Effectiveness of Noise-Attenuating Headphones for Children With Autism Spectrum Disorder

PURPOSE: Children with autism spectrum disorder (ASD) often demonstrate atypical responses to auditory stimuli in the environment (Stiegler & Davis, 2010). Such responses can increase stress and overall arousal levels, affecting occupational performance. Families of children with ASD report that their children experience increased stress and avoid engaging in essential tasks in overstimulating environments (Pfeiffer et al., 2017). There are a number of methods to create more optimal auditory environments, including the use of noise-attenuating headphones (NAH). Although this is often a low-cost and easily implemented intervention, there is minimal research documenting its effectiveness. The purpose of this study was to examine the effectiveness of two types of NAH in reducing stress in children with ASD in natural environments.

METHOD: A single-case study design with randomization to sequence of intervention (ABAC or ACAB) was used to test the effectiveness of two NAH. Six children aged 8–16 diagnosed with ASD completed the study and were randomly assigned to two groups (G1 and G2) for different phase sequences. An occupational therapy evaluation was completed to identify the presence of auditory processing and daily activities and environments that were avoided or that caused stress based on the type or amount of auditory stimuli.

Five points of data were collected in the four phases of baseline, Intervention 1, washout, and Intervention 2. Participants were provided with a set of Bose (Bose Corp., Framingham, MA) over-ear and in-ear NAH for the intervention phases. Physiological data of heart rate and electrodermal responses (nonspecific skin conductance response [NS–SCR] and skin conductance level [SCL]) were collected using an Empatica (Cambridge, MA) wireless wearable device to measure arousal state. Momentary assessment data were collected on type of daily activity and environmental stimuli. Smartphone technologies collected decibel readings two times in each session and a visual scan of the environment.

Moeyaert’s model parametrization, a multilevel hierarchical linear random effect model, was used to evaluate treatment effects (Manolov & Moeyaert, 2017). This quantitative analysis approach accounts for autocorrelations among observations because of repeated measurements from the same participants while also taking into consideration individual variations.

RESULTS: Participants had significantly lower NS–SCR scores (G1, 15.67, p < .001; G2, 33.65, p < .001) during the intervention phases compared with baseline. The levels of NS–SCR scores did not differ (G1, 0.35, p = .557; G2, 2.07, p = .151) between over-ear and in-ear phases. SCL scores were significantly lower (G2, 238.04, p < .001) during the intervention phases compared with baseline for a random subsample. SCL scores were similar (G1, 0.00, p = .979; G2, 0.04, p = .845) between different intervention phases. Participants had lower heart rates (G1, 23.87, p < .001; G2, 111.23, p < .001) during intervention phases compared with baseline, in particular during the in-ear intervention (G1, 23.66, p < .001; G2, 43.29, p < .001). Further analyses showed that the interventions may have had moderating effects on the relationships between environmental noises and physiological responses, in particular NS–SCR (3.34, p = .067) and SCL (2.83, p = .092) levels.

CONCLUSION: Results provide preliminary evidence for the use of NAH to reduce or maintain physiological arousal levels in stimulating environments for children with ASD. Generalization is limited because of the single-case approach. Findings provide important information to guide treatment planning for occupational therapy practitioners when integrating environment-based interventions such as NAH in natural settings.

References

Manolov, R., & Moeyaert, M. (2017). Recommendations for choosing single-case data analytical techniques. Behavior Therapy, 48, 97–114. https://doi.org/10.1016/j.beth.2016.04.008

Pfeiffer, B., Coster, W., Snethen, G., Piller, A., Derstine, M., & Tucker, C. (2017). Caregivers’ perspectives on the sensory environment and participation in daily activities of children with autism spectrum disorder. American Journal of Occupational Therapy, 71, 7104220028. https://doi.org/10.5014/ajot.2017.021360

Stiegler, L. N., & Davis, R. (2010). Understanding sound sensitivity in individuals with autism spectrum disorders. Focus on Autism and Other Developmental Disabilities, 25, 67–75. https://doi.org/10.1177/1088357610364530