Functional Brain Asymmetry Reveals Heterogeneous Subtypes in Autism Spectrum Disorder.
Chae Yeon Kim, Sunghun Kim, Bo-Yong Park
Three distinct autism subtypes were identified by brain asymmetry patterns, and the subtype with the most severe social and communication symptoms showed a mixed left-right dominance profile.
This is a neuroimaging finding about brain organization, not a new assessment or treatment.
Key findings
1Compared with typically developing controls, individuals with ASD showed atypical hemispheric asymmetry: left-dominant connectivity in the ventromedial prefrontal cortex, angular gyrus, and superior temporal pole, and right-dominant asymmetry in the visual cortex, dorsomedial prefrontal cortex, and pallidum.
2Clustering the ASD group by asymmetry pattern yielded three subtypes: one with overall rightward asymmetry (described as social-motivational), one with a mixed pattern of leftward dominance in default-mode and frontoparietal networks plus rightward dominance in somatomotor and visual areas (described as cognitive-control/impulsive), and one with overall leftward asymmetry (described as memory-language).
3The mixed-pattern subtype (subtype 2) had significantly higher ADOS total, communication, and social scores than the other two subtypes, and showed greater hubness in the ventrolateral prefrontal cortex and inferior parietal lobule with reduced somatomotor connectivity.
Still to come
How it was doneWhat they found
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The ASD sample was 88.2% male, so the findings may not generalise to autistic women and girls. The study is cross-sectional: it captures a single snapshot of brain asymmetry and cannot say whether these subtypes are stable over time or shift across development. Age was not explicitly controlled in the clustering step, and the authors note that subtype composition could vary across developmental stages. The data came from 19 different imaging sites; although ComBat harmonisation was applied, residual scanner and protocol differences may have influenced the asymmetry estimates. The choice of three clusters, while supported by multiple validity indices, still involves a degree of subjectivity that the authors acknowledge. The subtypes are data-driven statistical groupings from brain imaging; they have not been validated as diagnostic categories and cannot be identified from any clinical assessment a therapist can perform.
Declared interests
Funded by the Korean government (IITP grant 2022-0-00448, NRF grant RS-2025-20253035, and NRF Basic Science Research Program RS-2025-25422106). The authors declare no conflicts of interest.
The easy way to misread this
Do not read the three subtypes as three treatable 'types of autism' that a clinician can identify and target differently. The subtypes were derived from resting-state fMRI asymmetry patterns that no therapist can measure at the bedside, they have not been validated as stable diagnostic categories, and the study is cross-sectional with a heavily male sample. The finding is a research-level description of brain-organisation diversity, not a new clinical framework.
Summarised by AI from the full paper, without a clinician reviewing it. Check it against the source before it changes what you do. Read it on PubMed →