What we could have known since 1986: The overlooked connection between sensory integration and ADHD

Today, children with attention deficit disorder are quickly diagnosed with ADHD. We must be aware that this diagnosis says nothing about the causes or mechanisms of development—it is purely a description of symptoms. What if, in some of these children, sensory integration dysfunctions are the basis of their attention problems? As early as 1986, a small but remarkable study provided clues that could have influenced the general understanding of ADHD and treatment approaches... had it reached the mainstream.

1986: ADHD, Ritalin and sensory testing

In her study, occupational therapist Judith Kimball examined 17 boys who had previously been medically diagnosed with ADHD and classified as good or poor responders to methylphenidate (Ritalin). The children were assessed in the "off-drug" state using Ayres' sensory integrative function tests—including vestibular tests, balance reactions, and tactile perception.

The study produced two interesting results that could have been groundbreaking:

1. Half of the ADHD children were good Ritalin responders.

2. Two sensory patterns emerged that could be clearly assigned to the good and poor responders.

Sensory testing—before Ritalin is prescribed—could reveal who will respond well to the medication and who won't. Do you know of a clinic or practice where this is done?

Now to the two sensory patterns that Kimball found that go hand in hand with whether a child responds positively to Ritalin:

Two types of hyperactivity due to different vestibular processing

Kimball's study suggested that there are at least two neurophysiological types of "hyperactive" children:

1. Under-aroused children with vestibular hyposensitivity who respond well to Ritalin.

2. Children with impaired cortical inhibition who do not benefit from Ritalin and have other causes for their behavior. They showed prolonged nystagmus, poorer balance, and poorer tactile two-point discrimination in the study.

The association of sensory modulation disorders with attention deficits, excitability, and impulsivity has been recognized in ASI theory for many years, but a clear understanding of the relationship between sensory modulation disorders and ADHD has proven elusive.

Particularly intriguing: Kimball argues that the good Ritalin responders are precisely the children who also benefit from ASI therapy—with the difference that this therapy is playful, child-centered, and free of side effects. Or rather, it has numerous positive "side effects"! Numerous studies have shown that vestibularly hyporeactive children – the sensory pattern of good Ritalin responders – respond well to ASI therapy, starting with Ayres (1978), Morrison (1986), Ottenbacher (1982), Kimball (1990), Blanche & Cermak (2023) and Blanche, Test & White (2025), to name just a few.

Although Kimball's study in the 1980s provided these surprising findings, these clues were not taken up, replicated, or used as a guide to diagnosis and treatment of ADHD. The topic remained unmentioned in medical literature and treatment practice for a long time. This wasn't because there was no further evidence—because there is:

• Lane et al. (2010) examined neuroendocrine, electrodermal, and behavioral features in 6- to 12-year-old children with ADHD and sensory hypersensitivity. The results suggested that ADHD should be considered in conjunction with anxiety and sensory reactivity. Based on these biological markers, they argued that there are sensory subgroups within the ADHD diagnosis.

  
  

• In a systematic review, Ghanizadeh (2011) showed consistent evidence of sensory abnormalities in ADHD, both in perception and modulation.

• Isaac et al. (2017) provided a strong physiological argument for the link between vestibular hyposensitivity and attention problems. In their study of 13 children with ADHD and 13 control children, the ADHD group showed a significantly reduced vestibular reflex (cVEMP) . The lower the vestibular activity, the more severe the sensory and attention difficulties. The authors concluded that vestibular hypofunction may contribute to the typical symptoms of ADHD.

• Nunes et al. (2022) confirmed that children with ADHD are significantly more likely to have sensory hypersensitivity and hyposensitivity.

• Delpont et al. (2023) went even further: They demonstrated that the severity of ADHD symptoms increases with the extent of sensory dysfunction – a strong argument for a causal relationship.

  
  

These studies objectively support what we have long observed in practice: children with attention problems often have sensory integration disorders, especially vestibular hyporeactivity .

Why has diagnostic and therapeutic practice not changed?

Since the 1980s, medical research has increasingly focused on pharmacology and clearly manualized diagnoses. Sensory integration is considered "soft," difficult to measure, and not marketable. A therapeutic approach that relies on children's play, joy of movement, and neurophysiological maturation does not fit into this system of hard facts and data.

