Reducing Auditory Hypersensitivities in Autistic Spectrum Disorder: Preliminary Findings Evaluating the Listening Project Protocol

Abstract

Auditory hypersensitivities are a common feature of autism spectrum disorder (ASD). In the present study, the effectiveness of a novel intervention, the listening project protocol (LPP), was evaluated in two trials conducted with children diagnosed with ASD. LPP was developed to reduce auditory hypersensitivities. LPP is based on a theoretical “neural exercise” model that uses computer altered acoustic stimulation to recruit the neural regulation of middle ear muscles. Features of the intervention stimuli were informed by basic research in speech and hearing sciences that has identified the specific acoustic frequencies necessary to understand speech, which must pass through middle ear structures before being processed by other components of the auditory system. LPP was hypothesized to reduce auditory hypersensitivities by increasing the neural tone to the middle ear muscles to functionally dampen competing sounds in frequencies lower than human speech. The trials demonstrated that LPP, when contrasted to control conditions, selectively reduced auditory hypersensitivities. These findings are consistent with the polyvagal theory, which emphasizes the role of the middle ear muscles in social communication.

Interventions Targeting Sensory Challenges in Autism Spectrum Disorder: A Systematic Review

“…The studies included 20 RCTs, 13 -32 1 nonrandomized trial, 33 and 3 retrospective cohort studies. 34 -36 Three studies had low risk of bias, 21,23,30 10 had moderate risk of bias, 14,15,19,20,22,24,25,27,29,31,32 and 11 (including 1 publication 26 reporting 2 unique RCTs) had high risk of bias. 13, 16 -18, 26, 28, 33 -36 Table 2 outlines the study characteristics and risk of bias assessments.…”

“…15 Two RCTs examined the use of filtered music and reported some parent-rated improvement in hearing sensitivity, spontaneous speech, listening, and behavioral organization after filtered music compared with children in the control condition (P ≤ .05). 26 Across both trials, groups did not differ in the other behavioral domains rated.…”

“…14,15 Two high risk of bias RCTs (reported in a single publication) reported significant parent-rated improvements in hearing sensitivity and behavior (Table 3). 26 One crossover RCT comparing music passed through an electronic ear for attenuation and modulation to commercially produced music reported no statistically significant treatment effects on language skills. 14 Another RCT of auditory integration therapy for children with significant language delays reported no significant benefits of auditory integration.…”

Making the World Safe for our Children: Down-regulating Defence and Up-regulating Social Engagement to ‘Optimise’ the Human Experience

“…Thus, mammals, not only had the ability to express bodily state in voice, but also had a uniquely mammalian middle ear that functionally dampened low-frequency background noise and enabled the processing of specific acoustic cues of social communication (Porges & Lewis, 2009;Porges et al, 2014;Stewart et al, 2013Stewart et al, , 2015.…”

Exercise Alleviates Autism Spectrum Disorder Deficits

“…Finally, in ASD children, auditory modality hypersensitivity presents an important feature of disability. The "listening project protocol" offers a new intervention, a form of 'neural exercise' that applies acoustic stimulation to recruit the neural regulation of the middle ear muscles [34]. Listening project protocol was hypothesized to reduce auditory hypersensitivities by increasing the neural tone to the middle ear muscles to functionally dampen competing sounds in frequencies lower than human speech.…”