Stimulating Language in Subacute StrokE "SLISSE"

Recruiting

Phase 1/2 Results N/A

Trial Description

The investigators will study the effects of transcranial direct current (tDCS) stimulation during language therapy for naming in individuals with aphasia in the acute and subacute post stroke period. Naming difficulties are a persistent and common symptom in aphasia after left-hemisphere (LH) stroke. Behavioral therapy (speech and language therapy; SALT) is the mainstay treatment for post stroke aphasia. Transcranial direct cortical stimulation (tDCS) is a promising adjunct to traditional SALT. tDCS is a safe, non-invasive, non-painful electrical stimulation of the brain which modulates cortical excitability by application of weak electrical currents in the form of direct current brain polarization. It is usually administered via saline-soaked surface sponge electrodes attached to the scalp and connected to a direct current stimulator with low intensities. Most studies are conducted in the chronic phase after stroke. Because neuroplasticity is greatest early after stroke, there is reason to believe tDCS might be most effective in the acute-subacute period. However, only two studies have evaluated tDCS paired with language therapy in group studies of acute to subacute aphasic stroke patients and only one of these was sham-controlled. Furthermore, no studies (of which we are aware) have combined tDCS with therapy to facilitate naming in post stroke aphasia, as shown to be effective in studies of chronic stroke. In this study, the investigators will evaluate whether tDCS combined with SALT improves naming in individuals with aphasia in the acute and subacute post stroke period, more than SALT alone in a randomized, double-blind, sham-controlled trial. The investigators will test the hypothesis that anodal tDCS (A-tDCS) over a targeted region and computer-delivered SALT is associated with greater gains in accuracy in naming pictures, compared to sham combined with the same computer-delivered SALT in post stroke aphasia.

Detailed Description

After informed consent is received, a neurological examination will be performed and multiple screening assessments will be conducted including a tDCS and MRI safety screening. If the participant passes the initial screening portion, speech and language diagnostic testing will be conducted during the same visit (Visit 1). During the next visit (Visit 2), participants will undergo a second baseline assessment of naming ability and assessment of connected speech. On that visit, participants who have no contraindication for MRI (and agree to have MRI) will be randomized to (1) fMRI electrode placement or (2) structural electrode placement. All participants who have no contraindication will have structural and resting state functional connectivity MRI (rsfcMRI). Those randomized to fMRI electrode placement will also participate in the naming paradigm during the MRI. The third visit will include electrode positioning and tDCS treatment administration. Participants will receive 15 sessions (Visits 3-17) of tDCS + SALT administration. At the beginning of Visit 3, eligible participants will be randomized to receive either A-tDCS (1 mA) or sham-tDCS (placebo) for 15 sessions (20-minutes per each 45-minute behavioral treatment session) over the course of three weeks. A computer-delivered naming treatment will be coupled with the stimulation. The computer-delivered treatment task will be 45-minutes in total length, so that it will commence at the same time as the tDCS administration and continue for another 25-minutes after the tDCS has ceased. To assess cardiovascular arousal, blood pressure and heart rate will be measured before and after each session. Additionally, discomfort ratings will be recorded following the end of each session using the Wong-Baker FACES Pain Rating Scale and a weekly neurological exam will be administered by a neurologist. Neither the participant nor the clinician monitoring and setting up the treatment will have knowledge of the treatment condition (A-tDCS versus sham). Utilizing a computerized picture naming assessment, all participants will be assessed at several different time points throughout the experiment: twice immediately before and twice the week immediately following the fifteenth and final treatment session; twice at five weeks follow-up after the end of treatment; and twice at 20 weeks after the end of treatment. Participants who agree to participate in the MRI portion of the study (and have none of the additional exclusion criteria for MRI) will have structural and rsfcMRI at Visit 2, following the 15th treatment session (Week 1 after the end of treatment), and at 5 weeks after the end of treatment.

