Philip R. Zelazo
Tufts University School of Medicine
Professionals responsible for advising parents about childcare have long known that the persistence of certain reflexive behaviors in infants is often evidence of neurological damage. Normally many of the infant's integrative reflexes diminish or disappear within the first 10 or 12 months of life. The walking reflex diminishes to near zero by 8 weeks ( Zelazo, Zelazo, & Kolb, 1972) and the Moro reflex terminates by about 6 months ( McGraw, 1943). The occurrence of a full-fledged Moro reflex in an 10- month-old child, arms extended and brought toward the midline with grasping of the hands, to the sudden removal of support, may therefore raise concern about the infant's neurological status. This concern rests on a firm foundation of clinical experience; in some cases of neurological insult, the so-called integrative reflexes, such as the Moro reflex, persist or reappear.
Generalizations are occasionally made to less obvious cases, however, implying that the persistence or reoccurrence of certain reflexes beyond prescribed ages is synonymous with abnormal development. One obvious implication, voiced even today, is that we should not tamper with any of the infant's reflexes. Some suggest that the presence of reflexively based responses beyond certain ages, such as walking or standing in the 2-month- old infant, is cause for concern (e.g., Gotts, 1972). This is a reasonable view if one regards the infant as a defenseless organism. There is a sense