As hormonal amplification is the hallmark of all of the brain-to-gland relationships of neuroendocrinology, hormonal deamplification is the hallmark … - Richard Bergland

The ventricles of the human brain... are filled with hormones, and until the hormones swimming in these oceans are dredged out, countless millions of our fellows will remain with brain illnesses that can be neither understood nor treated. Many of their hormone-hungry brains may be fixed as easily as hormone-hungry bodies are fixed with thyroid hormone, insulin, oestrogen and testosterone, but that work cannot begin until cause and effect relationships between brain hormones and brain diseases have been established.

Regulatory messages or hormones flow from specific regions of the brain to specific glands within 'hollow' nerve fibres exactly as Erasistratus, Galen and Descartes had taught.

Some kinds of hormones, the 'steroids', pass readily into the brain, but the 'peptide' hormones produced by the pituitary, the gut, and any other glands do not easily pass through the walls of brain capillaries.