Randomised controlled study of inter-hemispheric electroencephalographic coherence following assisted therapy with dolphins in children with autism spectrum disorders

Introduction. Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with impairments in executive function, language, emotional function, and social function. Its anatomofunctional substrate is related to a disorganization of the brain's functional connections. The aim is to investigate the cerebral connections in subjects with ASD through the analysis of the interhemispheric coherence (IHC) of the quantified electroencephalogram and its changes after dolphin assisted therapy (DAT) versus therapeutical intervention without dolphins (TIWD). Patients and methods. The IHC was determined in 44 subjects with ASD before randomly assigning them to two therapeutic groups: DAT (n = 22) and TIWD (n = 22). The results were statistically analyzed through the multi-measure ANOVA test for within-subject (time) and between-subject (DAT vs TIWD) factors. Results. The IHC showed a significant reduction (p < 0.05) for both groups in the delta, theta, beta, and alpha frequencies (p < 0.001) in the anterior frontal region (F3-F4), alpha in the central region (C3-C4) (p < 0.05), and alpha (p < 0.05) and beta (p < 0.001) in the temporal region (T3-T4). In the intersection with the specific treatment (DAT), the coherence in the alpha band increased in Fp1-Fp2 (p < 0.05), and the delta did not decline in F3-F4 (p < 0.05). Conclusion. In 5-year-old children with ASD, DAT increases the IHC in the anterior frontal region and stabilizes the tendency to reduce the delta band in the posterior frontal region.