ICD-10: F84.0 | ICD-11: 6A02 | Prevalence: ~1 in 36 children (US, 2023)
Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental condition defined by persistent differences in social communication and by restricted or repetitive behaviors and interests[1]. Although ASD is not a neurodegenerative disease, it intersects with NeuroWiki because many of the implicated pathways, including synaptic transmission, epigenetic regulation, and circuit development, overlap with mechanisms studied across neurologic disease[1:1][2].
ASD represents a spectrum of conditions characterized by:
ASD prevalence has increased significantly over recent decades, attributed to broader diagnostic criteria, increased awareness, and potential environmental factors[1:2][3]:
Risk factors for ASD include[1:3][3:1]:
Several monogenic causes of ASD have been identified[4][5]:
| Gene | Function | Phenotype |
|---|---|---|
| FMR1 | Fragile X mental retardation protein | Intellectual disability, macroorchidism |
| SHANK3 | Synaptic scaffolding | Speech/language deficits |
| NRXN1 | Cell adhesion molecule | Variable neurodevelopmental phenotypes |
| CNTNAP2 | Neurexin family | Language regression, seizures |
| 16p11.2 | Chromosomal deletion | Variable expressivity |
Genome-wide studies have identified hundreds of common variants with small effect sizes, collectively contributing to ASD risk[4:1]:
Pathogenic CNVs account for 10-20% of simplex ASD cases[4:2]:
Synaptic pathology is a central feature of ASD[2:1][^6]:
Postsynaptic density abnormalities:
Presynaptic alterations:
The E/I balance hypothesis posits that ASD involves altered ratio of excitatory to inhibitory signaling[2:2][^6]:
Increasing evidence supports immune dysfunction in ASD[7][8]:
Epigenetic mechanisms contribute to ASD pathogenesis[^9]:
Several genes implicated in ASD also play roles in neurodegenerative diseases[4:3][^10]:
| ASD Gene | Neurodegenerative Relevance |
|---|---|
| FMR1 | Fragile X-associated disorders |
| SHANK3 | Linked to Rett syndrome |
| NRXN1 | Interacts with α-synuclein |
| MAPT | Associated with tauopathies |
ASD frequently co-occurs with[1:4][3:2]:
The synaptic protein networks implicated in ASD overlap with those affected in AD, PD, and ALS[^10]:
Evidence-based behavioral treatments include[1:5][3:3]:
No drugs treat core ASD symptoms, but medications address co-occurring conditions[1:6][^11]:
| Target | Medications | Indication |
|---|---|---|
| Irritability/ aggression | Risperidone, aripiprazole | FDA-approved for ASD |
| ADHD symptoms | Stimulants, atomoxetine | Attention/impulsivity |
| Anxiety | SSRIs | Anxiety/OCD features |
| Seizures | Antiepileptics | Epilepsy |
Novel approaches under investigation include[11][12]:
This section highlights recent publications relevant to this disease.
"Am I My Sibling's Keeper?": the Lived experiences of adult siblings of individuals with Autism Spectrum Disorder in China. ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎
VaeTF-A community-aware perceptual architecture for detecting autism spectrum disorders using fMRI. ↩︎ ↩︎ ↩︎
Eating behaviours of children with ASD: Associations with parental stress, perceived symptom severity, and parenting style in a sample from Türkiye. ↩︎ ↩︎ ↩︎ ↩︎
GIN-transformer based pairwise graph contrastive learning framework. ↩︎ ↩︎ ↩︎ ↩︎
Knowledge, support, and networking for Phelan-McDermid syndrome: a study protocol. ↩︎