areviewofneurobiologyinasd

[areviewofneurobiologyinasd]

Autism Spectrum Disorder (ASD)-An Overview of the Symptomatology, Etiology, Risk Factors, and current Treatments and future aims

Title: Autism Spectrum Disorder (ASD)-An Overview of the Symptomatology, Etiology, Risk Factors, and current Treatments and future aims  

         Autism Spectrum Disorder (ASD) is a neurological condition  comprising several different disorders (DiCicco–Bloom et. al, 2006) associated with a wide spectrum of symptoms of varying extents that include impaired motor skills, rigid thinking, a high sensitivity to certain sensory stimuli, and impairment in the development of social and emotional skills. Overall, people with autism behave, learn, and perceive the world in ways that differ from the norm (Centers for Disease Control and Prevention, 2022). ASD symptoms typically appear before age 3 and most diagnoses happen before this time (Sauer et al., 2021).

 Autism is not a disease and has neither a cure nor effective (medicinal) treatment options. Rather, autism is a neurological condition, specifically a neurodevelopmental disorder (Centers for Disease Control and Prevention, 2022), which can be very disabling. Most healthcare targeted at individuals with autism spectrum Disorder aims to minimize the outward signs associated with the disorder--which can include stimming, struggling to regulate the volume of one's voice, and having meltdowns in situations where one is exposed to intense sensory stimuli. ABA therapy–or Applied Behavioral Analysis– which involves correcting behavior viewed as abnormal in young children and teens with autism–is one of the most commonly used and most controversial treatment options for the disorder. Healthcare professionals who incorporate therapies, such as Applied Behavioral Analysis (ABA) Therapy–which research has established can be very harmful to young people with ASD when applied too forcefully–into supporting kids with autism, may cause long-term harm to the psychological and emotional health of these children/teens. 

Risk factors for developing autism include having a sibling with autism, having particular genetic/chromosomal disorders. being born to older parents, maternal infection, and experiencing birth of pregnancy complications (Centers for Disease Control and Prevention, 2022).

        Past research has examined the neurobiological markers, molecular mechanism, and genes that may be implicated in the etiology of autism spectrum disorder. A review article focusing on the brains of individuals with autism suggests that abnormal brain growth and development in the early postnatal years contributes to symptoms associated with autism (DiCicco–Bloom et. al, 2006). Functional structural, and metabolic neuroimaging have shed light on helping characterize several levels of brain disorder associated with ASD (DiCicco–Bloom et. al, 2006),. Overall, the postnatal brain growth trajectory is greatly increased(DiCicco–Bloom et. al, 2006), (particularly in the early years) for individuals with ASD with the greatest differences in brain growth seen in the rostral cerebral cortex, the amygdala, and cerebellar hemispheres with a greater difference in white versus gray matter generation observed (DiCicco–Bloom et. al, 2006). More recent research studies may shed greater light on the neurobiology of ASD. Focus has recently shifted to identifying risk factors associated with autism, particularly genetic and environmental risk factors. 

Autism Spectrum Disorder is believed to show a concordance of over 90% heritability in both monozygotic and dizygotic twins (DiCicco–Bloom et. al, 2006), with a consensus among researchers that autism is primarily influenced by genetic rather than environmental factors. A review article published in 2021 reviews many promising results, including discussing genome wide association studies that have been used to recover nearly 100 candidate genes in autism spectrum disorder. Past studies modeling genetic transmission of ASD from parent to child suggest polygenism involving approximately 3-15 alleles (implicated in ASD) transmitted from parent to child on average. (Risch et al., 1999; Szatmari, 1999; DiCicco–Bloom et. al, 2006). 

Finally, it is important to clarify that ASD is a spectrum disorder. Therefore, not all individuals diagnosed with the disorder show the exact same symptomatology or the same severity of symptoms. Generally, individuals with autism are characterized as having high or low support needs–descriptions that have replaced outdated functioning labels (high or low-functioning) in recent years. Males are significantly (four times (Sauer et al., 2021)) more likely than females to be diagnosed with autism (Tsirgiotis et al., 2024), however, the symptoms of ASD are believed to present differently in girls and women (Tsirgiotis et al, 2024). This theory indicates a need for further research to shed light on the manner by which key symptoms associated with autism spectrum disorder may present differently in females, particularly in female children  and those without a formal diagnosis (Tsirgiotis et al., 2023b). It is also very possible that societal norms limit particular behaviors (particularly ones that are loud, risky, or viewed as non-conforming) in (even very young) girls with autism more than in boys. Early-intervention for children diagnosed with ASD, typically involving speech and various behavioral therapies, can be effective in helping young people with autism build friendships, discover their interests, and overall enhance their quality of life (DiCicco–Bloom et. al, 2006). Additionally, more research into the long-term effects of Applied Behavioral Analysis–a common behavioral therapy employed among autistic children and teens (although often not by trained medical professionals)–is necessary so as to protect the psychological and emotional well-being of people with autism. 

References: 

Centers for Disease Control and Prevention. (2022b, December 9). What Is Autism Spectrum disorder? Centers for Disease Control and Prevention. https://www.cdc.gov/ncbddd/autism/facts.html

DiCicco-Bloom, E., Lord, C., Zwaigenbaum, L., Courchesne, E., Dager, S. R., Schmitz, C., Schultz, R. T., Crawley, J., & Young, L. J. (2006). The Developmental Neurobiology of Autism Spectrum Disorder. Journal of Neuroscience, 26(26), 6897–6906. https://doi.org/10.1523/JNEUROSCI.1712-06.2006

Sauer, A. K., Stanton, J. E., Hans, S., & Grabrucker, A. M. (2021, August 20). Autism Spectrum Disorders: Etiology and Pathology (A. M. Grabrucker, Ed.). PubMed; Exon Publications. https://www.ncbi.nlm.nih.gov/books/NBK573613/

Tsirgiotis, J. M., Young, R. L., & Weber, N. (2023b). A comparison of the presentations of males and females with autism spectrum disorder and those narrowly below the diagnostic threshold. Autism, 28(4). https://doi.org/10.1177/13623613231190682

**Citations in APA version 7 (latest)