depression, but that biochemical treatment would help overcome depression. Pfeiffer conducted a 12-year study which allowed him to classify behavior disorders into four categories based on trace metal patterns. Type A: high copper/zinc ratio, depressed hair sodium, potassium and lead sensitivity. These individuals exhibit episodes of fighting, oppositional behavior and mood swings. Type B: depressed hair copper, pyroluria, elevated histamine and elevated toxic metals. They exhibit assaultive behavior, absence of remorse, pathological lying, fascination with fire and cruelty towards animals. Type C: "mal absorbers", tend to be slender, usually impulsive and oppositional. Type D: depressed manganese and chromium levels. They exhibit nonviolent delinquent behavior. Carl Pfeiffer died at the age of 80 at the Princeton Brain Bio Center. He suffered a heart attack . Bibliography Pfeiffer, Carl C. Ph.D., M.D. and Scott LaMola, B.S. Zinc and Manganese in the Schizophrenias First published in Journal of Orthomolecular Psychiatry, Vol. 12, No. 3, 1983 External links The Earth House ''- Dr. Pfeiffer's "Princeton Brain Biocenter" renamed the "Carl C. Pfeiffer Institute" after his passing, has been retired. References 1908 births 1988 deaths Pfeiffer Alternative medicine researchers Bipolar disorder researchers American pharmacologists Project MKUltra