Conditions

Interventions

  • Sham Device
    Intervention Desc: 1 mA of A-tDCS stimulation is induced between two 5 cm x 5 cm saline soaked sponges where one sponge (anode: A-tDCS) is placed on the scalp over the targeted cortical region. Ramping up of the current to 1 mA occurs over 10-15 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.
    ARM 1: Kind: Experimental
    Label: Sham-tDCS & SALT
    Description: Sham-tDCS plus SALT for 15 sessions (20-minutes per each 45-minute treatment session) over the course of 3 weeks. Current will be administered in a ramp-like fashion, but after the ramping, the intensity will drop to 0 mA. SALT will be a computer delivered oral naming + picture naming task.
  • A-tDCS (1 mA) Device
    Other Names: Anodal transcranial direct current stimulation
    Intervention Desc: 1 mA of A-tDCS stimulation is induced between two 5 cm x 5 cm saline soaked sponges where one sponge (anode: A-tDCS) is placed on the scalp over the targeted cortical region. Ramping up of the current to 1 mA occurs over 10-15 seconds to allow participants to habituate to the tingling sensation. A-tDCS stimulation will be active only in the first 20 minutes of the 45-minute treatment session.
    ARM 1: Kind: Experimental
    Label: A-tDCS & SALT
    Description: A-tDCS (1 mA) plus Speech and Language Treatment (SALT) for 15 sessions (20-minutes per each 45-minute treatment session) over the course of 3 weeks. The electrical current will be administered to a pre-specified region of the brain. The stimulation will be delivered at an intensity of 1mA for a maximum of 20 minutes. SALT will be a computer-delivered naming + picture matching task .
  • SALT Behavioral
    Other Names: Speech and Language Treatment
    Intervention Desc: Computer-delivered naming treatment requires matching word (heard and seen being produced by the speaker) with pictures depicting common objects. It is run on a laptop computer with headphones and 2 large response buttons. During treatment, a picture appears on the laptop screen for 2 seconds. Then, a video of the speaker's face below the nose is presented on the screen saying a word that either matches or does not match the picture. The participant is instructed to press a green response button if the word matches the picture and press the red response button if the word does not match the picture.
    ARM 1: Kind: Experimental
    Label: A-tDCS & SALT
    Description: A-tDCS (1 mA) plus Speech and Language Treatment (SALT) for 15 sessions (20-minutes per each 45-minute treatment session) over the course of 3 weeks. The electrical current will be administered to a pre-specified region of the brain. The stimulation will be delivered at an intensity of 1mA for a maximum of 20 minutes. SALT will be a computer-delivered naming + picture matching task .
    ARM 2: Kind: Experimental
    Label: Sham-tDCS & SALT
    Description: Sham-tDCS plus SALT for 15 sessions (20-minutes per each 45-minute treatment session) over the course of 3 weeks. Current will be administered in a ramp-like fashion, but after the ramping, the intensity will drop to 0 mA. SALT will be a computer delivered oral naming + picture naming task.

Trial Design

  • Allocation: Randomized
  • Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
  • Purpose: Treatment
  • Endpoint: Efficacy Study
  • Intervention: Parallel Assignment

Outcomes

Type Measure Time Frame Safety Issue
Primary Change in accuracy of naming untrained pictures (Philadelphia Naming Test) pre- to post-treatment Change is averaged over 2 sessions (to reduce variability) on 2 consecutive days immediately before treatment and 2 consecutive days within 1 week after the end of treatment. No
Secondary Change in accuracy of naming untrained pictures (Philadelphia Naming Test) pre- -treatment to 5-weeks and 20-weeks post-treatment The PNT will be administered at baseline and at 5 and 20 weeks post treatment. No
Secondary Change in content of picture description pre- to post-treatment Immediately before and within 1 week after treatment No
Secondary Change in efficiency of picture description pre- to post-treatment Immediately before and within 1 week after treatment No
Secondary Change in content of picture description pre-treatment to 5 weeks and 20-weeks post-treatment Immediately before and at 5 weeks and 20 weeks after treatment No
Secondary Change in efficiency of picture description pre-treatment to 5 weeks and 20-weeks post-treatment Immediately before and at 5 weeks and 20 weeks after treatment No
Secondary Change in Stroke Impact Scale (SIS) pre-treatment to post-treatment Immediately before and within 1 week after treatment No
Secondary Change in Stroke Impact Scale (SIS) pre-treatment to 5 weeks and 20 weeks post-treatment Immediately before and 5 and 20 weeks after treatment No

Sponsors