Human beings do not merely possess a single brain within the cranium, but within the heart and spinal column as well, since in esoteric psychology, a brain is a psycho-physiological machine that processes energies of different modifications. Just as the mind has its nervous systems and basis within the material, cranial matter, likewise the heart (the seat of emotions) and the spinal column / sexual organs (the seat of instinct, movement, and sexuality) possess their own forms of intelligence we must become familiar with. By comprehending our human organism: mind (thought), heart (emotions), and sexuality (desire and attraction), we can learn to use the machinery of these three brains for our individual self-transformation and growth.

Resources and References:

https://chicagognosis.org/lectures/the-three-brains