National Sensory Network

Sensory Modulation and Autism

Research has shown that a significant majority of autistic individuals experience sensory stimuli in unique ways. They may be hypersensitive to certain sounds, lights, or textures, finding these inputs overwhelming and distressing. Conversely, some may be hyposensitive, seeking additional sensory input to feel balanced. These sensory differences can involve any of the senses—sight, sound, smell, taste, touch, balance, and body awareness—and an individual can experience both hypersensitivity and hyposensitivity across different senses or a response may fluctuate depending on a number of factors (time of day, levels of sleep, feeling unwell levels of anxiety, support available in the environment). 

Modulation differences can manifest in various ways. A person who is hypersensitive to touch might find the texture of certain fabrics intolerable, leading to discomfort or even pain. On the other hand, someone who is hyposensitive to touch might seek out deep pressure, like tight hugs, to feel grounded. Similarly, visual hypersensitivity could cause someone to be overwhelmed by bright lights, while hyposensitivity might lead to a preference for bright, bold colors or spinning objects.

Modulation and Overwhelming Environments

These unique sensory experiences can affect various aspects of an autistic individual’s life. In environments that are typically overwhelming—such as busy offices, crowded public spaces, or loud social gatherings—autistic individuals might experience heightened stress and anxiety. Conversely, quieter, more controlled settings can help them feel more comfortable and engaged. Understanding these sensory needs is crucial for creating supportive environments that enhance well-being. 

The Sensory Street research project looked at how public places can be challenging sensory environments for autistic people and what can be changed to make them more accessible and inclusive. Their website provides lots of evidence-based advice on making public spaces more sensory-friendly for autistic individuals.

Sensory Discrimination and Autism

Sensory discrimination refers to the process whereby specific qualities of sensory stimuli are perceived and meaning attributed to them. For example, touching something and realising that it is hard or soft.  This variability can manifest in various ways, such as difficulty differentiating between similar sounds, difficulty with determining how much force they’re exerting on objects, and finding it tricky distinguishing between items with subtle differences, such as coins. These sensory processing differences can impact daily activities, social interactions, and learning experiences.

Praxis and Autism

Praxis is the important ability to conceptualise, plan and execute unfamiliar motor tasks. Sensory systems, including the proprioceptive system, play a crucial role in effective movement planning and execution. This process relies on the integration of multiple sources of sensory information for the individual to effectively plan and sequence their movements to perform the new task. Differences in the way some individuals process this sensory information will impact their praxis abilities.

Although motor skills are not part of the diagnostic criteria for autism, they are now widely recognised as a characteristic of the condition. For example, analysis of a large sample of autistic children found over 80 per cent of the children had a risk for motor impairment or Developmental Coordination Disorder (DCD) present and that this persisted into adolescence.

Stimming and Sensory Self-Regulation

Stimming, or self-stimulatory behaviour, is a vital self-regulation tool for many autistic people. Sensory stimulation plays a crucial role in the development, information processing, and behaviour of individuals, making it essential to understand its impact. Actions such as rocking, hand-flapping, or fidgeting can help them manage overwhelming sensory input and reduce anxiety. These behaviours often provide comfort and aid in maintaining focus and emotional balance. Recognising the importance of stimming and allowing space for it can significantly improve an autistic individual’s ability to cope with their environment.

Additionally, intense interests, often seen in autistic individuals, can have positive aspects. These deep engagements can lead to the development of expertise in specific areas, boosting self-esteem and providing a sense of achievement. These interests can also offer a regulating effect, serving as a sanctuary from the sensory overload of daily life. Encouraging and nurturing these passions can help autistic individuals leverage their strengths and contribute meaningfully to their personal and professional lives.

References

Ashburner, J., Bennett, L., Rodger, S., & Ziviani, J. (2013). Understanding the sensory experiences of young people with autism spectrum disorder: A preliminary investigation. Australian Occupational Therapy Journal, 60(3), 171–180. https://doi.org/10.1111/1440-1630.12025

Bhat, A. N. (2020). Is Motor Impairment in Autism Spectrum Disorder Distinct From Developmental Coordination Disorder? A Report From the SPARK Study. Physical Therapy, 100(4), 633–644.https://doi.org/10.1093/ptj/pzz190

Bhat, A. N., Landa, R. J., & Galloway, J. C. (Cole). (2011). Current Perspectives on Motor Functioning in Infants, Children, and Adults With Autism Spectrum Disorders. Physical Therapy, 91(7), 1116–1129.https://doi.org/10.2522/ptj.20100294

Bar-Shalita, T., Vatine, J.-J., & Parush, S. (2008). Sensory modulation disorder: a risk factor for participation in daily life activities. Developmental Medicine & Child Neurology, 50(12), 932–937. https://doi.org/10.1111/j.1469-8749.2008.03095.x

Ferguson, R., Cross, S., McCanney, J., Kelly, G., Casey, J., & McCaffrey, F. (2014). Sensory processing patterns, activity choice and participation of children with autism across Ireland. Middletown Centre For Autism. www.middletownautism.com.

Hochhauser, M., & Engel-Yeger, B. (2010). Sensory processing abilities and their relation to participation in leisure activities among children with high-functioning autism spectrum disorder (HFASD). Research in Autism Spectrum Disorders, 4(4), 746–754. https://doi.org/10.1016/j.rasd.2010.01.015

Kirby, A. V., Bilder, D. A., Wiggins, L. D., Hughes, M. M., Davis, J., Hall‐Lande, J. A., Lee, L., McMahon, W. M., & Bakian, A. V. (2022). Sensory features in autism: Findings from a large population‐based surveillance system. Autism Research, 15(4), 751–760. https://doi.org/10.1002/aur.2670

Lane, A. E., Young, R. L., Baker, A. E. Z., & Angley, M. T. (2009). Sensory Processing Subtypes in Autism: Association with Adaptive Behavior. Journal of Autism and Developmental Disorders, 40(1), 112–122. https://doi.org/10.1007/s10803-009-0840-2

Miller, L. J., Anzalone, M. E., Lane, S. J., Cermak, S. A., & Osten, E. T. (2007). Concept evolution in sensory integration: A proposed nosology for diagnosis. American Journal of Occupational Therapy, 61(2), 135–140. https://doi.org/10.5014/ajot.61.2.135

Tomchek, S. D., & Dunn, W. (2007). Sensory Processing in Children With and Without Autism: A Comparative Study Using the Short Sensory Profile. American Journal of Occupational Therapy, 61(2), 190–200. https://doi.org/10.5014/ajot.61.2.190

Zingerevich, C., & Patricia D., L. (2009). The contribution of executive functions to participation in school activities of children with high functioning autism spectrum disorder. Research in Autism Spectrum Disorders, 3(2), 429–437. https://doi.org/10.1016/j.rasd.2008.09.002