Rooting Reflex


The rooting reflex is one of the involuntary primitive motor reflexes, which are also known as the frontal release reflexes, that are mediated by the brainstem. It initiates when the corner of an infant’s mouth is stimulated. When the mouth is touched or stroked, the newborn will turn his or her head towards the stimulus and open the mouth with tongue thrusting. The rooting reflex is present at birth (approximately 28 week gestation) and lasts about 4 to 6 months until the frontal lobe of the cerebral cortex develops and suppresses the primitive motor reflexes. As the frontal lobe matures, the primitive reflexes are replaced with voluntary motor functions. The age when each primitive reflex disappears varies. For example, the plantar grasp reflex disappears after about 9 to 12 months.[1][2][3]

The rooting reflex is essential for survival and growth as it helps the newborn find the source of food (breast or bottle) and initiate feeding.[3] It is important to differentiate between the rooting reflex and the sucking reflex, which is also involved in nutritional intake. While the rooting reflex occurs when the corner of a baby’s mouth is stimulated, the sucking reflex initiates when the roof of his or her mouth is stimulated. The sucking reflex usually appears around 30 to 35 weeks. The sucking reflex is responsible for the coordination of breathing with swallowing, which starts to develop around 37 weeks.[4] During swallowing, epiglottic closure temporarily interrupts breathing and prevents food from entering the lungs and causing pulmonary aspiration.[5]

Issues of Concern

Although the rooting reflex disappears typically after 4 to 6 months, its persistence after the expected resolution period may suggest congenital cerebral injury. Multiple reflexive abnormalities may be observed with the rooting reflex, as they are commonly regulated by the frontal lobe. Hyperreflexia responses may suggest neonatal withdrawal after in utero exposure to maternal substance abuse, such as heroin or opiate medications. Recurrence of the reflexes in adults suggests central nervous system pathologies. It may be related to neuronal loss related to normal aging or dementia. Persistence or reappearance of primitive reflexes may serve as an early sign of neurological dysfunction. Further testing should be performed to detect any underlying conditions. Early detection of disease will allow providers to plan out interventions promptly and prevent or slow down the progression of the disease.[6][7][8]

Clinical Significance


The persistence of the rooting reflex commonly with other primitive reflexes after 4 to 6 months may suggest congenital cerebral palsy. If the rooting reflex persists, the infant may have drooling and a tongue that sits too forward in the mouth. The child will have difficulty swallowing and chewing because of the dysfunctional tongue. Other clinical manifestations include hypotonic or hypertonic muscle tone, asymmetric posture and gait, and delayed developmental milestones. The persistence of primitive reflexes in infancy may also be an early sign of cognitive-developmental delay or autism. Patients with cerebral palsy often develop other conditions, such as learning disability, seizures, and visual or hearing impairment.[9][10][11]

The trigeminal cranial nerve (CN 5), which is responsible for facial sensation, is involved in the rooting reflex. In an infant with an intact CN 5, stroking or touching the corner of his or her mouth will initiate the rooting reflex. If the infant has CN 5 dysfunction, it may result in the absence of the rooting reflex. Congenital trigeminal anesthesia is a rare condition but can significantly impact multiple aspects of neonatal health.[12][13] Corneal epithelial injuries are common clinical manifestations because the afferent limb of the corneal reflex is innervated by the first branch of the CN 5. In contrast, the efferent limb of the reflex is innervated by the facial nerve (CN 7).[14] With the inability to blink appropriately, infants are at higher risk of recurrent corneal epithelial injuries. Loss of facial sensation and decreased lacrimation are also possible clinical manifestations.[15] In a 2002 study to evaluate the development of the corneal reflex in healthy full-term babies, 190 babies were examined in the nursery, and 200 babies were examined in the outpatient clinic. The babies in the nursery ranged between 1 to 3 days of age, and the babies examined in the clinics were ages 1 week to 12 weeks. The study reported that half of the infants developed tactile corneal reflex at 3.5 weeks, and all of the infants developed the corneal reflex at 12 weeks.[16]


Rooting reflexes can be observed in adult patients with frontal lobe pathology. They often present with other primitive reflexes that are normally suppressed by the frontal lobe of the cerebral cortex. Patients with a frontal lobe lesion are also incapable of making decisions, have different personalities, and are not able to control emotions or maintain social interactions. Causes of frontal lobe diseases include head trauma, frontal lobe tumor, multiple sclerosis, and dementia. Frontotemporal dementia most commonly occurs in patients between the ages of 45 and 65.[17] It affects both frontal and temporal lobes of the brain and results in multiple dysfunctions such as apathy, disinhibition, language disability, deficits in executive control.

Nursing, Allied Health, and Interprofessional Team Interventions

The rooting reflex is crucial to initiate feeding and promote neonatal growth. Clinicians and nurses should perform thorough neonatal neurological examinations to ensure that all primitive reflexes, including the rooting reflex, are intact. The persistence of the reflex after 4 to 6 months may suggest several conditions, including congenital cerebral palsy and autism. The medical community should educate parents to pay close attention to the child and evaluate whether the reflexes disappear after 4 to 6 months. Parents should be reminded to set up a follow-up appointment after the resolution period. Regular visits may help with the early detection of the disease and the prevention of possible complications. If an infant has congenital trigeminal anesthesia, their clinician should refer the patient to an ophthalmologist to prevent serious corneal disease.

