Frontal Release Signs

Frontal Release Signs are so named because of the belief that they are released from frontal inhibition by diffuse pathology within the frontal lobes (usually vascular or degenerative) with which they are often associated, although they may be a feature of normal ageing. Some of these responses are present during infancy but disappear during childhood, hence the terms "primitive reflexes" or "developmental signs" are also used (Babinski’s sign may therefore fall into this category). The term "psychomotor signs" has also been used since there is often accompanying change in mental status.
The Frontal Release Signs may be categorized as:

  1. Prehensile:

Sucking reflex (tactile, visual) Grasp reflex: hand, foot
Rooting reflex (turning of the head toward a tactile stimulus on the face)

  1. Nociceptive:

Snout reflex Pout reflex
Glabellar (blink) reflex Palmomental reflex
The corneomandibular and nuchocephalic reflexes may also be categorized as "frontal release" signs. Some are of little clinical value

dementia, gait disorder (frontal gait, marche à petit pas), urinary incontinence, akinetic mutism and gegenhalten.
Common causes of these findings are diffuse cerebrovascular disease and motor neurone disease.



Franssen EH. Neurologic signs in ageing and dementia. In: Burns A (ed.). Ageing and dementia: A methodological approach. London: Edward Arnold, 1993: 144-174


Cross References

Age-related signs; Babinski’s sign (1); Corneomandibular reflex; Gegenhalten; Grasp reflex; Marche à petit pas; Palmomental reflex; Pout reflex; Rooting reflex; Sucking reflex