Cumulative and Booster Effects of Multisession Prefrontal Transcranial Direct Current Stimulation in Adolescents with ASD

The Hong Kong Polytechnic University

Status: Enrolling

Conditions: Booster Effects; Electroencephalography; Autistic Spectrum Disorder; Transcranial Direct Current Stimulation

Treatments: Behavioral: Cognitive training; Device: Active-tDCS; Device: Sham-tDCS

Study type: Interventional

Funder types: Other

Identifiers

NCT05492032

HSEARS20220216004-01

Details and patient eligibility

About

Autism spectrum disorder (ASD) is a pervasive and lifelong developmental disorder that currently affects 1 in 54 children. Individuals with autism are often severely impaired in communication, social skills, and cognitive functions. Particularly detrimental characteristics typical of ASD include the inability to relate to people and the display of 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. To date, there is no cure for ASD, and the disorder remains a highly disabling condition. Recently, transcranial direct current stimulation (tDCS), a noninvasive neuromodulation technique, has shown great promise as an effective and cost-effective tool for reducing core symptoms, such as anxiety, aggression, impulsivity, and poor social communication, in patients with autism. Although the empirical findings in patients with ASD are encouraging, it remains to be determined whether these experimental data can be translated into real-world benefits. An important next step is to better understand the factors affecting the long-term efficacy of tDCS treatment - in particular, the possible risk factors associated with relapse in patients with ASD and the role of booster session tDCS as an add-on treatment to induce long-lasting neuroplastic effects in ASD.

Enrollment: 150 estimated patients

Sex: All

Ages: 12 to 21 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Individuals who are confirmed by a clinical psychologist based on the Diagnostic and Statistical Manual of Mental Disorders-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 ASD who are comorbid with ADHD symptoms will be included if they were willing to abstain from the use of these medications at least 96 hours before the commencement, until the completion, of the treatment.
• In view of the fact that neuroadaptation to antipsychotics typically occurs within six months, potential participants who are prescribed antipsychotic medications will only be included if the dosage of the medication remained unchanged for six months or more before the experimental period.

Exclusion criteria

• Individuals without a confirmed diagnosis from the clinical psychologist, with a history of other neurological and psychiatric disorders and head trauma, or on psychiatric medication will be excluded from the study.
• In view of the possibility of seizure induction by tDCS, potential ASD participants comorbid with epilepsy will be excluded.
• Potential participants comorbid with mood or anxiety disorders will also be excluded.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

---

150 participants in 3 patient groups

Active cathodal (inhibitory) tDCS vs. Sham-tDCS condition

Experimental group

Description:

Experimental group: active multisession tDCS + active booster tDCS vs Active control group: sham multisession tDCS + sham booster tDCS To test whether active cathodal \[inhibitory\] tDCS over the left dlPRC will facilitate learning through stimulation and thus improve cognitive function in patients with ASD, the primary outcomes (SRS-2 scores) of the two groups at the start (T0), 1-month (T1), 3-month (T2), 6-month (T3), and at the end of study i.e. 12-months (T4) will be compared.

Treatment:

Device: Sham-tDCS

Device: Active-tDCS

Behavioral: Cognitive training

Active booster tDCS treatment vs. Sham booster tDCS treatment

Experimental group

Description:

Experimental group: active multisession tDCS + active booster tDCS vs Active control group: active multisession tDCS + sham booster tDCS To test whether booster treatment cycles of tDCS will prolong the cognitive benefits in individuals with ASD), the primary outcome, the total SRS-2 score, and the secondary outcomes, the E/I ratio and the cognitive composite score at the start (T0), 1-month (T1), 3-month (T2), 6-month (T3), and at the end of study i.e. 12-months (T4), will be compared.

Treatment:

Device: Sham-tDCS

Device: Active-tDCS

Behavioral: Cognitive training

Change in EEG E/I ratios in the active tDCS vs. sham tDCS groups

Experimental group

Description:

Experimental group: active multisession tDCS + active booster tDCS vs Active control group: sham multisession tDCS + sham booster tDCS To test whether enhanced neuronal network organization, as indicated by EEG E/I ratios, in patients with ASD will mediate the beneficial effects of tDCS in terms of improvements in cognitive function, measurements taken at baseline, 1-day and 1-month after tDCS treatment will be compared. The change in EEG E/I ratios in patients in the active tDCS and sham tDCS groups will be compared using E/I ratios averaged from channels Fp1, F3, and F7 to increase the signal-to-noise ratio of the EEG data and to represent the left frontal E/I ratio.

Treatment:

Device: Sham-tDCS

Device: Active-tDCS

Behavioral: Cognitive training