A future where an autism brain scan facilitates accurate, earliest possible diagnoses of autism spectrum disorders may not only be possible but probable.
If only there was a quick, accurate test that could diagnose autism effortlessly, a rapid blood test or brain scan, eliminating the need for doctors to painstakingly examine a child’s developmental history, observing and deciphering behavioral clues.
Diagnosing autism spectrum disorders is often a lengthy procedure and, for accuracy, a multidisciplinary team may be required. Increasingly research is examining the future use of magnetic resonance imaging (MRI) as complimenting current gold standard methods of diagnosis.
Early brain changes and autism spectrum disorder
There are certain aspects of diagnosing autism spectrum disorder (ASD) that may be challenging for professionals (Makino et al., 2021). Since there is no physical test to diagnose this complex neurodevelopmental condition, doctors use behavior, history, and parent-reported interviews to diagnose ASD.
Research is suggesting that, in future, brain scans may be used to diagnose autism, possibly even before behavioral symptoms become apparent. A longitudinal neuroimaging study analyzing data for both high-risk and low-risk children (Hazlett et al., 2017) searched for possible links between the diagnosis of autism at two years, and the appearance of symptoms during the early postnatal period.
In some of the children who were later diagnosed with autism, there were apparent brain changes. Surface area expansion and brain overgrowth were some of the brain changes noticed. Specifically, the authors (Hazlett et al., 2017) found:
- Hyperexpansion of the cortical surface area between the age of 6 and 12 months
- Such expansion preceded brain volume overgrowth observed between the age of 12 and 24 months in high risk infants diagnosed with autism at 24 months of age
- A link was found between brain volume growth and the severity and emergence of autistic social impairments
Findings from the study (Hazlett et al., 2017) show that early brain changes occur during the time frame in which autistic behaviors initially emerge. Another study (Piven et al., 2017) proposed a conceptual framework for early brain and behavior development in autism, which may aid understanding of the timing of developmental brain and behavior mechanisms in autism during the child’s earliest years.
The study (Piven et al., 2017) suggests that an increase in the proliferation of neural progenitor cells and hyper expansion of cortical surfaces during the first 12 months of a child’s life may be a particular pattern of brain development in children who are later diagnosed with autism. These brain changes occur before any symptoms appear, during a time period characterized by disturbed sensorimotor and attentional experience.
The authors’ framework postulates that these changes lead to differing experience-dependent neuronal development and reduced elimination of neuronal processes. This process is associated with brain volume overgrowth and may disrupt refinement of certain brain circuit connections which is linked to autistic social impairment symptoms emerging in the second year of a child’s life ((Piven et al., 2017).
If research and autism brain scans can increase our understanding of how and when differences occur in a young child’s brain, intervention for autism could be more targeted and timely.
Differences in brain
For children and adults with ASD, greater brain volume and growth may not be the only characteristics differentiating the autistic brain. Research, especially brain imaging studies employing MRI scans, has illuminated various areas of difference in the autistic brain.
In which way(s) does the autistic brain look different?
A differently wired brain is often mentioned when referring to autism. Increasingly, studies are showing that there are actual differences in the autistic brain; using MRI, researchers (Sherr et al., 2017) identified structural abnormalities in the brains of individuals with one of the most common genetic causes of autism.
The science behind some of these brain differences may be complicated, but it seems to come down to abnormalities that many people with ASD have, at the 16th chromosome called 16p11.2. At this site, deletion or duplication of a piece of a chromosome may result in one of the most common genetic causes of autism.
The study (Sherr et al., 2017) revealed some interesting brain differences in deletion and duplication carriers in comparison to non-carriers:
- In comparison to non-carriers and control groups, the fiber bundle connecting the left and rights hemispheres of the brain was differently shaped and thicker in the deletion carriers and thinner in the duplication carriers
- Brain overgrowth was apparent in the deletion carriers
- The duplication carriers, on the other hand, displayed features of brain undergrowth
In this study (Sherr et al., 2017) differences in brain structure, visible on brain images, corresponded to behavioral and cognitive deficits. These results may have implications for future diagnosis of autism, if structural brain abnormalities are easily identifiable using brain scans, autism could be identified earlier with more accuracy.
Are brain scans necessary?
As many neurodevelopmental disorders are diagnosed through behavioral evaluations, interviews, symptoms tests, and medical history screening, do we even need brain scans to diagnose autism? Furthermore, considering the sensory processing differences of most children with autism, many parents may wonder about the practicality of using technology like MRI scans.
Heterogeneity and other diagnostic challenges
Autism is inherently heterogeneous and the condition involves plenty of uncertainties that could complicate diagnosis. Furthermore, it occurs on a wide spectrum—as the well-known saying goes: “If you’ve met one individual with autism, you’ve met one individual with autism.” (Dr. Stephen Shore).
As diagnosis for the condition involves behavioral evaluations, a further complication involves masking or camouflaging of symptoms; found especially among females on the spectrum. All these uncertainties and challenges fuel the research for brain biomarkers for neurodevelopmental disorders.
Establishing neuroimaging biomarkers of autism using MRI may be a crucial step for accurate diagnosis and better, tailored treatment. This may be especially important early on in a child on the spectrum’s life when appropriate intervention may have the greatest effect (Pagnozzi et al., 2018).
