The trial was conducted across three academic hospitals in China and led by Hangyu Tan. Researchers enrolled 200 children aged 4 to 10 between July 2023 and October 2024. Half of the participants received accelerated continuous theta burst stimulation, known as a-cTBS. The other half received sham stimulation that buzzed and vibrated but delivered no magnetic pulses. Neither the families nor the clinicians knew which group each child was in.
An intensive five day protocol
The treatment protocol was intensive and children received 10 stimulation sessions per day. These were spaced one hour apart, over five consecutive days, delivering 18,000 magnetic pulses daily.
Since each individual session lasted only a few minutes, the protocol offered a major practical advantage over conventional magnetic stimulation. Younger children often struggle to tolerate longer, still sessions. The device targets the left primary motor cortex by generating a rapidly changing magnetic field. This field passes safely through the skull to activate underlying neurons.
Measurable gains in communication
Children in the active stimulation group showed greater improvements in social communication compared to the sham group. These results were based on a standardized rating scale completed by parents. Crucially, the communication gains remained clearly present at a one month follow-up. Language skills also improved noticeably in the treated group.
The therapy appeared safe, with no serious adverse events reported during the trial. The few minor side effects that did occur resolved quickly on their own without clinical intervention.
A critical methodological caveat
Independent experts reviewing the data have highlighted a significant limitation in how the groups were set up. The active stimulation group entered the trial with higher average difficulty scores than the sham group, scoring 84.28 versus 78.85 on the primary rating scale.
Starting with more severe symptoms gave the treated children more room to show dramatic statistical improvement. This onset imbalance makes it harder to isolate the true impact of the therapy. Future trials must address this limitation through stricter randomization matching.
Expanding therapy
Roughly one in three autistic people also has an intellectual disability, a diagnosis that severely limits available treatment options. Typical neurostimulation studies recruit older children or adults who can follow complex instructions and sit perfectly still. Due to these strict requirements, young children with intellectual disabilities rarely appear in these datasets.
The researchers emphasize that a-cTBS is not a replacement for psychosocial support or educational adaptations. Rather, they view it as a potential tool within a broader, multimodal care plan, provided the results can be replicated in larger, longer-term trials.
