volume transmission
A mode of neural communication where neurotransmitters diffuse through extracellular space to reach distant targets.
Full Definition
Volume transmission, also called non-synaptic transmission, occurs when neurotransmitters or neuromodulators are released and diffuse through the extracellular space to influence neurons beyond the immediate synaptic cleft. This mode of communication is slower and more widespread than classical synaptic transmission, often involving modulatory transmitters like dopamine, serotonin, and neuropeptides. Volume transmission plays crucial roles in mood regulation, arousal, and large-scale brain state modulation. The concept appears in literature on neuromodulation, psychiatric disorders, and global brain function.
Usage
Usage note: Distinguish from classical point-to-point synaptic transmission by emphasizing the diffusion aspect.
In Context
- "Dopamine acts primarily through volume transmission to modulate cortical circuits." — Neuromodulation research paper
- "Volume transmission mechanisms may be disrupted in psychiatric disorders." — Clinical neuroscience review