Brain Stimulation With Combined Reading and Motor Training for Children With Dyslexia

August 21, 2026 updated by: Mohammad Amin Javedanfar, Shahid Beheshti University

Effectiveness of Dual-Site tDCS Combined With Integrated Phonological and Fine Motor Intervention in 9-Year-Old Boys With Developmental Dyslexia: A Randomized, Double-Blind, Sham-Controlled Trial

This study examines whether combining non-invasive brain stimulation (tDCS) with an integrated reading-and-motor training program improves reading and phonological processing in 9-year-old boys with developmental dyslexia.

Children with dyslexia often have difficulties in phonological awareness and fine motor skills. This study targets two brain areas at the same time: the left temporoparietal junction (important for reading and phonological processing) and the left primary motor cortex (important for hand movements and speech-related motor processes).

Participants will be randomly assigned to one of eight groups. Some groups will receive active brain stimulation, and some will receive sham (inactive) stimulation, while also participating in different types of training: phonological awareness training, fine motor training, combined phonological and fine motor training, or no training. The treatment includes 20 sessions, three times per week for about 7 weeks.

Reading and phonological skills will be measured before treatment, immediately after treatment, and again 3 months and 6 months later. The study will help determine whether a full treatment package-using brain stimulation together with combined reading and motor training-is more effective than single treatments or usual school education.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

This is a randomized, double-blind, sham-controlled, 8-group component trial in 9-year-old boys with developmental dyslexia. The study tests a theory-driven prediction derived from multiple-deficit models of dyslexia: that simultaneously targeting reading-related and sensory-motor brain networks, while delivering an integrated phonological and fine motor intervention, produces greater and more durable reading improvement than single-component interventions.

The tDCS protocol uses 1 mA current for 20 minutes per session over 20 sessions (3 sessions/week). Electrode montages are yoked to the type of cognitive intervention: left temporoparietal (TPJ) for phonological training, left primary motor cortex (M1) for motor training, and dual-site TPJ+M1 for the combined intervention. A tDCS-only group (M1 montage) is included to isolate the effect of motor cortex stimulation.

Primary outcome: change in the composite score of Factor 1 of the Reading and Dyslexia Test (word reading, phoneme deletion, nonword reading, and word comprehension). Secondary outcomes: fine motor performance (BOT-2), rapid automatized naming, and text reading fluency.

Assessments occur at baseline, immediately after the intervention, and at 3- and 6-month follow-ups.

Study Type

Interventional

Enrollment (Estimated)

160

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Isfahan
      • Isfahan, Isfahan, Iran, 8155113853
        • Consultation, Psychological, Research and Specialized Services Center of Isfahan Province General Department of Education
        • Contact:
        • Sub-Investigator:
          • Mohammad Amin Javedanfar, MSc

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Male children aged 9 years (9 years 0 months to 9 years 11 months) with developmental dyslexia diagnosed according to DSM-5 criteria by a clinical team.
  • Reading and Dyslexia Test (NAMA) T score ≤ 30 (at least 2 standard deviations below the mean).
  • Full Scale IQ ≥ 85 on the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V).
  • Score below 88 on the Spence Children's Anxiety Scale (SCAS).
  • Fine motor deficits defined as standard score ≤ 40 on Bruininks-Oseretsky Test of Motor Proficiency, Second Edition (BOT-2) manual dexterity and upper-limb coordination subtests.
  • Normal or corrected-to-normal vision and hearing.
  • No history of seizure or epilepsy, no scalp skin disease, no cochlear implant, cardiac pacemaker, or metal implants in the skull.
  • Written informed consent from parents or legal guardian and verbal assent from the child.

Exclusion Criteria:

