Continuity and discontinuity ol behavioral inhibition and exuberance: Psychophysiological and behavioral influences across the first four years of life

Four-month-old infants were screened (N = 433) for temperamental patterns t hought to predict behavioral inhibition, including motor reactivity and the expression of negative affect. Those selected (N =153) were assessed at mu ltiple age points across the first 4 years of life for behavioral signs of inhibition as well as psychophysiological markers of frontal electroencepha logram (EEG) asymmetry. Four-month temperament was modestly predictive of b ehavioral inhibition over the first 2 years of life and of behavioral retic ence at age 4. Those infants who remained continuously inhibited displayed right frontal EEG asymmetry as early as 9 months of age while those who cha nged from inhibited to noninhibited did not. Change in behavioral inhibitio n was related to experience of nonparental care. A second group of infants, selected at 4 months of age for patterns of behavior thought to predict te mperamental exuberance, displayed a high degree of continuity over time in these behaviors.