Practicality of an MRI for children with autism
Reading such encouraging research incites hope for a future where children will be diagnosed and treated at the earliest opportunity ensuring a better quality of life for autistic children. Practically speaking, however, parents may wonder about the feasibility of MRI.
According to Stogiannos et al. (2021): “The noisy, narrow, isolating magnetic resonance imaging environment and long scan times may not be suitable for autistic individuals…” This may be due to communication deficits (a core autism characteristic) sensory processing deficits and/or anxiety.
The study (Stogiannos et al., 2021) aimed to review and identify adaptations for autistic people to undergo MRI scans without needing anesthesia or sedation. Communication techniques, an adaptation of the environment, distraction, and other accommodations are mentioned by the authors in this regard.
Parents, the experts of their autistic child’s sensory and environmental needs, are in the best position to advocate for their children. If brain scans are indeed the future of diagnosing and treating autism, parents will have to educate medical professionals about ways to ensure these technological advancements do not do more harm than good.
As far as doctors are concerned the above-mentioned study (Stogiannos et al., 2021) concludes by mentioning that their research results could be used for training medical professionals to use MRI scanners in a manner that accommodates individuals on the spectrum.
While we wait
A future where every autistic individual has access to advanced technology like MRI scans could mean scientists not only understand the condition better but can also enhance diagnosis and intervention. Currently, however, MRI scans are used predominantly as a research tool rather than a diagnostic one. This may change soon, especially when encouraging study results to tell us that combining data from structural MRI and resting-state functional MRI achieves diagnostic accuracy of over 80% (Dekhil et al., 2019).
For now, the gold standard of diagnosis remains the autism diagnostic observation schedule (ADOS). So while parents wait for earlier, more accurate diagnostic and treatment tools for their children with autism, what can be done to help families through the often traumatic period of seeking and confirming neurodevelopmental disorder diagnoses?
Jamiel Owens, author, speaker, and autism advocate shared his story of receiving his son’s autism diagnosis with me during a Q&A for the upcoming Autism Parenting Summit (April 2022). When asked what sort of support would have made the time when his son was diagnosed easier, Jamiel spoke about the need for doctors to diagnose with compassion.
While he only had good things to say about doctors and the work they do in terms of neurodevelopmental disorders, he did speak passionately about empathy and compassion and how doctors should treat parents whose entire life may change due to their child’s autism diagnosis.
As we come closer to technologically advanced methods of diagnosing and treating autism, let’s hope that optimum diagnostic and intervention tools do not strip compassion from the process.
References:
Dekhil, O., Ali, M., El-Nakieb, Y., Shalaby, A., Soliman, A., Switala, A., Mahmoud, A., Ghazal, M., Hajjdiab, H., Casanova, M. F., Elmaghraby, A., Keynton, R., El-Baz, A., & Barnes, G. (2019). A Personalized Autism Diagnosis CAD System Using a Fusion of Structural MRI and Resting-State Functional MRI Data. Frontiers in psychiatry, 10, 392. https://doi.org/10.3389/fpsyt.2019.00392.
Hazlett, H. C., Gu, H., Munsell, B. C., Kim, S. H., Styner, M., Wolff, J. J., Elison, J. T., Swanson, M. R., Zhu, H., Botteron, K. N., Collins, D. L., Constantino, J. N., Dager, S. R., Estes, A. M., Evans, A. C., Fonov, V. S., Gerig, G., Kostopoulos, P., McKinstry, R. C., Pandey, J., … Statistical Analysis (2017). Early brain development in infants at high risk for autism spectrum disorder. Nature, 542(7641), 348–351. https://doi.org/10.1038/nature21369.
Makino, Amber & Hartman, Laura & King, Gillian & Wong, Pui & Penner, Melanie. (2021). Parent Experiences of Autism Spectrum Disorder Diagnosis: a Scoping Review. Review Journal of Autism and Developmental Disorders. 8. 1-18. 10.1007/s40489-021-00237-y.
Owens, J. (2022). Fatherhood in the Dynamics of Autism. Autism Parenting Summit. Autism Parenting Magazine
Pagnozzi, Alex & Conti, Eugenia & Calderoni, Sara & Fripp, Jurgen & Rose, Stephen. (2018). A systematic review of structural MRI biomarkers in Autism Spectrum Disorder: A Machine Learning perspective. International Journal of Developmental Neuroscience. 71. 10.1016/j.ijdevneu.2018.08.010.
Piven, J., Elison, J. T., & Zylka, M. J. (2017). Toward a conceptual framework for early brain and behavior development in autism. Molecular psychiatry, 22(10), 1385–1394. https://doi.org/10.1038/mp.2017.131.
Sherr, E, M.D., Ph.D et al. (2017). Brain MR Imaging Findings and Associated Outcomes in Carriers of the Reciprocal Copy Number Variation at 16p11.2.. Radiology.
Stogiannos, N., Carlier, S., Harvey-Lloyd, J. M., Brammer, A., Nugent, B., Cleaver, K., McNulty, J. P., Dos Reis, C. S., & Malamateniou, C. (2021). A systematic review of person-centered adjustments to facilitate magnetic resonance imaging for autistic patients without the use of sedation or anaesthesia. Autism: the international journal of research and practice, 13623613211065542. Advance online publication. https://doi.org/10.1177/13623613211065542.