That's precisely why this debate is so explosive today: We have the evidence, but it simply hasn't been accepted in the mainstream. Meanwhile, every day we see children with attention deficit disorder whose underlying sensory issues, along with all their other negative effects on psychological development and activity performance, are overlooked, and who instead have to accept the side effects of medication. After all, around 50% of children with ADHD have SI disorders.

What does this mean for us today?

Given that the link between vestibular dysfunction and ADHD has been repeatedly demonstrated, and that approximately 50% of children with attention deficit disorder (the proportion in Kimball's sample) have sensory integration disorders, we urgently need to consider this possibility. Ayres' SI therapy (ET-ASI) may represent a viable alternative or complement to medication for precisely these children.

We are not talking about "either/or" here, but rather a differentiated approach: first assess the sensory aspects, then prescribe appropriate therapy.

Conclusion: Time to take a closer look and draw conclusions

The Kimball study may be old, but its insightful potential is highly relevant. It reminds us that behavior always has a cause—and that we as doctors, psychologists, and therapists would do well to take a closer look before making diagnoses and treating symptoms. Because all too often, the answer lies not in behavioral control at the cortical level, but much deeper—in the vestibular system. And a therapy that addresses this issue would bring much more to the lives of affected children than simply treating symptoms.

References

(Exceptionally, the references are arranged chronologically, as this emphasizes the content of the article.)

Ayres, A. J. (1978) . Learning disabilities and the vestibular system. Los Angeles, CA: Western Psychological Services.

Ottenbacher, K.J. (1982). Evaluation of sensory integration therapy: A single-subject time-series analysis. American Journal of Occupational Therapy, 36 (9), 571-578. https://doi.org/10.5014/ajot.36.9.571

Morrison, R. (1986). The effect of sensory integration therapy on vestibular function and visual-motor performance in children with reading disability (Unpublished master's thesis). University of Southern California, Los Angeles, CA.

Kimball, J.G. (1990) . Sensory integration frame of reference: Postulates regarding change and application to practice. American Journal of Occupational Therapy, 44 (6), 499-507. https://doi.org/10.5014/ajot.44.6.499

Ghanizadeh, A. (2009). Can behavioral sensory processing problems guide us to a better understanding of ADHD? International Journal of Psychiatry in Clinical Practice, 13 (4), 273–279. https://doi.org/10.3109/13651500903277971

Lane, S. J., Reynolds, S., & Thacker, L. (2010). Sensory over-responsivity and ADHD: Differentiating using electrodermal responses, cortisol, and anxiety. Frontiers in Integrative Neuroscience, 4 , 8. https://doi.org/10.3389/fnint.2010.00008

Ghanizadeh, A. (2011). Sensory processing problems in children with ADHD, a systematic review. Psychiatry Investigation, 8 (2), 89-94. https://doi.org/10.4306/pi.2011.8.2.89

Isaac, V., Olmedo, D., Aboitiz, F., & Delano, PH (2017). Altered cervical vestibular-evoked myogenic potential in children with attention deficit and hyperactivity disorder. Frontiers in Neurology, 8 , 90. https://doi.org/10.3389/fneur.2017.00090

Nunes, CC, Rego, GG, Oliveira, FSR, Nunes, MR, & Miranda, DM (2022). Sensory processing in children and adolescents with attention deficit hyperactivity disorder. Frontiers in Psychiatry, 13 , 921149. https://doi.org/10.3389/fpsyt.2022.921149

Blanche, E.I., & Cermak,, S.A. (2023) . Hyporesponsiveness to Vestibular Input and Academic Performance . In EA Pyatak & ES Lee (Eds.), 50 Studies Every Occupational Therapist Should Know (Vol. 11, p. 193).

Delpont, M., Ringuenet, D., & Barthelemy, C. (2023). Sensory processing abilities and their impact on disease severity in ADHD. Journal of Personalized Medicine, 13 (5), 786. https://doi.org/10.3390/jpm13050786

Blanche, DK, Test, L., & White, B. (2025) . The influence of vestibular processing on attention and school performance: A case study. Florida OT Association Newsletter; accessed October 9, 2025: https://www.flota.org/index.php?category=sis-article&id=104%3Athe-impact-of-vestibular-processing-on-attention-and-school-performance-a-case-study&option=com_dailyplanetblog&view=entry