Recruiting

Cerebellar Stimulation

Sponsor:

Johns Hopkins University

Code:

NCT05093673

Conditions

Stroke

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

Interventions

Cathodal Cerebellar tDCS

Semantic Feature Analysis (SFA)

Sham

Study Details

Brief summary:

The optimal site of neuromodulation for post-stroke aphasia has yet to be established. This study will investigate whether multiple sessions of cerebellar transcranial direct current stimulation (tDCS) boosts language therapy in helping people recover from aphasia as well as predict who is likely to respond to cerebellar tDCS.

Conditions

Stroke

Study ID

NCT05093673

Start date

Oct 25, 2021

Status verified date

Mar, 2026

Completion date

Apr 1, 2028

Anticipated

Primary completion date

Sep 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Chronic ischemic or hemorrhagic left hemisphere stroke
  • Fluent speaker of English by self-report
  • Age 18 or older
  • 6 months post onset of stroke
  • Diagnosis of aphasia and naming impairment using the Western Aphasia Battery-Revised

Exclusion Criteria:

  • Lesion in the right cerebellum
  • Previous neurological disorder (other than stroke) affecting the brain, or any other neurodegenerative disorder or psychiatric disorder
  • Seizures during the previous 6 months
  • Uncorrected visual loss or hearing loss by self-report
  • Use of medications that lower the seizure threshold (e.g., methylphenidate)
  • Use of N-methyl-D-aspartate (NMDA) antagonists (e.g., memantine)
  • History of brain surgery or any metal in the head
  • Severely impaired auditory comprehension (lower than 2 on the Comprehension subscore on the Western Aphasia Battery-Revised)
  • Severely limited verbal output (lower than 2 on the Spontaneous Speech rating scale on the Western Aphasia Battery-Revised)
  • Individuals with severe claustrophobia, cardiac pacemakers or ferromagnetic implants, and pregnant women will be excluded from the MRI portion of the study.

Study Design

Enrollment

60 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

active comparator: Cathodal Cerebellar tDCS and SFA

Cathodal cerebellar tDCS, 2 milliamp (mA) plus Semantic Feature Analysis (SFA) naming treatment for 15 sessions (25-minutes per each 60-minute treatment session) over the course of 3-5 weeks. The electrical current will be administered to the right cerebellum. The stimulation will be delivered at an intensity of 2 mA for a maximum of 25 minutes. SFA will be delivered by a Speech and Language Pathologist to improve naming

sham comparator: Sham Cerebellar tDCS and SFA

Sham cerebellar tDCS plus SFA for 15 sessions (25-minutes per each 60-minute treatment session) over the course of 3-5 weeks. Current will be administered in a ramp-like fashion, but after the ramping, the intensity will drop to 0 mA. SFA will be delivered by a Speech and Language Pathologist to improve naming.

Interventions

Cathodal Cerebellar tDCS

2 mA of cathodal tDCS is induced between two 5cm X 5cm saline soaked sponges where the cathode sponge is placed on the right cerebellum. Ramping up of the current to 2 mA occurs over 15-30 seconds to allow participants to habituate to the tingling sensation. The stimulation will be delivered at an intensity of 2 mA for a maximum of 25 minutes.

Semantic Feature Analysis (SFA)

Semantic Feature Analysis (SFA) is a treatment technique designed to improve lexical retrieval by increasing the level of activation within a semantic network. The treatment will proceed according to a series of steps including naming aloud the target picture, generating semantic features, naming aloud the target picture again, and generating a sentence using the target word.

Sham

2 mA of cathodal tDCS is induced between two 5cm X 5cm saline soaked sponges where the cathode sponge is placed on the right cerebellum. Ramping up of the current to 2 mA occurs over 15-30 seconds to allow participants to habituate to the tingling sensation. Then, the current will be ramped back down to 0 mA in the sham condition. Termination of the stimulation after the ramping up process is generally undetectable, and the brief duration of stimulation yields no functional effects.

Primary outcome measure

  • Change in accuracy of naming untrained pictures (Philadelphia Naming Test) [ Time Frame: Pre-treatment to one week after the end of SFA treatment ]

Central Contacts and Locations

Central contacts

Rajani Sebastian, PhD

410-502-2445rsebast3@jhmi.edu

Becky Lammers, MS

410-502-2445blammer2@jh.edu

Locations

Johns Hopkins Hospital

Recruiting

Baltimore, Maryland, United States, 21287

Contacts

Rajani Sebastian, PhD

410-502-2445rsebast3@jhmi.edu

Becky Lammers, MS

410-502-2445blammer2@jh.edu

More Information

Sponsor

Johns Hopkins University

Last update posted

Mar 20, 2026

Last verified

Mar, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Johns Hopkins University on 2026-03-20.