  • Intellectual disability (Full Scale IQ < 85).
  • Personal history of epilepsy or seizure disorder, or epilepsy in a first-degree relative.
  • Presence of cochlear implant, cardiac pacemaker, or metal implants in the skull.
  • Skin diseases or open lesions on the scalp at electrode sites.
  • Uncorrected visual or hearing impairments.
  • Other primary psychiatric or neurodevelopmental disorders requiring ongoing treatment (e.g., ADHD, autism spectrum disorder, severe anxiety disorder).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Sham Comparator: Control (Sham + Usual School)
Sham tDCS randomly selected montage + usual school education, no cognitive training
Sham tDCS will use the same electrode positions as the active groups, but the current will be applied for only 30 seconds and then gradually ramped down.
Other Names:
  • Sham tDCS
Participants receive the standard school curriculum without additional cognitive or motor training.
Sham Comparator: Sham-PA
Sham tDCS TPJ + phonological awareness training
Sham tDCS will use the same electrode positions as the active groups, but the current will be applied for only 30 seconds and then gradually ramped down.
Other Names:
  • Sham tDCS
20 sessions of 60 minutes each, three times per week for about 7 weeks. Covers syllable segmentation, rhyme, phoneme blending and segmentation, initial and final phoneme identification, phoneme manipulation, and grapheme-to-phoneme mapping.
Other Names:
  • PA training
Sham Comparator: Sham-Motor
Sham tDCS M1 + non-targeted fine motor training
Sham tDCS will use the same electrode positions as the active groups, but the current will be applied for only 30 seconds and then gradually ramped down.
Other Names:
  • Sham tDCS
20 sessions of 60 minutes each, three times per week for about 7 weeks. Includes activities without linguistic content, such as free play with dough, bead threading, pegboard tasks, and other manual dexterity exercises.
Other Names:
  • Fine motor training
Sham Comparator: Sham-Comb
Sham dual-channel TPJ+M1 + combined phonological and fine motor intervention
Sham tDCS will use the same electrode positions as the active groups, but the current will be applied for only 30 seconds and then gradually ramped down.
Other Names:
  • Sham tDCS
20 sessions of 60 minutes each, three times per week for about 7 weeks. Combines phonological awareness training with targeted fine motor activities linked to reading, such as forming letters with dough and stringing beads marked with phonemes.
Other Names:
  • Combined intervention
Experimental: Active-PA
Active tDCS TPJ + phonological awareness training
20 sessions of 60 minutes each, three times per week for about 7 weeks. Covers syllable segmentation, rhyme, phoneme blending and segmentation, initial and final phoneme identification, phoneme manipulation, and grapheme-to-phoneme mapping.
Other Names:
  • PA training
Active tDCS will be delivered at 1 milliampere for 20 minutes per session, 20 sessions over about 7 weeks. The montage varies by arm: left temporoparietal (TPJ) montage, left primary motor cortex (M1) montage, or dual-site TPJ+M1 montage.
Other Names:
  • tDCS
Experimental: Active-Motor
Active tDCS M1 + non-targeted fine motor training
20 sessions of 60 minutes each, three times per week for about 7 weeks. Includes activities without linguistic content, such as free play with dough, bead threading, pegboard tasks, and other manual dexterity exercises.
Other Names:
  • Fine motor training
Active tDCS will be delivered at 1 milliampere for 20 minutes per session, 20 sessions over about 7 weeks. The montage varies by arm: left temporoparietal (TPJ) montage, left primary motor cortex (M1) montage, or dual-site TPJ+M1 montage.
Other Names:
  • tDCS
Experimental: Active-Comb
Active dual-site TPJ+M1 + combined phonological and fine motor intervention
20 sessions of 60 minutes each, three times per week for about 7 weeks. Combines phonological awareness training with targeted fine motor activities linked to reading, such as forming letters with dough and stringing beads marked with phonemes.
Other Names:
  • Combined intervention
Active tDCS will be delivered at 1 milliampere for 20 minutes per session, 20 sessions over about 7 weeks. The montage varies by arm: left temporoparietal (TPJ) montage, left primary motor cortex (M1) montage, or dual-site TPJ+M1 montage.
Other Names:
  • tDCS
Experimental: Active-Only
Active tDCS M1 alone, no cognitive intervention
Active tDCS will be delivered at 1 milliampere for 20 minutes per session, 20 sessions over about 7 weeks. The montage varies by arm: left temporoparietal (TPJ) montage, left primary motor cortex (M1) montage, or dual-site TPJ+M1 montage.
Other Names:
  • tDCS

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Composite score of Factor 1 of the Reading and Dyslexia Test (NAMA)
Time Frame: Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.
Composite score of Factor 1 of the Reading and Dyslexia Test, which includes word reading, phoneme deletion, nonword reading, and word comprehension subtests.
Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Fine motor performance (BOT-2 manual dexterity and upper-limb coordination)
Time Frame: Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.
Fine motor performance as measured by the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition, manual dexterity and upper-limb coordination subtests. Raw scores of the common items will be used for longitudinal comparison.
Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.
Rapid automatized naming speed
Time Frame: Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.
Rapid automatized naming speed, including naming of objects, colors, numbers, and letters. The total time in seconds to name each card is recorded.
Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.
Text reading fluency (correct words per minute)
Time Frame: Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.
Text reading fluency defined as the number of correct words read per minute on a grade-level reading passage. Correct words per minute will be calculated as the total number of words minus errors, multiplied by 60, divided by the total reading time in seconds.
Before intervention, immediately after the end of intervention, 3 months after intervention, and 6 months after intervention.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Study Chair: Shahriar Gharibzadeh, Ph.D., Institute for Cognitive and Brain Sciences, Shahid Beheshti University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

August 23, 2026

Primary Completion (Estimated)

July 6, 2027

Study Completion (Estimated)

August 1, 2027

Study Registration Dates

First Submitted

August 20, 2026

First Submitted That Met QC Criteria

August 20, 2026

First Posted (Actual)

August 24, 2026

Study Record Updates

Last Update Posted (Actual)

August 25, 2026

Last Update Submitted That Met QC Criteria

August 21, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • SBU-tDCS-Dyslexia-001
  • IRCT20260817070696N1 (Registry Identifier: Iranian Registry of Clinical Trials)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared due to confidentiality and ethical considerations related to minor participants. Sharing of participant-level data was not included in the informed consent or the study ethics approval. Only aggregate, deidentified results will be reported.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

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