When adult patients present with the recurrence of primitive reflexes, clinicians should order appropriate tests to make a correct diagnosis. Because patients with frontal lobe lesions show impulsive and risky behaviors, family members may show frustration and inability to cope with the patient's disease. Clinicians and nurses should fully explain the situation to the family members about the effects of brain damage and any treatments that may reverse or slow down the progression of the disease. Social services and programs should be employed in these cases to help the patient and the family cope with the progression of the disease and to provide support in the home as much as possible.



Hannah Yoo


Dana M. Mihaila


4/24/2023 12:34:02 PM



Modrell AK, Tadi P. Primitive Reflexes. StatPearls. 2023 Jan:():     [PubMed PMID: 32119493]


Schott JM, Rossor MN. The grasp and other primitive reflexes. Journal of neurology, neurosurgery, and psychiatry. 2003 May:74(5):558-60     [PubMed PMID: 12700289]


Glodowski KR, Thompson RH, Martel L. The rooting reflex as an infant feeding cue. Journal of applied behavior analysis. 2019 Feb:52(1):17-27. doi: 10.1002/jaba.512. Epub 2018 Sep 24     [PubMed PMID: 30251406]


Sohn M, Ahn Y, Lee S. Assessment of Primitive Reflexes in High-risk Newborns. Journal of clinical medicine research. 2011 Dec:3(6):285-90. doi: 10.4021/jocmr706w. Epub 2011 Nov 10     [PubMed PMID: 22393339]


Matsuo K, Palmer JB. Coordination of Mastication, Swallowing and Breathing. The Japanese dental science review. 2009 May 1:45(1):31-40     [PubMed PMID: 20161022]


Mestre T, Lang AE. The grasp reflex: a symptom in need of treatment. Movement disorders : official journal of the Movement Disorder Society. 2010 Nov 15:25(15):2479-85. doi: 10.1002/mds.23059. Epub     [PubMed PMID: 20848621]


Damasceno A, Delicio AM, Mazo DF, Zullo JF, Scherer P, Ng RT, Damasceno BP. Primitive reflexes and cognitive function. Arquivos de neuro-psiquiatria. 2005 Sep:63(3A):577-82     [PubMed PMID: 16172703]


Futagi Y, Toribe Y, Suzuki Y. The grasp reflex and moro reflex in infants: hierarchy of primitive reflex responses. International journal of pediatrics. 2012:2012():191562. doi: 10.1155/2012/191562. Epub 2012 Jun 11     [PubMed PMID: 22778756]


Agarwal A, Verma I. Cerebral palsy in children: An overview. Journal of clinical orthopaedics and trauma. 2012 Dec:3(2):77-81. doi: 10.1016/j.jcot.2012.09.001. Epub 2012 Sep 18     [PubMed PMID: 26403442]

Level 3 (low-level) evidence


Panteliadis CP, Hagel C, Karch D, Heinemann K. Cerebral Palsy: A Lifelong Challenge Asks for Early Intervention. The open neurology journal. 2015:9():45-52. doi: 10.2174/1874205X01509010045. Epub 2015 Jun 26     [PubMed PMID: 26191093]


Chinello A, Di Gangi V, Valenza E. Persistent primary reflexes affect motor acts: Potential implications for autism spectrum disorder. Research in developmental disabilities. 2018 Dec:83():287-295. doi: 10.1016/j.ridd.2016.07.010. Epub 2016 Aug 29     [PubMed PMID: 27595468]


Iyer A, Hassan E, Newman W, Kneen R. Congenital trigeminal anaesthesia: a rare preventable cause of visual loss in children. BMJ case reports. 2012 Jul 3:2012():. doi: 10.1136/bcr.03.2012.5955. Epub 2012 Jul 3     [PubMed PMID: 22761208]

Level 3 (low-level) evidence


Rosenberg ML. Congenital trigeminal anaesthesia. A review and classification. Brain : a journal of neurology. 1984 Dec:107 ( Pt 4)():1073-82     [PubMed PMID: 6509308]


Sanders RD. The Trigeminal (V) and Facial (VII) Cranial Nerves: Head and Face Sensation and Movement. Psychiatry (Edgmont (Pa. : Township)). 2010 Jan:7(1):13-6     [PubMed PMID: 20386632]


Morishige N, Morita Y, Yamada N, Nishida T, Sonoda KH. Congenital hypoplastic trigeminal nerve revealed by manifestation of corneal disorders likely caused by neural factor deficiency. Case reports in ophthalmology. 2014 May:5(2):181-5. doi: 10.1159/000364899. Epub 2014 Jun 19     [PubMed PMID: 25076898]

Level 3 (low-level) evidence


Snir M, Axer-Siegel R, Bourla D, Kremer I, Benjamini Y, Weinberger D. Tactile corneal reflex development in full-term babies. Ophthalmology. 2002 Mar:109(3):526-9     [PubMed PMID: 11874756]


Johnen A, Bertoux M. Psychological and Cognitive Markers of Behavioral Variant Frontotemporal Dementia-A Clinical Neuropsychologist's View on Diagnostic Criteria and Beyond. Frontiers in neurology. 2019:10():594. doi: 10.3389/fneur.2019.00594. Epub 2019 Jun 7     [PubMed PMID: 31231305]