Sensory integration, now trademarked as Ayres Sensory Integration^® or ASI, is based on principles of neuroscience and provides a framework for understanding the contributions of the sensory and motor foundations of human behavior. The theory and practice of ASI continues to evolve as greater understanding of the neurobiology of human behavior emerges. In this paper we examine core constructs of ASI identified in the seminal work of Dr. Jean Ayres, and present current neuroscience research that underlies the main patterns of sensory integration function and dysfunction. We consider how current research verifies and clarifies Ayres’ propositions by describing functions of the vestibular, proprioceptive, and tactile sensory systems, and exploring their relationships to ocular, postural, bilateral integration, praxis, and sensory modulation. We close by proposing neuroplasticity as the mechanisms underlying change as a result of ASI intervention.

Comprehensive, reliable, and valid assessment is essential for individually tailored, appropriate, and effective intervention planning and implementation. Research, education, and practice using an Ayres Sensory Integration^® (ASI) approach have a long history of prioritizing comprehensive assessment. To meet the need for a set of tests that will fully evaluate the constructs of ASI with psychometrically strong, internationally appropriate, and easily accessible measurement tools, the development of the Evaluation in Ayres Sensory Integration^® (EASI) has been initiated. This article introduces the EASI, describes the overarching plan for its development, and reports the results of promising preliminary analyses of discriminative validity data.

Background: Differences in responding to sensory stimuli, including sensory hyperreactivity (HYPER), hyporeactivity (HYPO), and sensory seeking (SEEK) have been observed in autistic individuals across sensory modalities, but few studies have examined the structure of these “supra-modal” traits in the autistic population. Methods: Leveraging a combined sample of 3868 autistic youth drawn from 12 distinct data sources (ages 3–18 years and representing the full range of cognitive ability), the current study used modern psychometric and meta-analytic techniques to interrogate the latent structure and correlates of caregiver-reported HYPER, HYPO, and SEEK within and across sensory modalities. Bifactor statistical indices were used to both evaluate the strength of a “general response pattern” factor for each supra-modal construct and determine the added value of “modality-specific response pattern” scores (e.g., Visual HYPER). Bayesian random-effects integrative data analysis models were used to examine the clinical and demographic correlates of all interpretable HYPER, HYPO, and SEEK (sub)constructs. Results: All modality-specific HYPER subconstructs could be reliably and validly measured, whereas certain modality-specific HYPO and SEEK subconstructs were psychometrically inadequate when measured using existing items. Bifactor analyses supported the validity of a supra-modal HYPER construct (ω_H = .800) but not a supra-modal HYPO construct (ω_H = .653), and supra-modal SEEK models suggested a more limited version of the construct that excluded some sensory modalities (ω_H = .800; 4/7 modalities). Modality-specific subscales demonstrated significant added value for all response patterns. Meta-analytic correlations varied by construct, although sensory features tended to correlate most with other domains of core autism features and co-occurring psychiatric symptoms (with general HYPER and speech HYPO demonstrating the largest numbers of practically significant correlations). Limitations: Conclusions may not be generalizable beyond the specific pool of items used in the current study, which was limited to caregiver report of observable behaviors and excluded multisensory items that reflect many “real-world” sensory experiences. Conclusion: Of the three sensory response patterns, only HYPER demonstrated sufficient evidence for valid interpretation at the supra-modal level, whereas supra-modal HYPO/SEEK constructs demonstrated substantial psychometric limitations. For clinicians and researchers seeking to characterize sensory reactivity in autism, modality-specific response pattern scores may represent viable alternatives that overcome many of these limitations.

Importance: Vestibular and proprioceptive functions play a critical role in occupational performance and participation. Assessment of these functions in a reliable and valid manner is part of a comprehensive assessment in the Ayres Sensory Integration® frame of reference, commonly applied in pediatric occupational therapy. Objective: To report on reliability and validity of six tests of vestibular and proprioceptive functions of the Evaluation in Ayres Sensory Integration (EASI). Design: We used Rasch analyses to examine and modify the number of items and scoring categories on the six tests and known-groups analysis to examine group differences. We evaluated internal consistency using Cronbach’s α and Rasch person reliability. Participants: The sample contained typically developing children (n = 150) and children with sensory integration concerns (n = 84); all participated voluntarily. Outcomes and Measures: The EASI is used to measure sensory and motor functions in children ages 3 to 12 yr. The six tests of vestibular and proprioceptive functions were analyzed in this study. Results: Data from >96% of items conformed to the expectations of the model. We found statistically significant group differences (ps < .001–.128; ds = 0.20–1.31), with the typically developing children group scoring significantly higher on all but one test, and moderate to strong evidence of internal consistency (Rasch person-reliability indices ≥ 0.80; strata > 3) for five of six tests. Conclusions and Relevance: The EASI vestibular and proprioceptive tests have strong construct validity and internal reliability, indicating that they are psychometrically sound clinical measures. What This Article Adds: The development of occupational therapy assessments with strong psychometric properties, such as the EASI tests of vestibular and proprioceptive functions, enhances clinical practice and research by elucidating the factors affecting participation in accurate and dependable ways so that occupational therapy interventions can be focused and effective.

There are two possible outcomes: If the result confirms the hypothesis, then you’ve made a measurement. If the result is contrary to the hypothesis, then you’ve made a discovery.—Enrico Fermi (cited in Jevremovic, 2005, p. 397) Scientific theory evolves through phases. Scientists observe phenomena, classify their observations, examine and explain causation, and attempt to understand their results in varied circumstances. If anomalies are found that do not mesh with the theory, revision occurs, and the theory is improved (Christensen, Carlile, & Sundahl, 2001). Each stage requires accurate and precise measurement and, therefore, appropriate measurement tools.

This article explores the use of the postrotary nystagmus (PRN) test for children younger than current norms (children 4.0 yr–8.11 yr). In the first study, 37 children ages 4–9 yr were examined in the standard testing position and in an adult-held adapted position to determine whether holding a child affected the reflex. Because the position did not affect the reflex, in the second study, PRN in 44 children ages 2 mo–47 mo was compared with published normative mean raw scores for 44 children age 5 yr to determine whether norms for older children were applicable to younger children. No statistically significant differences were found between <4-yr-old and 5-yr-old children, suggesting that the PRN test can be used in infants and toddlers with valid comparison to current norms for 4-yr-olds on the Sensory Integration and Praxis Tests (4.0 yr–8.11 yr). Future research exploring the predictive value of this measure is warranted.