Sources: https://www.hopkinsmedicine.org/health/wellness-and-prevention/the-brain-gut-connection   https://hms.harvard.edu/news/gut-brain-connection-autism   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9355470/   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5005185/   https://www.science.org/doi/10.1126/science.aad0314   If you or someone you know has Autism Spectrum Disorder (ASD), then it wouldn’t be unlikely that whoever has ASD also experiences gastrointestinal issues. Inflammatory bowel disease, diarrhea, and constipation all have been observed to strangely occur in people with ASD. But what’s the reason behind this seemingly random link between a neurological disorder and gastrointestinal issues? The connection might not be as random as you think. In fact, it stems from human anatomy. Within the walls of every human being’s gut are millions of nerve cells that make up the enteric nervous system (ENS). While its main job is to regulate digestion of foods along the digestive system, the ENS has also been described by scientists as a “second brain.” It's described as such partly because of its connection to the central nervous system (CNS), mainly through an outstretching ‘wire’ between the two systems called the vagus nerves.  Additionally, the CNS and ENS share many common neurotransmitters, signaling pathways, and hormones, making one susceptible when the other changes. One common possible example of the connection between the ENS and CNS is the feeling of butterflies in your stomach when you’re nervous. Plus, researchers have found evidence that gastrointestinal issues can influence changes in the mood of an individual. However, keep in mind that the link between the gut and the brain is complex and still largely unexplored, meaning new information could surface at any point in time that changes how we view this connection.  Now that the link between the brain and the gut has been established, what does this have to do with ASD? Research by Harvard Medical School and MIT researchers have found one potential link between infection during pregnancy and both autism-like phenotypes in offspring and experiencing inflammatory problems later in life. They were able to draw conclusions on the link between the two outcomes to the inflammatory signaling molecule interleukin-17a (IL-17a), where IL-17a acting on the fetal brain of mice can induce “autism-like behavioral phenotypes” (Choi et al., 2016) and pups that exhibited intestinal inflammation from mothers with stool from maternal immune activation (MIA) could produce increased IL-17a. Basically, a connection could be made between a common signaling molecule that can lead to both ASD and intestinal inflammation developing. It’s important to note, however, that these experiments were only performed on mice, meaning this isn’t concrete, but hopeful, evidence of this same link occurring in humans. Another fascinating link between ASD and gastrointestinal issues can be found in the fact that the bacteria Clostridium boltae  in the gut can lead to the development of gastrointestinal issues, and Clostridium  bacteria in the colon has been shown to indicate higher risk and severity of ASD.  Although currently there is no concrete connection between ASD and the abnormal gastrointestinal issues those with the disorder may experience, compelling research serves to help find more pieces to help solve this odd bond. And a stronger link established, more effort can be made to better accommodate those with ASD’s needs.

The history of the public’s perception of autism, as well as their understanding, has evolved significantly over time. While the concept of autism was still in its infancy, many psychologists mistook its traits for schizophrenia – for example, in 1938 children suspected to have had autism were described as having “schizoid psychopathy,” and the term “autistic” was coined to describe their “tendency towards solitude and avoidance of other people.” Others suggested that autism came from “refrigerator mothers,” or as theorized by Leo Kanner in 1949: “cold and detached” parents were the root of the condition. Nearly eleven years later in the 1960’s, passionate disagreements between scholars ensued, and the field of autism research was marked by a heated debate between two influential figures - Bernard Rimland and Bruno Bettelheim. Rimland’s theory challenged the prevailing beliefs at the time; he believed that autism was a neurological condition that was not the result of any environmental factors. Rimland's work laid the groundwork for a more nuanced understanding of autism, steering the discourse toward a more scientific exploration of the disorder's biological roots. Rimland’s perspective went head to head with that of Bettelheim, who clung to the belief that the quality of parenting during a child's formative years held the key to managing autism’s behavioral implications. He placed significant emphasis on the role of mothers, much to their resentment and chagrin: The relationship between mothers and psychiatrists soured as mothers believed psychiatrists were making them feel as if they were to blame for their children’s autism. Until the late 90’s, many believed that forms of therapy and support for children with autism were a means of reaching out to a child from within their “autistic shell” and drawing them out. The ideal result was to change a child with autism into a near-“normal” functioning child and eliminate their autistic traits – and thus, the autism self-advocacy movement was born. Autistic self-advocates opposed early autism interventions with a stated treatment goal to “cure” a child with autism. Yet misleading publications regarding the cause of autism remained: In 1998 Andrew Wakefield, M.D. published his paper in the Lancet suggesting that the measles-mumps-rubella (MMR) vaccine triggers autism. Despite the report being retracted and Wakefield having his medical license revoked, the impact of the myth is still felt today and plays a critical part in the platform of the anti-vaccine movement. In the face of these challenges, the autism rights movement, otherwise known as the autistic self-advocacy movement, has expanded to demand tolerance for what they refer to as neurodiversity, garnering support from both neurotypicals and parents of autistic children. But controversy remains. As progress is made in autism research and new data comes out (in 2020 the CDC published that one in 54 children have been identified with having an ASD diagnosis, and research has also been done identifying autism-related genes involved in early brain development) some question the intersectionality of scientific development in the field of autism with autism acceptance  – for example, if we were able to detect an embryo with autism, how would the parents react? All in all, acceptance and providing resources for education about autism should be prioritized above all. As stated by Andrew Solomon in New York Magazine in 2008 neurodiversity activists light the way to such love—a model of social acceptance and self-acceptance that can redeem whole lives. Sources: https://www.verywellhealth.com/autism-timeline-2633213 https://www.frontiersin.org/articles/10.3389/fpsyg.2021.635690/full https://embryo.asu.edu/pages/early-infantile-autism-and-refrigerator-mother-theory-1943-1970 https://www.autism-help.org/points-autism-rights-movement.htm