Differences in the Autonomic and Somatic Conditioning of Infants

Temporal and auditory classical conditioning of an autonomic response (pupillary reflex) and a somatic response (eyeblink) were attempted in 4 separate experi-ments with clinically normal human infants. Time as a conditional stimulus (CS) was effective for conditioning pupillary dilation and constriction, but sound as CS was ineffective. Conversely, sound was effective for conditioning eyeblinking, but time was not. These discrepancies in conditionability were related to (1) the parameters comprising the classical conditioning paradigms employed, and (2) the implications of infant learning for developmental neurophysiology. I N CONSIDERING the etiology of psycho-somatic diseases, both clinicians and re-searchers agree that the vulnerability of an organ system to illness is in part the outcome of learning or conditioning— particularly early learning, because it is during infancy that the organism is most responsive to the forces of environmental modification and because patterns estab-lished early have a high probability of being perpetuated. The organ systems of particular im