He completed an endocrinology fellowship in 1982 at the Veterans Administration Medical Center in New Orleans, Louisiana, with Abba Kastin, studying the blood-brain barrier (BBB).

In 2010, he moved to his present location at the VA Puget Sound Health Care System and University of Washington in Seattle, WA.

[2][5] Banks' interest for more than 40 years has focused on brain-body communication as mediated by the handling of peptides, regulatory proteins, and other informational molecules by the BBB.

[6] He has applied this approach to studies of obesity/body weight regulation, Alzheimer's disease/neurodegenerative diseases, neuroimmunology/neuroinflammation, CNS manifestations of diabetes mellitus, drug delivery to the central nervous system, and AIDS.

He has also published on animal assisted therapy in nursing homes, robotics in geriatric medicine, sleep physiology, traumatic brain injury, and was first author on the paper first describing primary adrenal hyperplasia.