Primitive reflexes – sometimes we need to test them
At times it may be necessary to carry out some reflex tests during a review, if I suspect that a child has retained one or more primitive reflexes connected to their hands and mouth. Normally these reflexes will have inhibited during baby’s first year, but occasionally they are retained and can impact speech and language. It may be possible to help the child integrate the reflexes with some exercises to minimise any difficulties.
Rooting and Sucking
Both these reflexes influence the movement of the tongue and lips. The Rooting reflex emerges at birth as the lips purse in search of food and, once in contact, draw the object into the mouth. If the object is a nipple or teat of a bottle, the reflex has served its purpose and the baby satisfies their hunger by feeding, thus activating the Sucking reflex. The tongue muscles push the nipple or teat to the roof of the mouth and rhythmic sucking releases the milk.
If rooting does not result in the discovery of food because the baby has been separated from the mother or they are being fed by intravenous drip, after a couple of days the Rooting reflex will wane. This means that the sensitive muscles around the mouth used in the pursing movement will not be exercised fully and this may impact the future control of these muscles when the child starts to experiment with speech.
Other difficulties may occur if the Sucking reflex does not inhibit within its rightful period of 3-4 months postnatal. Its continued presence can affect the development of a more mature swallow pattern as the tongue is positioned further forward in the mouth and the ability to chew is hampered. An immature swallow pattern can result in the formation of an arched palate. Also, the retention of this reflex may affect full closure of the mouth, breathing patterns and in turn influence the way that words come to be articulated.
The Babkin response is present from birth for approximately four months, with a palmar-mandibular link of pressure on the palm eliciting a rotation of the head to the midline, flexion of the head and the mouth opening in anticipation of feeding. If this response continues, the child may find that any task using the hands provokes mouth movements and vice versa, creating the possibility of tension in facial muscle usage and it would be an indicator that the motor development aspect of speech and language has not progressed correctly.
A baby’s hand movements develop from a kneading action to a whole hand grasp as objects are interrogated by placing in the mouth and the sensory world around the baby is interpreted through hand and mouth investigation and thence onto a pincer grip of thumb and forefinger. If the Palmar reflex is retained, the thumb and four fingers move as one, with difficulty shown in pincer grip holds and independent movement of fingers for fine motor skills. In the babbling phase during the second half of the first year, the baby’s toes can be seen extending and flexing prior to vocalisation. Refinement of both hand and feet movements require the function of the cerebral cortex and corticospinal tract and a major phase in the myelination of the corticospinal tract and the part of the cerebellum responsible for both articulation of the hands, feet and mouth around this time will facilitate this. Sensitive responses to palmar and/or plantar reflex tests and speech difficulties in the older child may point to neurological development delays relating to this myelination stage.