Recent Advancements in Noninvasive Brain Modulation for Individuals with Autism Spectrum Disorder

SOURCE: Neural Regeneration Research. 18(6) (pp 1191-1195), 2023.


AUTHORS: Griff J.R.; Langlie J.; Bencie N.B.; Cromar Z.J.; Mittal J.; Memis I.; Wallace S.; Marcillo A.E.; Mittal R.; Eshraghi A.A.

ABSTRACT: Autism spectrum disorder is classified as a spectrum of neurodevelopmental disorders with an unknown definitive etiology. Individuals with autism spectrum disorder show deficits in a variety of areas including cognition, memory, attention, emotion recognition, and social skills. With no definitive treatment or cure, the main interventions for individuals with autism spectrum disorder are based on behavioral modulations. Recently, noninvasive brain modulation techniques including repetitive transcranial magnetic stimulation, intermittent theta burst stimulation, continuous theta burst stimulation, and transcranial direct current stimulation have been studied for their therapeutic properties of modifying neuroplasticity, particularly in individuals with autism spectrum disorder. Preliminary evidence from small cohort studies, pilot studies, and clinical trials suggests that the various noninvasive brain stimulation techniques have therapeutic benefits for treating both behavioral and cognitive manifestations of autism spectrum disorder. However, little data is available for quantifying the clinical significance of these findings as well as the long-term outcomes of individuals with autism spectrum disorder who underwent transcranial stimulation. The objective of this review is to highlight the most recent advancements in the application of noninvasive brain modulation technology in individuals with autism spectrum disorder.

CONCLUSION: Overall, the various noninvasive brain stimulation modalities which have been explored in this article show great promise as possible neuromodulators for the treatment of ASD symptoms. Preliminary results from randomized pilot studies suggest that there are many positive effects, which warrant the continuation and development of more trials to fully understand the therapeutic nature of noninvasive brain stimulation in individuals, both children and adults, with ASD.

There are no standardized protocols for administering the various brain stimulating technologies, including the location of stimulation, and there are also no uniform outcome measures amongst studies making it impossible to compare methods and results directly. Nevertheless, the multitude of stimulation protocols and tracked outcome measures indicate that there is a wide realm of possible treatments for the variable expressivity of ASD symptomatology. In addition, studies published thus far have small sample sizes with minimal follow-up. To recognize the true benefits of noninvasive brain stimulation in individuals with ASD, all of the above criteria need to be met which will enable researchers to corroborate their findings.

From the perspective of the patients, it is important for these treatments to be as accessible as possible. Protocols that require daily treatments for extended periods may act as a barrier for patients and their families to receiving the proper brain stimulation. Therefore, keeping the patients??best interests at the forefront can serve to guide the research of treatments for ASD. In addition, efforts should be done to reduce the costs associated with noninvasive brain modulation enhancing accessibility so that more patients can benefit from this technology.