Sensory Processing Disorder

Are you a parent who has noticed the following in your child: 

• Fear of heights 
• Difficulty or resistance to walking on stairs or escalators 
• Resistance to being upside-down 
• Avoidance of high playground equipment/Climbing 
• Signs of distress when going from a standing up position to a lying down position (ex: during diaper change) 
• Car or motion sickness 
• General slow, cautious movements rather than age-appropriate risk-taking
•  Difficulty jumping with both feet off the ground/jumping from an elevated surface
• Resistance crawling/walking on uneven surfaces (i.e. stepping up & down a curb, walking on a balance beam) 
• Cries or resists having their head tilted back during a bath 
• Dislike swings or other moving toys (i.e. rocking horse, toy car, etc.)
•  Don’t like being picked up 

If the answer to most of the questions above is YES, It could be that the child might be having Gravitational Insecurity. 

Let’s learn about Gravitational insecurity but before that, we need to understand what the Vestibular system (which is also our movement sense) 

What is the vestibular system? 

The Vestibular System’s function is to detect the position and movement of our head in space. This allows for the coordination of eye movements, posture, and equilibrium. The vestibular apparatus is located in our inner ear. 

Vestibular seekers may seek vestibular input through movement & constant physical activity. On the contrary, Vestibular avoiders are highly sensitive to movement and tend to become overwhelmed during everyday activities requiring movements during play. 

Gravitational insecurity 

Children with sensory processing challenges often demonstrate a specific vestibular dysfunction characterized by an irrational fear of movement experiences (changes in head position, not having both feet on the floor, or movements requiring balance) referred to

Little is currently known about the cause or neurological mechanisms of gravitational insecurity although it is believed to be a central nervous system problem. Ayres (2005) originally emphasized the irrational nature of the fear response associated with gravitational insecurity. She described this problem as the child feeling a “primal threat in the pull of gravity” and hypothesized that the limbic system played a role in the child’s perceptions of these fears (Ayres, 1979, pg. 84). Fisher and Bundy (1989) later proposed that gravitational insecurity was a limbic system response specifically to difficulty modulating otolithic vestibular sensory inputs. More recent research has suggested that deficits in the neural integrator function related to velocity storage of vestibular inputs may play a role in this dysfunction (Potegal, 2015; Potegal et al., 2020). The neurophysiological underpinnings of this disorder will require additional research. 

There is, however, some literature on the symptoms characteristic of this disorder. First identified by Dr. A. Jean Ayres (1979), gravitational insecurity is unique among movement-related dysfunctions. Although there may be self-reported dizziness, vertigo, or balance challenges, gravitational insecurity is primarily identified by the individual’s fearful and anxious reactions to specific categories of movements, namely those which involve the feet leaving the ground, changes in head position out of upright, movement on unstable surfaces, and/or the presence of disorienting visual stimuli in conjunction with movement (May-Benson and Koomar, 2007). Behaviourally, gravitational insecurity is characterized by intense anxiety, discomfort and/or fear responses to common activities such as lying supine, assuming inverted head positions (e.g. leaning over), leaning or tipping the head backwards, performing somersaults, stepping over objects, walking on bumpy ground, climbing stairs or up on chairs, jumping, falling, or riding in cars. In children these problems interfere with participation in daily life activities such as descending stairs, exploring playgrounds, engaging in sports, roughhouse play and navigating out of doors on bicycles, skates, etc. (Ayres, 2005). In adults these problems may interfere with daily life activities such as driving, flying in airplanes, climbing on chairs or ladders, or riding on elevators or escalators (May-Benson, 2015). 

Gravitational insecurity has traditionally been identified by occupational therapists through clinical assessment or parent/self-report of symptoms believed to be associated with this problem. 

Intervention strategies and tips for parents 

The Occupational Therapist uses the Sensory Integration approach. Sensory experiences are gradually and slowly introduced to your child so they don’t identify with these experiences in a negative way. The child is guided through a multisensory approach by the therapist to help him explore his environment through vestibular system stimulation. The child is challenged just a little bit initially, which will allow them to gradually start participating in activities that were once terrifying to them. 

As a parent the most important thing to remember is not to force any movements that induce a strong emotional response. These movements are anxiety-inducing and bad experiences can lead to further aversion. It may be hard for you to understand why, but these kids feel like they have lost awareness of where their body is in space.