Understanding Sensory Processing in Autism and the Limitations of Exposure Therapy

Sensory processing refers to how the brain interprets and responds to sensory stimuli from the environment. In autistic individuals, sensory processing can significantly differ from the non-autistic experience, leading to heightened or diminished sensitivity to sounds, lights, textures, smells, and tastes. These differences in sensory processing can profoundly affect daily functioning and quality of life.

Autistic individuals may experience sensory stimuli in various ways:

Hypersensitivity: Over-responsiveness to sensory input, where even mild stimuli can be overwhelming or painful. For example, a loud noise might feel excruciatingly loud, or certain fabrics might feel unbearably scratchy.

Hyposensitivity: Under-responsiveness to sensory input, where individuals may not notice stimuli that others find obvious. For instance, they might not respond to their name being called or seek out intense sensory experiences to feel 'normal' sensations.

Sensory Seeking: Craving certain sensory inputs, such as spinning, jumping, or touching specific textures, to regulate sensory experiences.

Sensory Avoidance: Actively avoiding certain stimuli that are overwhelming or unpleasant, such as covering ears to block out noise or refusing to wear specific types of clothing.

Anxiety and Exposure Therapy

Anxiety is a common mental health condition characterised by excessive worry, fear, and physical symptoms such as increased heart rate, sweating, and tension. Exposure therapy is a widely used technique in treating anxiety disorders. It involves gradually and repeatedly exposing an individual to anxiety-provoking stimuli or situations in a controlled and safe manner. The goal is to reduce the response to fear over time through habituation and cognitive restructuring.

Exposure Therapy and Sensory Processing Issues

While exposure therapy is effective for anxiety, its application to sensory processing issues in autism is problematic. Sensory processing differences, especially hypersensitivity, can cause genuine pain and distress that is not merely a product of irrational fear but a physical and neurological response. Here are the key points to consider:

Physical Pain and Distress: For many autistic individuals, sensory stimuli are not just uncomfortable but can be intensely painful. For example, certain sounds might cause physical pain, or specific textures can lead to a feeling of being physically hurt. Exposure to these stimuli does not reduce pain or make pain more tolerable.

Risk of Trauma: Subjecting someone to painful sensory stimuli with the hope that they will 'get used to it' can be traumatic. Unlike anxiety, where the fear response can diminish through repeated exposure, the pain response to sensory stimuli may not decrease and can lead to increased anxiety and avoidance behaviours.

Individual Differences: Sensory experiences vary greatly among autistic individuals. While some might benefit from gradual exposure to mildly uncomfortable stimuli to increase tolerance (e.g., using a weighted blanket for sensory regulation), others might find the same approach intolerable. Tailored approaches that respect individual sensory profiles are crucial.

Appropriate Approaches to Sensory Processing Issues

For autistic individuals with significant sensory processing issues, alternative strategies are more appropriate than exposure therapy:

Sensory Integration Therapy: This therapy aims to help individuals process and respond to sensory information more effectively. It involves structured activities that are designed to meet the person's specific sensory needs and help them develop coping strategies.

Environmental Modifications: Creating sensory-friendly environments can help reduce exposure to overwhelming stimuli. This might include using noise-cancelling headphones, adjusting lighting, or providing sensory breaks in a quiet space.

Coping Strategies and Tools: Providing tools and strategies to manage sensory overload, such as fidget toys, weighted blankets, or sensory diets (planned and scheduled activities that provide the sensory input a person needs).

Gradual Exposure with Consent: In cases where minor sensory issues can be addressed with exposure, it must be done with the individual's consent and comfort in mind, ensuring they have control over the process.

Decrease background anxiety: Sensory sensitivity and intolerance increase as anxiety increases. Using environmental modifications suitable to the person autistic profile, and increasing their coping strategies for recognising and managing anxiety can reduce the distress involved with sensory processing difference, including the perception of the intensity of the stimulus.

Conclusion

While exposure therapy is effective for treating anxiety, it is not suitable for addressing sensory processing issues in autism, especially when these issues cause significant pain and distress. Understanding the unique sensory profiles of autistic individuals and using appropriate strategies is essential for providing effective support without causing further harm or trauma.

References

Case-Smith, J., Weaver, L. L., & Fristad, M. A. (2015). A systematic review of sensory processing interventions for children with autism spectrum disorders. Autism, 19(2), 133-148.

Dellapiazza, F., Vernhet, C., Blanc, N., Miot, S., Schmidt, R., & Baghdadli, A. (2018). Links between sensory processing, adaptive behaviours, and attention in children with autism spectrum disorder: A systematic review. Psychiatry Research, 270, 78-88.

Krijn, M., Emmelkamp, P. M., Olafsson, R. P., & Biemond, R. (2004). Virtual reality exposure therapy of anxiety disorders: A review. Clinical psychology review, 24(3), 259-281.

Muskett, A., Radtke, S., White, S., & Ollendick, T. (2019). Autism spectrum disorder and specific phobia: The role of sensory sensitivity: Brief review. Review Journal of Autism and Developmental Disorders, 6, 289-293.

Schoen, S.A., Lane, S.J., Mailloux, Z., May-Benson, T., Parham, L.D., Smith Roley, S. and Schaaf, R.C. (2019), A systematic review of ayres sensory integration intervention for children with autism. Autism Research, 12: 6-19. https://doi.org/10.1002/aur.2046