Table 1.
Summary of non-invasive brain stimulation intervention studies for post-stroke aphasia.
| Study | N | Stroke onset | Methods | FU | Site | Tests | Findings—significant improvement in: |
|---|---|---|---|---|---|---|---|
| rTMS: CASE REPORTS/SERIES | |||||||
| Naeser et al., 2010 | 1 | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day Optimal site finding CPAP | 3, 6, 2.4 years | Right PTr (5 sites: Motor mouth area, and 4 subregions within Broca's area) | Picture naming, BDAE, BNT | Phrase length, auditory comprehension and BNT at 3 and 6 months post-TMS |
| Cotelli et al., 2011 | 3 | Chronic | 20 Hz rTMS 90% RMT 10 or 20 days 25 min/day 25 min of SLT | About 1, 3, 6, 11 | Left dlPFC | AAT, BADA, picture naming, verbal fluency and reasoning | Picture naming accuracy; persistent benefit present 48 weeks after treatment |
| Hamilton et al., 2010 | 1 | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day Optimal site finding | 2, 6, 10 | Right PTr (sites: POp, dpPTr, vpPTr, aPTr, PO, Motor mouth area) | WAB, BDAE-Cookie theft, picture naming | Naming and spontaneous speech; improvement in picture description sustained at 2, 6 and 10 months |
| Barwood et al., 2012 | 7 | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day | 2, 8 | Right PTr | BNT, BDAE, picture naming | Naming accuracy and latency, generalized speech output, and auditory speech comprehension; effects sustained up to 8 months |
| Martin et al., 2009 | 2 | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day Optimal site finding fMRI: changes in activation patterns | 2, 6, 16, 43 | Right PTr (4 sites: POp, aPTr, pPTr, Motor mouth area) | BNT, BDAE—Cookie theft, picture naming | Picture naming and phrase length in one patient (responder; best response site right pPTr); No improvement in the other patient (non-responder; best response site right aPTR) |
| rTMS: GROUP STUDIES | |||||||
| Naeser et al., 2005 | 4 | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day | 2, 8 | Right PTr | BNT, BDAE, picture naming | Picture naming at both 2 and 8 months in 3 patients |
| Kakuda et al., 2011 | 4 | Chronic | 10 min of 6 Hz followed by 20 min of 1 Hz rTMS 90% RMT 11 days 2 sessions/day (except on 1st and last day) 60 min of SLT | − | Right IFG (F8)* | SLTA, J-WAB | (greatest) repetition and naming; 4 patients showed improvement in different categories including naming, repetition, writing, auditory and visual comprehension and speech; none showed deterioration |
| Barwood et al., 2011a | 6 real 6 sham | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day | 2 | Right PTr | BNT, BDAE, picture naming | Naming, aspects of expressive language and auditory comprehension |
| Medina et al., 2012 | 5 real 5 sham (crossed-over to real after 2 months) | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day Cross-over Optimal site finding | 2 | Right IFG (sites: POp, dpPTr, vpPTr, aPTr, PO, Motor mouth area) | BDAE, BNT, narrative speech production | Fluency at 2 months after rTMS, specifically in discourse productivity; no benefit in sentence complexity, grammatical accuracy or lexical selection; for 9/10 patients, the optimal site was right PTr |
| Kindler et al., 2012 | 18 | Sub-acute and Chronic | cTBS (3 pulses at 30 Hz) 2 days—Sham/real Cross-over 44 s/day | − | Right PTr | Timed picture naming, alertness task | Naming and reaction time after TBS vs. sham; no differences observed in arousal; patients in sub-acute phase were best responders |
| Waldowski et al., 2012 | 13 real 13 sham | Sub-acute | 1 Hz rTMS 90% RMT 15 days 30 min/day 45 min SLT | 3.5 | Right PTr and right POp | ASRS, BDAE, picture naming7 | Aphasia severity (ASRS) in real group compared to the sham 15-weeks after treatment; naming accuracy did not differ between groups but reaction time was slightly faster in the real group after treatment; real subgroup with lesions involving frontal area showed slower reaction times |
| Barwood et al., 2013 | 6 real 6 sham | 1 Hz rTMS 90% RMT 10 days 20 min/day | 2, 8, 12 | Right PTr | Naming, expressive language and auditory comprehension up to 12 months in the real group compared to sham | ||
| Barwood et al., 2011b | 6 real 6 sham | Chronic | 1 Hz rTMS 90% RMT 10 days 20 min/day N400 ERP | 2 | Right PTr | BNT, BDAE, picture naming, SJT | (Differences in) mean and peak amplitudes and area under the curve measures of N400 ERP component between real and sham group at 2 months |
| Weiduschat et al., 2011 | 6 real 4 ctrls | Sub-acute | 1 Hz rTMS 90% RMT 8–10 days 20 min/day PET SLT | − | Right PTr or Vertex | AAT | AAT; activation shift toward right hemisphere in control group, absent in intervention group; laterality shift and clinical improvement were not related |
| Szaflarski et al., 2011b | 8 | Chronic | fMRI-guided iTBS (3 pulses at 50 Hz) 10 days 200 s/day 80% AMT LI | − | Left PTr | BNT, SFT, COWAT, PPVT, CAL, BDAE CompId | SFT; activation shifts to the affected left hemisphere; self-reports of improved communicative ability (tendency) |
