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Applied Psychophysiology and Biofeedback

, Volume 41, Issue 4, pp 405–420 | Cite as

Electrophysiological and Behavioral Outcomes of Berard Auditory Integration Training (AIT) in Children with Autism Spectrum Disorder

  • Estate M. SokhadzeEmail author
  • Manuel F. Casanova
  • Allan Tasman
  • Sally Brockett
Article

Abstract

Autism is a pervasive developmental disorder of childhood characterized by deficits in social interaction, language, and stereotyped behaviors along with a restricted range of interests. It is further marked by an inability to perceive and respond to social and emotional signals in a typical manner. This might due to the functional disconnectivity of networks important for specific aspects of social cognition and behavioral control resulting in deficits of sensory information integration. According to several recent theories sensory processing and integration abnormalities may play an important role in impairments of perception, cognition, and behavior in individuals with autism. Among these sensory abnormalities, auditory perception distortion may contribute to many typical symptoms of autism. The present study used Berard’s technique of auditory integration training (AIT) to improve sound integration in children with autism. It also aimed to understand the abnormal neural and functional mechanisms underlying sound processing distortion in autism by incorporating behavioral, psychophysiological and neurophysiological outcomes. It was proposed that exposure to twenty 30-min AIT sessions (total 10 h of training) would result in improved behavioral evaluation scores, improve profile of cardiorespiratory activity, and positively affect both early [N1, mismatch negativity (MMN)] and late (P3) components of evoked potentials in auditory oddball task. Eighteen children with autism spectrum disorder (ASD) participated in the study. A group of 16 typically developing children served as a contrast group in the auditory oddball task. Autonomic outcomes of the study reflected a linear increase of heart rate variability measures and respiration rate. Comparison of evoked potential characteristics of children with ASD versus typically developing children revealed several group difference findings, more specifically, a delayed latency of N1 to rare and frequent stimuli, larger MMN; higher P3a to frequent stimuli, and at the same time delayed latency of P3b to rare stimuli in the autism group. Post-AIT changes in evoked potentials could be summarized as a decreased magnitude of N1 to rare stimuli, marginally lower negativity of MMN, and decrease of the P3a to frequent stimuli along with delayed latency and higher amplitude of the P3b to the rare stimuli. These evoked potential changes following completion of Berard AIT course are in a positive direction, making them less distinct from those recorded in age-matched group of typical children, thus could be considered as changes towards normalization. Parental questionnaires clearly demonstrated improvements in behavioral symptoms such as irritability, hyperactivity, repetitive behaviors and other important behavioral domains. The results of the study propose that more controlled research is necessary to document behavioral and psychophysiological changes resulting from Berard AIT and to provide explanation of the neural mechanisms of how auditory integration training may affect behavior and psychophysiological responses of children with ASD.

Keywords

Autism spectrum disorder Auditory integration Heart rate Respiration Auditory evoked potentials Mismatch negativity 

Notes

Acknowledgments

This study was funded by the Autism Research Institute (ARI, San Diego, CA) pilot research Grant ARI-03.2012 to Estate M. Sokhadze.

Compliance with Ethical Standards

Conflict of interest

The authors do not have any potential conflict of interest to disclose. All authors therefore declare that they do not have any conflict of interests.

Ethical Approval

All procedures performed in this study that involved human subjects were in accordance with the ethical standards of the institutional research committee (IRB) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The protocol of the study was approved by the University of Louisville IRB. Signed informed consent forms (from parents) and informed assent forms (from children) were obtained from all individual participants and parents of children included in the study. The results of the study propose that more controlled research is necessary to document behavioral and psychophysiological changes resulting from Berard AIT and to provide explanation of the neural mechanisms of how auditory integration training may affect behavior and psychophysiological responses of children with ASD.

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Estate M. Sokhadze
    • 1
    • 2
    Email author
  • Manuel F. Casanova
    • 1
    • 2
  • Allan Tasman
    • 2
  • Sally Brockett
    • 3
  1. 1.University of South Carolina School of Medicine-Greenville, Greenville Health SystemGreenvilleUSA
  2. 2.University of LouisvilleLouisvilleUSA
  3. 3.IDEA Training CenterNorth HavenUSA

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