Humoral Phototransduction: Blood Is a Messenger

Drawing upon the premise that there is a parsimony to nature, the author proposes that heme moieties and bile pigments in animals mediate some non-visual influences of light upon neuroactive gases and biological rhythms. Primary abnormalities in synthesis and regulation of blood and bile may, therefore, cause some neuropsychiatric illnesses. Light may play a critical role in neurotransmission. NEUROSCIENTIST 2:207-210, 1996