Transcutaneous Vagus Nerve Stimulation in Aphasia After Stroke

Summary

Aphasia is an acquired language disorder. Stroke is the most common cause of aphasia, which affects 30% of stroke survivors. Speech and Language Therapy (SLT) can help people with aphasia but it may not be provided at the required intensity. Access to therapy is often limited after the first few months following stroke. People with aphasia can improve with therapy many years after stroke but these benefits have not been found to translate to day to day conversation.

Transcutaneous Vagus Nerve Stimulation (tVNS) is a non-invasive technique which involves stimulating a branch of the vagus nerve through the skin of the ear, using a small earpiece. This technique is safe and has been approved for use in headache. There is promising evidence that tVNS can improve motor rehabilitation in chronic stroke. This technique may be helpful in aiding language recovery in individuals with chronic aphasia.

The current pilot study will primarily assess the feasibility, safety and tolerability of self-directed tVNS paired with computer-based SLT, in individuals with chronic stroke-related aphasia. Secondly, the study aims to explore the effect of the intervention on word-finding ability and to explore potential mechanisms of action. Participants will be randomly allocated to an active or sham tVNS group. Participants will be asked to use the stimulation device at home for 6 weeks, whilst completing computer-based SLT. To date, there are no published studies exploring the use of tVNS in aphasia. An indication of study feasibility may support the development of a larger RCT to explore treatment efficacy.

Conditions

• Aphasia
• Chronic Stroke

Interventions

DEVICE

Transcutaneous Vagus Nerve Stimulation

Transcutaneous auricular vagus nerve stimulation using the Nurosym (Parasym Ltd) device. Stimulation parameters: Pulse width: 250µs; Frequency: 25Hz; Intensity: Below pain threshold. The active stimulation will be delivered to the left ear. Participants will complete the intervention at home once they have received sufficient training on how to use the stimulation device.

DEVICE

Sham Transcutaneous Vagus Nerve Stimulation

Stimulation will be delivered at the same parameters however, sham stimulation will be delivered to the left ear. This sham method has been used as a sham in other studies as it is not thought to activate the vagus nerve.

BEHAVIORAL

Computer Based Speech and Language Therapy (Step by Step)

Computer-based Speech and Language Therapy will be completed whilst wearing the stimulation device in all groups. The Step by Step programme uses an errorless learning approach to practice naming. All participants will practice a set of 30 meaningful words during the intervention. Participants will complete the SLT programme at home on an ipad, whilst using the stimulation device.

Sponsors & Collaborators

• Sheffield Teaching Hospitals NHS Foundation Trust

  lead OTHER

Principal Investigators

• Dr Ali Ali · Sheffield Teaching Hospitals NHS Foundation Trust

• Prof. Arshad Majid · University of Sheffield

• Prof. Rebecca Palmer · University of Sheffield

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-04-25

Primary Completion

2026-06-03

Completion

2027-01-01

Countries

• United Kingdom

Study Locations