Fundamental Systems of Emotion in the Mammalian Brain
Jeffrey A. Gray Institute of Psychiatry, England
It is not my intention in this chapter to address directly developmental issues; I have neither clinical experience nor research data to render plausible such an intervention in a field not my own. Rather, I wish to present an outline sketch of what is known about those neuropsychological systems that, in the adult mammal (plausibly including humans), control emotional behavior. For I suppose that the work of developmental psychologists is likely to be aided by an understanding of the final product towards which the subjects they study are tending, and I also suppose that many of the abnormalities of behavior and development that concern the pediatric psychiatrist are emotional in nature.
The sketch I present is underpinned by a number of basic assumptions.
The first is that emotions consist in specific states of the CNS, an abbreviation which stands simultaneously for the conceptual nervous system ( Hebb, 1955), that is, the system deduced from purely behavioral analysis of the relations between stimulus input and response output, and the real central nervous system located inside the skull.
The second assumption is that emotions differ from other such central states in that they are elicited by reinforcing stimuli or events. In this context, the term reinforcing stimuli (and its congeners, reinforcement, reinforcer, etc.) has the standard definition common in learning theory (e.g., Gray, 1975), that is: Stimuli that, when made contingent upon a behavioral response, alter the subsequent probability of emission of that response, whether by increasing this