tDCS in Adults With ASD and/or ADHD Without Intellectual Disability

Hospital Universitari Vall d'Hebron Research Institute25 enrolled

Overview

The goal of this clinical trial is to learn about the safety and tolerability of transcranial direct current stimulation (tDCS) combined with cognitive training in adults with Autism Spectrum Disorder (ASD) and/or Attention-Deficit/Hyperactivity Disorder (ADHD). The main question it aims to answer is: Is tDCS safe and well-tolerated in adults with ASD and/or ADHD? Researchers will compare active tDCS to a sham (placebo-like) stimulation to evaluate safety and tolerability. Participants will: Receive either active or sham tDCS for 20 minutes daily over 10 consecutive workdays Undergo stimulation with the anode placed at F3 and the cathode at Fp2 Complete daily cognitive training exercises using the NeuronUP platform during stimulation Attend baseline and follow-up assessments to monitor for any side effects or discomfort related to the intervention

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Enrollment

Conditions

Autism Spectrum Disorder Attention Deficit Disorder With Hyperactivity

Interventions

Transcranial Direct Current Stimulation - ActiveDEVICE

This intervention involves non-invasive brain stimulation using transcranial direct current stimulation (tDCS) delivered via saline-soaked sponge electrodes. The anode is placed at F3 (left dorsolateral prefrontal cortex) and the cathode at Fp2 (right frontopolar cortex), according to the international 10-20 EEG system. A 2 mA current is applied for 20 minutes per session, administered once daily on 10 consecutive workdays. During stimulation, participants engage in cognitive training using the NeuronUP platform, which provides structured, interactive tasks designed to train executive function, attention, and working memory. This combination aims to enhance neural plasticity by pairing neuromodulation with cognitive engagement.

Transcranial Direct Current Stimulation - ShamDEVICE

The sham condition mimics the active setup but delivers only brief ramp-up/down stimulation, producing the initial sensation without sustained current.

Cognitive TrainingBEHAVIORAL

The cognitive training intervention in this study is delivered through NeuronUP, a digital platform offering evidence-based cognitive stimulation activities. This intervention targets core cognitive domains such as working memory, attention, and executive function through personalized, interactive tasks. What distinguishes this approach is NeuronUP's extensive library of over 10,000 activities, its ability to tailor difficulty levels in real time based on individual performance, and the inclusion of functional tasks that mirror real-life scenarios. Unlike other interventions, NeuronUP also enables therapist-guided customization, allowing for individualized treatment plans that evolve with participant progress, ensuring both relevance and ecological validity.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: Adults aged 18 to 55 years Clinical diagnosis of Autism Spectrum Disorder (ASD) and/or Attention-Deficit/Hyperactivity Disorder (ADHD) confirmed via medical records or structured clinical interview Able to provide informed consent Fluent in the language used for assessments and cognitive training tasks Stable medication regimen (if applicable) for at least 4 weeks prior to enrollment Willing and able to attend 10 consecutive weekday sessions and follow-up assessment Exclusion Criteria: History of epilepsy, seizures, or significant neurological disorder (e.g., traumatic brain injury, stroke) Current diagnosis of psychotic disorder or bipolar disorder Presence of metal implants in the head (excluding dental work), pacemaker, or other contraindications to tDCS Current substance use disorder (within past 6 months) Pregnant or planning to become pregnant during the study period Participation in another intervention study within the last 30 days Any condition that, in the opinion of the investigators, may make participation unsafe or interfere with study procedures

Outcomes

Primary Outcomes

Incidence of Treatment-Emergent Adverse Events [Safety and Tolerability]

Participants will be monitored for adverse events, side effects (e.g., headache, skin irritation, fatigue), and dropout rates. This will be assessed through participant self-report, clinician observation, and standardized side effect checklists administered during and after each session. The outcome will help determine whether daily tDCS paired with cognitive training is safe and acceptable for adults with ASD and/or ADHD.

Time frame: Throughout the 10-day intervention period and at follow-up (up to 2 weeks post-intervention)