Retained Primitive Reflexes
What are primitive reflexes?!?!? Primitive reflexes are involuntary motor responses originating in the brain stem. They are automatic stereotypic movements, they do not require cortical (thought) involvement, and are fully present in full term births! Primitive reflexes are needed for development in the womb and in the early months of life. As the cerebrum (higher brain center) matures, these primitive reflexes are no longer needed, and replaced by voluntary movement control. This process is a part of optimal neurological organization and development. If Primitive Reflexes are retained beyond the first few months to first year of life, they can interfere with sensory-motor, social, and academic development. These reflexes are associated with one or more of the Sensory Processing Systems: Auditory, Taste, Tactile, Smell, Visual, Vestibular, Proprioceptive and/or Interoceptive. Therefore, if retained, an individual may experience dysfunction within one or several of the sensory processing systems.
Asymmetrical Tonic Neck Reflex (ATNR)⠀⠀⠀⠀
When an infant turns their head to one side, the arm and leg of that same side automatically extends while the opposite side bends. Also known as "the fencing reflex". ATNR acts to stimulate muscle tone and the vestibular system in utero. It assists the baby in the birthing process and provides foundational skills for eye hand coordination. ATNR typically integrates between 4-6 months of age. ⠀⠀⠀⠀⠀⠀⠀⠀⠀
When ATNR is retained, children may appear easily distracted, have messy handwriting, demonstrate poor coordination, experience reading/writing difficulties, and have poor visual tracking. Children may lose their place easily while completing schoolwork and have trouble with auditory listening.
Symmetrical Tonic Neck Reflex (STNR)
STNR can be clearly observed at 6-9 months. This reflex helps provide separation between the upper and lower halves of the body. A normal appearance of the reflex in infants is to assume quadruped (hands and knees position). When the infant extends the head and neck, their elbows extend (straighten), and the knees flex (bend). The reverse occurs when bending the head and neck leading the elbows to flex and the knees to extend. This reflex integrates (disappears) by 9-11 months of age, after the infant has learned independent limb movement for crawling.
Observable motor, social, and learning problems associated with a retained STNR include: no crawling or unusual crawling in infants, poor posture, tendency to slump when sitting, sitting in a "W" position, Simian (ape-like) walk, poor balance, poor eye-hand coordination, messy eating, difficulties with near/far visual gaze shifting (child cannot change focus easily from board to desk), slowness with copying tasks, reading and writing challenges, poor swimming skills, and difficulty with social cues.
The Moro Reflex is the earliest reflex to form in utero during the 2nd trimester. It is the foundation for the fight or flight response that alerts the body of danger when experiencing sudden changes in sensory stimuli (sound, touch, movement). It is also the reflex that helps the infant take their first breath outside of the womb. In infancy, it is characterized by an abrupt extension and outward movement of the arms followed by flexing and drawing the arms inward and often subsequent crying. The sympathetic nervous system is activated, characterized by increased heart rate, blood pressure, and respiratory rate as adrenaline and cortisol are released. The Moro reflex becomes integrated 4-6 months after birth. Some signs of a retained Moro reflex include…
· Sensitivity to sound
· Sensitivity to light
· Insecurity with feet leaving the ground
· Fearful in new situations/phobias
· Hypersensitive to touch
· Decreased balance/coordination
· Visual perceptual problems
· Mood swings
The Spinal Galant reflex helps the infant move through the birthing process. After birth, this reflex helps establish greater range of motion in the hips. The reflex is observed when gentle pressure is applied on either side of the spine. If the child responds by curving their trunk toward the stimulated side, this indicates a positive reflex. Typically, the reflex is integrated between 3 and 9 months of age. Children who do not properly integrated this reflex may have trouble with postural control, demonstrate increased fidgeting, have difficulty using hands at midline, exhibit delayed crawling, have decreased bladder control and poor attention/concentration.
Tonic Labyrinthine Reflex (TLR)
The TLR is present in utero and assists the baby with their posture in relation to their head position. It aides the infant in developing movement away from the fetal position. The forward TLR (flexion) typically integrates by 6 months of age and the backward TLR (extension) integrates between 6 months-3 years. TLR is strongly associated with balance due to its links to the vestibular system.
If the reflex is retained, children may experience toe walking, poor muscle tone, motion sickness and decreased spatial awareness. A retained TLR may also decrease ability to navigate through space and present with insecurity when feet leave the ground.
The rooting reflex develops in utero and integrates around the age of 4 months old. It helps the infant orient their mouth for breastfeeding. When stroking a baby’s cheek, they will turn towards you, usually looking for food.
Retainment of the Rooting reflex may impact several areas including,
tactile sensitivity around the face
poor manual dexterity
Occupational Therapists can evaluate for potential retainment of primitive reflexes. If persistent reflexes are identified, treatment is provided through play skills and targeted exercises. Development and implementation of a home program is imperative for optimal results. Your therapist can support your child’s involvement in a treatment plan that can be carried out and tracked at home.