Three primitive reflexes in normal adults.

One or more of three primitive reflexes (palmomental, snout, and corneomandible) was elicited in 50.5% of 105 normal subjects in the third through the ninth decades of life. The reflexes appeared in a patterned fashion with advancing age. The palmomental reflex appeared earliest and was the most frequent reflex elicited at all ages. The snout and corneomandibular reflexes appeared at later ages and were elicited less frequently. The palmomental and snout reflexes often occurred alone, but the corneomandibular was elicited only when one or both of the other reflexes was also present. These reflexes appear to be normal phenomena in a significant proportion of the healthy population.