ClinicalTrials.gg
RecruitingNCT05035511Updated Jun 24, 2026

A Machine Learning Approach for Predicting tDCS Treatment Outcomes of Adolescents With Autism Spectrum Disorders

An interventional study of tDCS in Transcranial Direct Current Stimulation, Autistic Disorders Spectrum and Electroencephalography, sponsored by The Hong Kong Polytechnic University. Recruiting at 1 site in Hong Kong. Open to participants aged 12 Years to 22 Years. Per ClinicalTrials.gov, last updated 2026-06-24.

Sponsored by The Hong Kong Polytechnic University · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Started Jan 2022; still recruiting 4 years 10 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
90
Allocation
Not applicable
Ages
12 Years to 22 Years
Sex
All
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Study summary

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by disturbances in communication, poor social skills, and aberrant behaviors. Particularly detrimental are the presence of restricted and repetitive stereotyped behaviors and uncontrollable temper outbursts over trivial changes in the environment, which often cause emotional stress for the children, their families, schools and neighborhood communities.

Fundamental to these cognitive and behavioral problems is the disordered cortical connectivity and resultant executive dysfunction that underpin the use of effective strategies to integrate information across contexts. Brain connectivity problems affect the rate at which information travels across the brain. Slow processing speed relates to a reduced capacity of executive function to recall and formulate thoughts and actions automatically, with the result that autistic children with poor processing speed have great difficulty learning or perceiving relationships across multiple experiences. In consequence, these children compensate for the impaired ability to integrate information from the environment by memorizing visual details or individual rules from each situation. This explains why children with autism tend to follow routines in precise detail and show great distress over seemingly trivial changes in the environment.

To date, there is no known cure for ASD, and the disorder remains a highly disabling condition. Recently, a non-invasive brain stimulation technique, transcranial direct current Stimulation (tDCS) has shown great promise as a potentially effective and costeffective tool for reducing core symptoms such as anxiety, aggression, impulsivity, and inattention in patients with autism. This technique has been shown to modify behavior by inducing changes in cortical excitability and enhancing connectivity between the targeted brain areas. However, not all ASD patients respond to this intervention the same way and predicting the behavioral impact of tDCS in patients with ASD remains a clinical challenge. This proposed study thus aims to address these challenges by determining whether resting-state EEG and clinical data at baseline can be used to differentiate responders from non-responders to tDCS treatment. Findings from the study will provide new guidance for designing intervention programs for individuals with ASD.

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Conditions studied

  • Transcranial Direct Current Stimulation
  • Autistic Disorders Spectrum
  • Electroencephalography
  • Machine Learning
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In context

Child Development Disorders, Pervasive

117 studies on the registry are indexed under Child Development Disorders, Pervasive; 15 are open to participants now.

This study's planned enrollment of 90 is above the median of 45 across 85 interventional studies indexed under Child Development Disorders, Pervasive.

Browse Child Development Disorders, Pervasive studies →

Lead sponsor

The Hong Kong Polytechnic University is the lead sponsor of 679 studies on the registry; 257 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
12 Years to 22 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Individuals who are confirmed by a clinical psychologist based on the -5th Ed (DSM-V) criteria of Autism spectrum disorder and structured interview with their parents or primary caregivers on their developmental history using the Autism Diagnostic Interview-Revised (ADI-R).
  • Individuals with intelligence quotient above 60.
  • Individuals who demonstrate the ability to comprehend testing and stimulation instructions.

Exclusion criteria

Exclusion Criteria:

  • Individuals with severe motor dysfunctions that would hinder their participation, and those with history of other neurological and psychiatric disorders and head trauma, or on psychiatric medication will be excluded from the study
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

DSM diagnostic criteria

The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
90 participants (estimated)

Study arms

  • Experimental
    Responders vs Non-responders

    After the tDCS outcome recorded immediately after tDCS treatment, participants will be categorized into responders and non-responders based on the percentage of change in the total SRS score (primary outcome). Participants that show reductions of at least 10% in the total SRS scores as compared to baseline scores will be considered responders.

    Device: tDCS

Interventions

  • DevicetDCS

    Active-tDCS over 10 sessions in 2 weeks (once per day, for 10 consecutive working days), while performing the executive function training tasks. Also, participants will complete an online cognitive training program while they receive active tDCS stimulation for 10 training sessions. The training session will last for 20 minutes and the online cognitive training program is comprised of 5 exercises targeting at information processing speed and executive function capacities. Each exercise lasts for approximately 4 minutes, totaling approximately 20 minutes.

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What researchers measure

Primary outcomes

  1. Change in behavioral measures (social communication and restricted repetitive behavior) - Social Responsiveness Scale-2nd edition (SRS-2)

    SRS-2 is a sensitive measure of social functioning in children that detects even subtle symptoms that are highly related to ASD. It uses a four-point scale and focuses on different aspects of socialization. The total score reflects the clinical effectiveness of tDCS, and higher scores indicate greater symptom severity. It has been shown that SRS-2 is sensitive to detect changes in social communication improvement related to improved cognitive functioning after treatment. After the tDCS outcome recorded immediately after tDCS treatment, participants will be categorized into responders and non-responders based on the percentage of change in the total SRS score (primary outcome). Participants that show reductions of at least 10% in the total SRS scores as compared to baseline scores will be considered responders.

