Modifying Classroom Acoustical Environment to Affect Sensory Behaviours and Learning of Children with ASD

This Study examines the correlation between classroom acoustical parameters, sensory response and on-task engagement behaviours of children with Autism Spectrum Disorder (ASD); these behaviours include ear covering, repetitive body movements, loud vocalisation and on-task engagement. The Study takes both qualitative and quantitative approaches. A purposive sample of four male students aged 9 to 11 years with a medical diagnosis of ASD was selected for the Study. The quantitative approach uses Single Case Experimental Design (SCED) with ABA (Withdrawal Design) to investigate the effects of the long and short reverberation time (RT60). Participants were observed during two weeks of baseline (A1-phase), two weeks of acoustic intervention (B- phase) and two weeks of return to the baseline phase (A2- phase), i.e. removal of acoustic intervention. In the qualitative Stage 1 Study, semi-structured expert interviews corroborated the manifestation of sensory response behavioural interlinkage with noise/ acoustics and on-task learning and engagement of children with ASD. In the Stage 2 Study, frequencies of delineated sensory response behaviours were calculated from video-recorded sessions of social group activity of 5 to 10 minutes long under existing and improved acoustical conditions. In the Stage 3 Study, the time of the participants' on-task was calculated in percentage using momentary time sampling from 5 to 10 minutes long video-recorded sessions under existing and improved acoustical conditions. Visual analysis was conducted to measure within-phase, between-phase characteristics and supplementary effect size measure and descriptive statistics were reported. The outcome of the Stage 1 Study shows that noise/acoustics is a significant variable in a classroom environment affecting the sensory behaviours, learning and engagement of children with ASD. In the Stage 2 Study, when the RT60 of the classroom was decreased from 1.11s to 0.39s, the results indicated a positive correlative effect on the overall decrease of repetitive behaviour for all four participants. Ear covering behaviour, the outcome was largely positive; results were promising among three out of four participants, indicative of a positive correlation. Loud vocalising behaviour, the outcome for two out of four participants, was indicative of a strong impact of acoustic intervention across the three markers, visual analysis, non-overlapping percentage, and descriptive mean values, suggesting an overall decrease in loud vocalising behaviour during Phase B intervention. For two of the participants, the outcomes for loud vocalisation were indeterminate due to their idiosyncratic trend findings. In the Stage 3 Study, overall, the results drew a strong positive co-relationship across the four participants under short RT (0.39s). Children's performativity depicted a significantly higher percentage increase in on-task intervals during 1:1 learning sessions under the improved acoustical condition. The collated data analysis results were significantly suggestive through its validation that the sensory behaviour modulation of the participating children with ASD was considerably influenced by classroom environment acoustical modification through intervention which is an important factor in their learning and behaviour.