Limbic system

The limbic system is a collection of anatomically and functionally interconnected structures located deep within the cerebrum. It includes both cortical regions—such as the cingulate gyrus and parahippocampal gyrus—and subcortical nuclei like the amygdala, hippocampus, hypothalamus, thalamus (anterior/dorsomedial nuclei), septal nuclei, and olfactory bulb. The primary roles of this network are to process emotions and regulate memory formation. It also influences motivation, learning behaviors such as feeding or reproduction (“survival instincts”), autonomic responses to stress or arousal via connections with endocrine systems, olfaction/sense of smell processing, and behavioral drives. The limbic system is not a single molecule or receptor but rather an anatomical-functional concept encompassing multiple neural circuits. Its components interact through various neurotransmitters—including serotonin from raphe nuclei projections—which modulate emotional states and are targets for psychiatric medications. Dysfunction in these circuits is implicated in neuropsychiatric diseases such as depression or schizophrenia. Because it is not a discrete molecular entity but rather a complex network comprising many different cell types and molecules across several brain regions—and because there is no universal agreement on its exact boundaries—the “limbic system” should not be considered a canonical therapeutic target like an enzyme or receptor. Instead it represents an organizational level above individual molecular targets. The entry "Limbic system" does not correspond to a specific molecule/receptor/therapeutically actionable target; it refers instead to an anatomical-functional network. This makes it incorrect for use where structured information about druggable molecular targets is required.

Other names

Limbic lobelimbic brainpaleomammalian cortex (historical/alternative terms)

Modulation of neurotransmitter signaling in limbic structures (serotonin, dopamine, acetylcholine)