A groundbreaking study has revealed that autistic individuals possess fewer brain synapses, which correlates directly with more pronounced autism traits, including challenges in social interaction and communication.

Utilizing positron emission tomography (PET) scans, this research represents the first measurement of synaptic density in living autistic individuals, illustrating the connection between brain structure and behavior.

The research found that lower synaptic counts were significantly associated with increased autistic traits, such as reduced eye contact and repetitive behaviors.

McPartland emphasizes that a deeper understanding of the biological mechanisms underlying autism could facilitate the identification of better-defined subgroups and enhance clinical support.

Looking ahead, future research intends to investigate nonradioactive, cost-effective methods for studying the autistic brain and to further understand synaptic development during adolescence.

The study involved 12 autistic adults and 20 neurotypical adults, who were assessed using the Autism Diagnostic Observation Schedule (ADOS) and underwent both MRI and PET scans.

The study employed a novel radiotracer, 11C-UCB-J, which enabled researchers to observe synaptic connectivity in living brains for the first time.

These findings underscore a significant limitation in current autism diagnostics, which often rely on broad behavioral descriptions rather than a biological understanding of the condition.

The research team is also keen to explore the relationship between synaptic density and mental health issues in autistic individuals, aiming to improve their overall quality of life.