Targeting Repetitive Behaviors in Autism Spectrum Disorder Via Transcranial Direct Current Stimulation

Bambino Gesù Hospital and Research Institute

Status: Enrolling

Conditions: Autism Spectrum Disorder

Treatments: Device: Active HD-tDCS over pre-SMA; Device: Active HD-tDCS over left DLPFC; Device: Sham HD-tDCS

Study type: Interventional

Funder types: Other

Identifiers

NCT06645587

GR-2021-12375413

Details and patient eligibility

About

Repetitive behaviors (RBs) are a prevalent feature of Autism Spectrum Disorder (ASD). There are two groups of RBs: lower-order (e.g. motor stereotypies) and higher-order RBs (e.g. restricted interests), linked to sensory-motor and the associative loops, respectively. To date, treatment options for RBs are very limited. High-definition transcranial direct current stimulation (HD-tDCS) may be effective in reducing the impact of RBs in children with ASD by targeting the associated brain alterations. Moreover, the high focality of HD-tDCS will help the investigators to disentangle the relative contribution of different brain loops (namely, sensory-motor and the associative loops) into RBs subtypes. The investigators will also study the electrophysiological patterns associated to behavioral changes after the application of HD-tDCS.

Full description

The experimental design will be the following: randomized, three-arm, between subject, double blind, and placebo-controlled.

Children and adolescents with ASD will be selected and randomly assigned to three groups: 1. Active high-definition tDCS (HD-tDCS) over pre-SMA; 2. Active high-definition tDCS (HD-tDCS) left DLPFC; 3. Sham high-definition tDCS (HD-tDCS).

In this project, the investigators will work to understand whether a brain-based intervention, with the use of HD-tDCS can enhance RBs in individuals with ASD.

The protocol will allow the investigators to:

1. Test if Active high-definition tDCS (HD-tDCS) compared to sham HD-tDCS will contribute in reducing RBs
2. Test if HD-tDCS over pre-SMA cortex will decrease lower-order RBs, while HD-tDCS over dlPFC will decrease higher-order RBs
3. Test if the Active Groups will significantly improve in the remaining psychological measures compared to the Sham Group
4. Test if the Active Groups will change in the RBS-R total score will be significantly correlated with changes in neuropsychological and electroencephalographic (EEG) connectivity measures
5. Test if the Active Groups will change in the RBS-R total score will be significantly correlated with changes in the remaining psychological measures and parental stress.

The overarching goal is to provide a scientific foundation for devising new rehabilitation strategies in ASD.

Enrollment: 78 estimated patients

Sex: All

Ages: 8 to 13 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• participants of both genders with ASD diagnosis according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) and based on clinical evaluation and administration of gold standard tools for ASD diagnosis
• an intelligence quotient (IQ) higher or equal to 70 (IQ ≥ 70)
• age range from 8 years to 13 years and 11 months included

Exclusion criteria

• the presence of neurological/medical/genetic conditions (i.e., brain tumours or genetic syndromes)
• personal or family history of epilepsy
• other primary psychiatric diagnoses (i.e., bipolar disorders, schizophrenia spectrum disorders, or adjustment disorder)
• sensorimotor deficits
• the presence of peacemaker or other metal devices in the body;
• ongoing CNS-active drug treatment
• receiving other cognitive-behavioral therapies specifically focused on RBs in the 3 months before the study

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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78 participants in 3 patient groups

Arm Pre-SMA

Active Comparator group

Description:

Active cathodal HD-tDCS over pre-SMA cortex. For HD-tDCS a 4 × 1 montage, small circular electrodes (diameter 1 cm) will be used with the cathode placed centrally over Fz with a current intensity of 0.5 mA for a total of 20 minutes (30 s ramp up/down). For the electrodes' placement, the investigators will follow the recommended guidelines for children.

Treatment:

Device: Active HD-tDCS over pre-SMA

Arm left-dlPFC

Active Comparator group

Description:

Active cathodal HD-tDCS over left dlPFC cortex. For HD-tDCS a 4 × 1 montage, small circular electrodes (diameter 1 cm) will be used with the cathode placed centrally over F3 with a current intensity of 0.5 mA for a total of 20 minutes (30 s ramp up/down). For the electrodes' placement, the investigators will follow the recommended guidelines for children.

Treatment:

Device: Active HD-tDCS over left DLPFC

Arm Sham

Sham Comparator group

Description:

Sham HD-tDCS will be delivered over pre-SMA or left-dlPFC cortex. The same electrodes placement as well as the stimulation set-up will be used as in the active stimulation conditions, but the current will be applied for 30 s and will be ramped down (0 mA) during the rest of the session without the participants awareness.

Treatment:

Device: Sham HD-tDCS