The Relationship Between Neurobiology and Neurodivergence
Prefrontal Cortex
The prefrontal cortex is known to be the center of emotional regulation and this includes attention and inhibition. Thus ADHD, which is known to be a symptom characterized by a failure of emotional regulation, was the naturally correlated symptom that was investigated within the context of prefrontal cortex shape difference. For ADHD people, the prefrontal cortex was known to be smaller in size, and was also known to activate less. This is because of
neurotransmitter imbalances.
Hippocampus
The hippocampus is in charge of memory and learning, cognitive mapping, and social interactions. The neurodivergent symptom associated with the hippocampus is autism, or more specifically, the autism spectrum disorder (ASD). Unlike the ADHD and neurobiology of the prefrontal cortex, the hippocampus's size is different per individual. What is known though is that gene expression and subsequent neurodevelopment is the reason why the hippocampus is different in individuals with ASD.
Amyglada
The amygdala is also a part of the brain that interacts with autism. Additionally, the amygdala doesn’t work in isolation, but with other portions of the brain. As the amygdala actions involve emotional and social processing, and its correlated symptom is anxiety, which arises from fear processing and social cues. In individuals with autism, the amygdala is large, having been subject to accelerated development at a young age. However, in individuals with anxiety, the size is actually smaller, leading to hypotheses of different external factors being behind the reason for the size difference.
Cerebellum
The cerebellum is linked to motor control, social interaction, and cognitive thinking. As such, some neurodivergent individuals may have some difficulty regarding their motor skills. From a cognitive perspective, the cerebellum is heavily involved with language development and communication skills, and thus its related neurodivergent symptoms are ASD and ADHD. Although the size is the same in the case of the cerebellum, closer inquiries revealed damaged dopamine receptors (Parkinson’s Foundation, 2019).
More often than not, it is not only a single portion of the brain that is different, because the brain’s portion works together in a coordinated manner, as can be seen with the prefrontal lobe and the amygdala. Additionally, due to the difficulties of working neurobiological research and neurodivergent symptoms, information regarding the topic is still being developed at a slower rate compared to other cognitive related disorders.
ADHD & PD: The basal ganglia and cerebellum connection. (2019, January 22). Parkinson’s Foundation.
https://www.parkinson.org/blog/science-news/adhd
Neuroanatomy: The Basics - Dana Foundation. (2025, October 23). Dana Foundation.
https://dana.org/resources/neuroanatomy-the-basics/
Introduction
In the past century, the field of neurodivergence focused on regulating the emotions of a person, and it was in the latter half of the 20th century, where biochemical (monoamine) focused medication was prescribed to address the chemical imbalances that occurred in the human brain. This coincided with the reestablishment of neurodivergent symptoms and the advancement of medication.
Greater research in the field of neurodivergence medication eventually hinted at a close relationship with the neurobiology of the brain. In retrospect, it made so much sense! For example, I talked about how both SSRI and SNRI were used to address monoamine reabsorption in the brain, so naturally, further inquiry would deal with how the brain morphology might have brought about the differences between neurodivergent people and neurotypical people.
Portions of the Brain Worth Noting
(Dana Foundation, 2025)
When comparing the neurobiological difference that arises between neurodivergent people and neurotypical people, researchers often focus on the difference between the size of a portion of the brain, and its activation frequency. That is why many science reports often conclude with an analysis of those two variables.