Claude M.J. Braun and Yanick Leblanc-Sirois Pages 266 - 277 ( 12 )
The neuronal synaptic action potential is still considered the basic unit of signaling in the brain underlying mental states, behavior and psychiatric disorders. However, exponentially deepening and mind boggling progress has been made during the last 30 years in the molecular and cellular understanding of what drives action potentials. The classical “synaptic relay model” of the action potential is now considered to be a special, minor case, most relevant to “machine-like” mentation and behavior. Volume transmission, not involving synapses, but certainly driving neuronal action potentials, is now understood to be far more prevalent, complex, and more relevant to “soul-like” mentation and behavior. Only a few very brief or highly technical accounts of this scientific revolution have been published specifically for psychiatrists despite the fact that psychiatry is the discipline most likely to gain in the short term, with neurology following more in the long term. We review here what we think are the most relevant aspects of extrasynaptic signaling for psychiatry in a manner we hope is most useful and enlightening for practicing psychiatrists.
Synaptic signaling, extrasynaptic signaling, wiring transmission, volume transmission, psychiatric disorders, neurological disorders.
Departement de Psychologie, Faculte des Sciences Humaines, Universite du Quebec a Montreal, Montreal, Canada.