Ishida Hiroaki, Inoue Ken-Ichi, Takada Masahiko
Frontal Lobe Function Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Japan.
Front Neuroanat. 2018 Jan 19;12:3. doi: 10.3389/fnana.2018.00003. eCollection 2018.
The amygdala codes the visual-gustatory/somatosensory valence for feeding behavior. On the other hand, the ventral premotor cortex (PMv) plays a central role in reaching and grasping movements prerequisite for feeding behavior. This implies that object valence signals derived from the amygdala may be crucial for feeding-related motor actions exerted by PMv. However, since no direct connectivity between the amygdala and PMv has been reported, the structural basis of their functional interactions still remains elusive. In the present study, we employed retrograde transneuronal labeling with rabies virus to identify the amygdalar origin and possible route of multisynaptic projections to PMv in macaque monkeys. Histological analysis of the distribution pattern of labeled neurons has found that PMv receives disynaptic input primarily from the basal nucleus, especially from its intermediate subdivision. It has also been revealed that the medial (e.g., the cingulate motor areas, CMA) and lateral (e.g., the insular cortices) cortical areas, and the cholinergic cell group 4 in the basal forebrain probably mediate the projections from the amygdala to PMv. Such multisynaptic pathways might represent amygdalar influences on PMv functions for feeding behavior.
杏仁核编码进食行为的视觉-味觉/躯体感觉效价。另一方面，腹侧运动前皮质（PMv）在进食行为所需的伸手和抓握动作中起核心作用。这意味着来自杏仁核的物体效价信号可能对PMv执行的与进食相关的运动动作至关重要。然而，由于尚未报道杏仁核与PMv之间存在直接连接，它们功能相互作用的结构基础仍然难以捉摸。在本研究中，我们使用狂犬病病毒进行逆行跨神经元标记，以确定猕猴中杏仁核的起源以及向PMv的多突触投射的可能途径。对标记神经元分布模式的组织学分析发现，PMv主要从基底核，特别是其中间亚区接受双突触输入。还发现内侧（如扣带回运动区，CMA）和外侧（如岛叶皮质）皮质区域，以及基底前脑的胆碱能细胞群4可能介导从杏仁核到PMv的投射。这种多突触途径可能代表杏仁核对进食行为中PMv功能的影响。
