April is Autism Awareness Month, and according to a 2023 CDC report, 1 in 36 U.S. children under the age of 8 have been diagnosed with autism spectrum disorder (ASD). This rate is four times higher than when the CDC began collecting nationwide data on the disorder in 2000, and statistics show that over 6 million Americans live with the condition. Exponential growth in diagnoses has led to a more robust body of research into potential links between ASD and a variety of possible contributing factors, including dyes, gluten, and food additives. Alongside this research has come increased speculation on medicinal and nutritional interventions among parents looking for answers. Rutgers University in Camden neuroscientist Brian Corbett sees a pressing need to separate scientific evidence from baseless claims.
"Individuals with autism spectrum disorder have more excitatory synapses in their cortical neurons," said Corbett, assistant professor of biology in the College of Arts and Sciences. "This can result in hypersensitivity to sensory information. Imagine if a closing car door sounded like a bomb exploding—it would cause some profoundly detrimental changes in everyday life. Hyperactivity resulting from increased brain activity can lead to seizures, and the prevalence of epilepsy is higher in those with ASD. Even in the absence of seizures, it affects how all information is processed."
Corbett believes increased diagnoses come in part from a better understanding of ASD as a spectrum of related disorders. He also believes that there is more social acceptance and understanding of ASD, so parents might be more willing to have their child diagnosed with a disorder on the spectrum.
“It is similar to how the numbers of COVID cases rose when tests were more widely available,” Corbett said. “A similar number of people had COVID the week before, but it wasn’t reflected in the data.”
As with many complex neurological disorders, many factors can likely contribute to ASD, including genetics. Corbett noted that no environmental factors are widely accepted as being contributing factors to autism in a significant percentage of cases. There is some preliminary evidence, however, that toxins like heavy metals and cigarette smoke might contribute to ASD development in some individuals.
“We're still at the investigating phase,” Corbett said. “In reality, ASD is definitely a complex disorder with many different causes or contributing factors.”
The hormone oxytocin has gained some interest in ASD treatment, since it is particularly important for social behaviors. Oxytocin was shown to improve some social behaviors associated with ASD, according to a study from the Proceedings of the National Academy of Sciences. However, follow-up studies failed to produce the same positive effect on social skills.
“It seems like oxytocin can improve social behaviors in some individuals with ASD, especially those with low oxytocin,” Corbett said. “But again, ASD is complex, with a varied mix of presenting symptoms.”
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