Supporting Theories
Vestibulotherapy emerged through a combination of two supporting theories and years of lived experience in pediatric OT. The supporting theories include vestibular rehabilitation and Ayres Sensory Integration. So that you might fully understand the background, I will share the essential elements of these two theories.
Supporting Theory - Pediatric Vestibular Rehabilitation
Vestibular rehabilitation (VR) for children is designed to improve gaze stability, visual-spatial perception, balance, and motor development through exercises embedded throughout the child’s day. Pediatric VR activities employ repetitive and simultaneous head movements with visual focus, static and dynamic balance exercises, and challenging gross motor activities (Christy, 2019; Hall et al., 2016). Pediatric VR is intended for children with any degree of unilateral or bilateral vestibular hypofunction who also have difficulty with gaze stability, balance, and/or motor skill development (Christy, 2019).
VR evidence supporting the proposed mechanism of change is based upon three theories of neural plasticity: adaptation, substitution, and habituation (Hall et al., 2016). Adaptation invokes changes at the neuron level of the vestibular nuclei, impacting the remaining functional portions of the peripheral vestibular system (Christy, 2019). Substitution relies on compensation from other areas of the central nervous system (Christy, 2019). Habituation improves the individual’s tolerance to motion through desensitization through repeated motion over time (Christy, 2019).
Supporting Theory – Ayres Sensory Integration
Sensory integration is the process by which people register, modulate, and discriminate sensations received through the sensory systems to produce purposeful, adaptive behaviors in response to the environment (Ayres, 1972, as cited by Smith-Roley et al., 2007). In ASI there exists an intentional collaboration between child and therapist to create a play scheme, where the child actively engages in affordances of tactile, proprioceptive, and / or vestibular sensations, producing an adaptive response during occupations of play that employ the child’s strengths and challenges (Lane et al., 2019; Roley & Mailloux, 2020). It is through this adaptive response where sensory integration and neural connections develop in response to the child’s ability to receive and process sensation from movement and the environment and use it to plan and organize behavior (Lane et al., 2019; Roley & Mailloux, 2020; Smith-Roley et al., 2007). Without advanced training, ASI is often confused with other sensory based interventions, which provide tactile, vestibular, and /or proprioception to engage the child through means of regulation or modulation of sensory reactions. Unless its application meets the ten elements of fidelity (Parham, 2008, 2011), simply employing these sensory affordances is not Ayres Sensory Integration.
Ayres Sensory Integration (ASI) theory is based on the understanding that impaired sensory and neurological processing impedes development of skills needed for occupational performance. According to Dr. Ayres, children who demonstrate participation challenges often have vestibular-based deficits that could be readily improved through OT, resulting in greater performance in childhood occupations (Ayres 1978, as cited by Roley et al., 2007). Outcomes of Ayres Sensory Integration illustrate how sensory processing integrates with cortical systems to evoke change in our emotional, social, and learning pathways. Sensory Integration speaks to our abilities to receive and process sensory information from our environment, our stored perceptions, and from within our bodies so that we may learn and participate in daily social and academic occupations (Lane et al., 2019).
Through measures of fidelity, Ayres Sensory Integration has distinguished itself from other sensory-based interventions and become an area of evidence-based practice for children with autism (Shoen, et al., 2019; Schaff et al., 2015). While some of the most impressive gains included participation in self cares, increased independence with ADLs, and improved confidence, sense of self-worth, risk taking, and perceived social competence (Schaff et al., 2015), these were not the original aim of Ayres’ Sensory Integration theory (Aryes, 2005, 1976). Rather, Ayres’ focus was to improve academic performance for those children identified as having a learning disability (Aryes, 2005, 1976). “Learning is dependent on the ability to receive and process sensation from movement (vestibular) and the environment and use it to plan and organize behavior” (Roley, et al., 2007, p5). Through a combination of the ASI theory and contemporary neuroscience evidence of vestibular interventions for improving memory and cognitive processes, one could postulate a renewed connection for ASI to support learning outcomes (Lane et al., 2019; Hitier et al., 2014; Koziol et al., 2014; Besnard et al., 2018).
Through improved vestibular processing and sensory integration we develop ideation, body scheme, and internal maps that interact to connect knowledge about our body (sensory and motor maps) with thoughts and ideas to formulate new plans and envision increasingly more complex actions and interactions (Kaye, 2018; Lane et al., 2019). When we effectively take in sensory information and create sensory memories, we store these perceptual memories for later use to expand ideation. Similarly, we build perceptual maps, motor memory, and action schemas (motor planning to refined automated motor plans) to draw upon for increasingly more complex interactions with our environment (Mailloux & Roley, 2020). While building increasingly efficient sensory integration, one develops action chains, which are complex motor sequences that are linked together to provide efficiency with performing skills and navigating through more complex processes (Kaye, 2018). Developing pathways are reinforced by vestibular innervation, which increases memory, sequencing, and ordinance for language and motor skills (Kaye, 2018).
In consideration of this complex tiered learning through ASI, we begin to recognize how ASI, when done with fidelity, is so much more than sensory based interventions that are done to a child to help them regulate or modulate sensory input. ASI interventions including vestibular applications, improve body schema, perceptual awareness, repertoire of action skills, future actions, organizing time and materials, building increasingly complex motor schemes, and anticipating the need for action (Kaye, 2018; Mailloux & Roley, 2020). Outside of ASI, pediatric therapists need to advocate for clinical practice guidelines on developmental vestibular applications to meet the needs of children.
