Reflexes which are normally found in infancy but which disappear with brain maturation during childhood may be labeled as "primitive reflexes" if they reemerge in adulthood as a consequence of pathological states. Many of these reflexes are seen with frontal lobe pathology (e.g., grasp, pout/snout, palmomental, rooting, corneomandibular) and hence may also be known as "Frontal Release Signs." However, the term "primitive reflex" could equally apply to Babinski’s sign which is not necessarily frontal in origin.
Schott JM, Rossor MN. The grasp and other primitive reflexes. Journal of Neurology, Neurosurgery and Psychiatry 2003; 74: 558-560