| Allendorfer et al., 2012b | 8 | Chronic | fMRI-guided iTBS (3 pulses at 50 Hz) 10 days 200 s/day 80% AMT DTI—FA | − | Left PTr | BNT, SFT, COWAT, PPVT, CAL, BDAE CompId | SFT; higher DTI-FA values in the left fronto-temporo-parietal areas |
| Abo et al., 2012 | 24 | Chronic | fMRI (right or left) and aphasia type (STG or IFG)-guided 1 Hz rTMS 90% RMT 10 days 40 min/day 60 min of SLT | − | Fluent: Right STG (CP6*; n = 5), Left STG (CP5; n = 5); Non-fluent: Right IFG (F8; n = 11)Left IFG (F7; n = 3) | SLTA, J-WAB | Auditory and reading comprehension, and repetition in non-fluent aphasia patients; improvement in spontaneous speech in fluent aphasia patients |
| Thiel et al., 2013 | 13 real 11 sham | Sub-acute | 1 Hz rTMS 90% RMT 10 days 20 min/day PET 45 min of SLT | − | Right PTr or Vertex | AAT | Global AAT and naming subtests; larger activation index in the left hemisphere in rTMS group post-treatment compared to the sham group |
| tDCS: GROUP STUDIES | |||||||
| Monti et al., 2008 | 4 a-tDCS 4 c-tDCS | Chronic | a-tDCS and c-tDCS 2 mA 10 min Reference on right shoulder Cross-over | − | Left fronto-temporal (crossing point between T3-Fz and F7-Cz)* | Picture naming task | Picture naming accuracy after c-tDCS whereas a-tDCS and sham induced no changes |
| Baker et al., 2010 | 10 | Chronic | a-tDCS and sham 1 mA 5 days/condition 20 min/day Reference on right shoulder Cross-over Online anomia treatment4 | − | fMRI-guided left frontal areas | Picture naming task, WAB-R, ABA-2 | Naming accuracy after a-tDCS compared to sham; effects persisted at least 1-week post-treatment |
| Fiori et al., 2011 | 3 | Chronic | a-tDCS and sham 1 mA 20 min/day 5 days/condition Online language training | − | Left Wernicke's | Picture naming task, BADA | Picture naming accuracy with a-tDCS and sham; shorter naming latencies during a-tDCS compared to sham. Accuracy and RT were better at 1 and 3 weeks after a-tDCS |
| Fridriksson et al., 2011 | 8 | Chronic with posterior lesions | a-tDCS and sham 1 mA 5 days/condition 20 min/day Reference on right forehead Cross-over Online anomia treatment4 | − | fMRI-guided (left) perilesional areas | Picture naming task | (Reduction in) reaction times during naming after a-tDCS compared to sham; effects persisted at least 3-weeks |
| Floel et al., 2011 | 12 | Chronic | a-tDCS, c-tDCS, and sham 1 mA 20 min/day 3 days/condition Cross-over Reference in contralateral supraorbital Online anomia training | − | Right temporo-parietal | AAT; picture naming | Picture naming accuracy after all stimulation conditions observed with anomia training; sustained benefits were found 2-weeks after a-tDCS as compared to sham and c-tDCS |
| You et al., 2011 | 7 a-tDCS 7 c-tDCS 7 sham | Sub-acute | a-tDCS on left or c-tDCS on right or sham 2 mA 10 days 30 min Reference on contralateral supraorbital Online SLT | − | Left and Right Wernicke's (STG) | K-WAB | Auditory verbal comprehension after right c-tDCS compared to left a-tDCS and sham; overall improvement in AQ and spontaneous speech also observed across groups |
| Kang et al., 2011 | 10 | Chronic | c-tDCS and sham 2 mA 20 min 5 days/condition Cross-over Reference on left supraorbital Online word-retrieval training | − | Right Broca's homolog | Korean-BNT | Naming accuracy at 1 h after c-tDCS but no changes in sham tDCS |
| Marangolo et al., 2013 | 12 | Chronic | a-tDCS and sham 1 mA 20 min 10 day/condition Reference on right frontopolar Cross-over Online conversational therapy | 1 | Left Broca's (F4)* and Wernicke's (CP5)* | BADA, token test, ecological measure, attention and memory tests | Informative speech–increase in content-units, verb and sentence production– after a-tDCS on left Broca's area; effects sustained up to 3 months |
CPAP, Continuous Positive Airway Pressure; AAT, Aachen Aphasia Test; ABA-2, Apraxia Battery for Adults—Second Edition; AMT, Active Motor Threshold; ASRS, Aphasia Severity Rating Scale; a-tDCS, anodal transcranial direct current stimulation; BADA, Battery for the Analysis of Aphasic Disorders; BDAE, Boston Diagnostic Aphasia Examination; BNT, Boston Naming Test; CAL, Communicative Abilities Log; CompId, Complex Ideation subtest; COWAT, Controlled Oral Word Association Test; cTBS, Continuous Theta Burst Stimulation (inhibitory rTMS protocol); c-tDCS, cathodal transcranial direct current stimulation; ctrl, control; dlPFC, Dorsolateral prefrontal cortex; DTI-FA, Diffusion Tensor Imaging—Fractional Anisotropy; EEG, Electroencephalogram; FU, Follow-up in months after treatment; IFG, Inferior frontal gyrus; iTBS, intermittent theta burst stimulation; J-WAB, Japanese-Western Aphasia Battery; K-WAB, Korean-Western Aphasia Battery; LI, Lateralization index; mA, milliamperes (unit of current); PET, Positron emission tomography; PPVT, Peabody Picture Vocabulary Test; PTr, Pars triangularis (Anterior portion of Broca's area); RMT, Resting Motor Threshold; SFT, Semantic Fluency Test; SJT, Word, picture semantic judgment task; SLT, Speech language therapy; SLTA, Standard Language Test of Aphasia; STG, Superior temporal gyrus; WAB-R, Western Aphasia Battery—Revised.
*
EEG International 10–20 system.