元形成直接的单突触连接。因此，我们确定了一条潜在的通路，通过该通路同种个体身份信息可以被转化以驱动有动机的社会行为。
