taVNS for Letter Learning in Dyslexia

Not Applicable

Not yet recruiting

• Conditions: Dyslexia
• Interventions: Device: sham taVNS; Device: active taVNS

• Registration Number: NCT06127550
• Lead Sponsor: University of Florida

Brief Summary

This is a pilot study to establish feasibility of transcutaneous auricular vagus nerve stimulation (taVNS) for improving letter-learning in adolescents with dyslexia. The main goals of the study are to 1) evaluate whether children in this age range will tolerate low level stimulation over the course of multiple sessions, 2) determine whether low level taVNS improves novel letter learning in dyslexia, and 3) evaluate the effect of low level taVNS on the brain's response to letters. Participants will complete fMRI before training, immediately after training, and a few weeks after training ends. Training will consist of six 30-minute lessons during which participants will learn novel letter-sound relationships while receiving either active or sham taVNS. Researchers will compare stimulation conditions to determine effect of this device on learning and neural plasticity.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2023-10-27
• Study First Submitted QC: 2023-11-07
• Study First Posted: 2023-11-13
• Status Verified: 2025-02
• Last Update Submitted: 2025-02-10
• Last Update Posted: 2025-02-11
• Study Start: 2025-09-01
• Primary Completion: 2028-08-01
• Study Completion: 2029-09-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

• Normal non-verbal IQ
• Reading scores above 90 on four single word reading measures (typical reader) OR reading scores below 90 on two or more single word reading measures (dyslexia) with or without ADHD

Exclusion Criteria

• Neurological diagnoses (e.g., autism, epilepsy, etc.)
• Medications other than those prescribed for ADHD
• Nonverbal IQ below 80

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Sham taVNS	sham taVNS	Participants will undergo current thresholding but device will be turned off without their knowledge during the training.
Active taVNS	active taVNS	Participants will receive custom current at 5 Hz to the left auricular branch of the vagus nerve while learning new letter-sound relationships.

Primary Outcome Measures

Name	Time	Method
Adverse events	4 weeks	Frequency and severity of adverse events will be monitored and evaluated for severity and impact on attrition.
Compliance	4 weeks	Percentage of the population that remains engaged in the study and completes all stimulation sessions.

Secondary Outcome Measures

Name	Time	Method
Letter ID	6 weeks	Percent correct of learned letter-sound relationships
Decoding	6 weeks	Percent correct of pseudowords read in 45 seconds
Automaticity	6 weeks	This measure is based on a standardized measure for rapid letter naming in English (CTOPP-Rapid Automatized Naming) in which the participant is shown a grid of many letters in Hebrew and are asked to read the grid as quickly and accurately as possible while being timed.

Trial Locations

Locations (1)

University of Florida; 🇺🇸 Gainesville, Florida, United States