    Time frame: Day 1 of intervention, and 1 day after the last day of intervention (2 time points)

Secondary outcomes

  1. ASD symptomatology - The Autism Diagnostic Interview-Revised (ADI-R)

    ADI-R is a semi-structured interview conducted with parents, which consists of detailed questions about early developmental and current functioning of the child. It consists of three scales, Social Interaction, Communication, and Repetitive/Stereotyped Behavior. An autism diagnosis is indicated when scores in all three behavioral areas meet the specified minimum cutoff scores, with higher scores indicating more severe autistic features.

    Time frame: Day 1 of intervention (1 time point)

  2. Change in CANTAB® cognitive tests - Multitasking Test (MTT)

    Cambridge Neuropsychological Test Automated Battery (CANTAB®) includes computerized tests correlated to neural networks and have demonstrated high sensitivity in detecting changes in neuropsychological performance. MTT assesses the ability to resolve the interference of task-irrelevant information (stroop-like effect). The test displays an arrow which can appear on either the left or right side of the screen and can point to either the left or right side. In each trial, participants are presented with a cue that indicates which button to press according to two different rules. And the rules that participants have to follow may change from trial to trial in a randomized order. Participant's response latencies and error scores will be measured.

    Time frame: Day 1 of intervention, and 1 day after the last day of intervention (2 time points)

  3. Change in CANTAB® cognitive tests - Stop Signal Task (SST)

    SST assesses a participants' motor inhibition of a prepotent response. The participant is required to respond to an arrow stimulus by selecting one of two options, depending on the direction in which the arrow points. If an audio tone is present, the subject must withhold making the response.

    Time frame: Day 1 of intervention, and 1 day after the last day of intervention (2 time points)

  4. Change in CANTAB® cognitive tests - Emotion Recognition Task (ERT)

    ERT assesses emotional recognition ability of an individual. The participant is required to determine the emotion of the face displayed from 6 options (i.e. sadness, happiness, fear, anger, disgust or surprise) after viewing the facial features of real individuals for 200 milliseconds.

    Time frame: Day 1 of intervention, and 1 day after the last day of intervention (2 time points)

  5. Change in Neurophysiological measures

    EEG resting-state theta coherence (4-7.5 Hz) will be computed from EEG signals collected from the 19 electrode positions (Fp1, Fp2, F3, F4, F7, F8, Fz, T3, T4, T5, T6, C3, C4, Cz, P3, P4, Pz, O1, and O2). Four mean coherence values will be computed, including two intra-hemispheric theta coherence values (intra-left frontoposterior: F7-P3, F7-O1, F3-P3, F3-O1; and intra-right frontoposterior: F8-P4, F8-O2, F4-P4, F4-O2); and two inter-hemispheric theta coherence values (inter-frontal: F3-F4, F7-F8, F3-F8, F4-F7; and inter-frontoposterior: F7-P4, F7-O2, F3-P4, F3-O2, F8-P3, F8-O1, F4-P3 and F4-O1). Each coherence value will then be transformed using Fisher's Z-transformation.

    Time frame: Day 1 of intervention, and 1 day after the last day of intervention (2 time points)

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Study locations

1 of 1 sites recruiting
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References and documents

Publications

  • Chan MMY, Wong KL, Shea CKS, Saxena D, Cheung MC, Chan AS, Han YMY. Baseline symptom severity and response to multisession cathodal transcranial direct current stimulation in adolescents and young adults with autism: an exploratory analysis. J Psychiatr Res. 2026 Jul;198:203-209. doi: 10.1016/j.jpsychires.2026.03.043. Epub 2026 Mar 26. PubMed 41921246 ↗
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Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Jan 2022 (actual). Primary completion is estimated for Dec 2026, 59 months after the start.

Of 29 non-industry interventional studies with no phase under Child Development Disorders, Pervasive, half reached primary completion within 26 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 64. This study's planned 59 months is above that.

Counting every sponsor, half of 30 studies reached it within 26 months; a quarter within 9 and three quarters within 68.

How these figures are worked out, and which studies are left out of them.

Registered
Aug 30, 2021
First posted
Sep 5, 2021
StartActual
Jan 5, 2022
Primary completionEst.
Dec 31, 2026
CompletionEst.
Dec 31, 2026
Last update
Jun 24, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jun 24, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT05035511
Responsible party
Dr Yvonne Han (Associate Professor, The Hong Kong Polytechnic University) — Principal investigator
First posted
Sep 5, 2021
Start date
Jan 5, 2022
Primary completion
Dec 31, 2026 (estimated)
Completion
Dec 31, 2026 (estimated)
Last update
Jun 24, 2026

Study contacts

Yvonne Han, PhD
Contact
yvonne.han@polyu.edu.hk
2766 7578
Yvonne Han, PhD
principal investigator · The Hong Kong Polytechnic University

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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