If the nomenclature is wrong the action may be wrong!

Having practised orthomolecular psychiatry as an integral part of functional medicine for the past twenty seven years out of thirty and currently finishing off a new book "The Treatment & Prevention of Stroke & Dementia' and just researching the latest info on the physiology of the brain, I was not all that surprised to find:

If the nomenclature is wrong, then the action may be wrong!

In the past, neurons were the source of everything associated with the mind/brain complex and consequently all treatment was focussed on the neurons hence the terminology “Neurology”. The grey white matter of the brain is made up of glia, which were understood to support neurons; to feed them and clean up after them, and to respond to brain injury. But these functions were regarded as peripheral to the exciting functions that neurons perform in processing information and storing memories. All of this thought system has been changed, they had it wrong!

Glia make up about 85% of the brain and the functions of glia can be broadly divided into three main categories consisting of four very different types of glia which serve these different functions.
Astrocytes are glia so named because their shape reminded early anatomists of stars, fill the spaces between neurons. Astrocytes provide the energy source to neurons; they maintain the chemical environment surrounding neurons within the narrow limits required for neurons to survive and fire electrical impulses, and to communicate at synapses.

Microglia are the immune cells of the brain. The brain is isolated from the rest of the fluids in the body because the unique environment within brain tissue must be maintained. A barrier between the brain and the blood is formed by cells in the walls of blood vessels in the brain, which prevents the free diffusion of materials and cells between blood and brain. However, this barrier also prevents the immune cells of the bloodstream, which protect the entire body, from entering the brain. Microglia are the brain’s private cellular guard cells, seeking out and killing germs and healing the brain after injury. As such, microglia are involved in every aspect of nervous system disease and healing.

The third important function of glia is to form the electrical insulation on nerve fibres (axons), which is essential for high speed transmission of electrical impulses. The importance of this insulation, called myelin, is clearly seen in people who suffer from multiple sclerosis, an autoimmune disorder that attacks the myelin sheath on axons, which leaves these people with serious impairments in sensory and motor function. Inside the brain and spinal cord, glial cells resembling cellular octopuses wrap up to 150 layers of compacted membrane around axons, much like electrical tape. The core of the brain—half its bulk—is comprised of millions of tightly bundled axons insulated with myelin. This brain region is called "white matter," because the colour of myelin tints this brain tissue white. Although of little interest in the past, white matter is the newest area of research on learning. In the rest of the body, glial called Schwann cells, which resemble flattened pearls strung up on axons, form this vital insulation.

As for role of astrocytes in forming synapses and changing their strength, and in how astrocytes communicate with each other and with neurons, we are only beginning to understand how astrocytes develop, grow, change forms, and respond to neurons. Astrocytes do, however, communicate among themselves with chemical signalling. This signalling can be observed using fluorescent dyes that sense calcium levels inside the cells.

Astrocytes have receptors for neuron transmitters, enabling them to respond to the neurotransmitter released by neurons at synapses. Astrocytes can communicate with other astrocytes, and they release or take up neurotransmitters from distant synapses to control the transmission of information between neurons.

The activity of astrocytes in controlling neurotransmitter levels at synapses implicates them in psychiatric disorders. All drugs for treating mental illnesses act by controlling the levels of different neurotransmitters, but this is the normal job of astrocytes.

That is the short story. However, I learned long ago that “if the nomenclature is wrong then the action may be wrong also”. And this is the crux of the matter when applied to the identification and treatment of disorders/diseases of the central nervous system that is the human brain.