RESUMO
The insights of ethology-the science of animal behavior from a biological and psychological point of view-were incorporated in the 1950s by the British developmental psychiatrist, John Bowlby, into his attachment theory, which argued that a secure affective base in infancy was critical to the normal development of perception, cognition, learning, and emotion, in addition to that of physical parameters. The theory was illustrated by Harlow's pioneering experiments with baby monkeys: those raised with a wire-frame "mother" failed to thrive, compared with the more normal development of those deriving comfort contact from a terry-cloth surrogate. Modern neuroscience techniques have confirmed that the absence of sensory stimulation during periods of maximal synaptic expansion provides the substrate for a subsequent mood disorder. Ethology offers a novel "nature plus nurture" approach to the development of abnormal mood, as well as a target for treatment.