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Probing the Brain in Autism Using fMRI and Diffusion Tensor Imaging
Published on: September 12, 2011
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11C-UCB-J PET imaging is consistent with lower synaptic density in autistic adults
David Matuskey1,2,3,4, Yanghong Yang5, Mika Naganawa5
1Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA. david.matuskey@yale.edu.
Molecular Psychiatry
|October 4, 2024
Summary
Autistic adults show significantly lower synaptic density across the brain, particularly in gray matter, compared to non-autistic individuals. This reduced synaptic density correlates with autism severity, suggesting a potential molecular basis for autism.
Area of Science:
- Neuroscience
- Molecular Psychiatry
- Radiology
Background:
- Autism's molecular underpinnings remain unclear, though synaptopathology is implicated.
- Synaptic vesicle glycoprotein 2A (SV2A) is a key marker for synaptic density.
Purpose of the Study:
- To investigate synaptic density in autistic adults using positron emission tomography (PET) and 11C-UCB-J.
- To explore the relationship between synaptic density and clinical autistic features.
Main Methods:
- 11C-UCB-J PET scans were performed on 12 autistic and 20 non-autistic adults.
- Binding potential (BPND) was calculated, with partial volume correction applied.
- Mixed-model statistics analyzed group differences and correlations with clinical measures.
Main Results:
- Whole cortex synaptic density was 17% lower in autistic individuals (p=0.01).
- 11C-UCB-J BPND was reduced in all brain regions of autistic participants, notably in the prefrontal cortex (-15%, p=0.02) and gray matter.
- Synaptic density correlated significantly with autistic features (r=0.67, p=0.02).
Conclusions:
- This PET study reveals widespread, significant reductions in synaptic density in autistic adults.
- Brain-wide synaptic density may represent a molecular basis for the autism phenotype.
- Lower synaptic density is associated with increased autistic features.
