Table 2.
tDCS Studies in Aphasia
| Study | N | N Lesion Location | Time Since Stroke | Aphasia Type(s) | Location(s) Stimulated | Stimulation Parameters | Outcome Measure | Results |
|---|---|---|---|---|---|---|---|---|
| Monti et al., 2008 | 8 | Left frontal cortical/subcortical lesions (n=3); frontoparietal cortical/subcortical lesions (n=2); 8 frontotemporoparietal cortical/subcortical lesions (n=2); frontoparietal subcortical lesion | 2–8 years | Broca’s aphasia (n=4); global aphasia (n=4) | Broca’s area; occipital lobe control site | Single session of anodal, cathodal, and sham tDCS over Broca’s area at 1 mA for 20 min; cathodal and sham tDCS applied to occipital lobe in separate experiment | Picture naming | Improved picture naming accuracy immediately after cathodal tDCS of Broca’s area but not anodal, sham, or occipital tDCS |
| Fiori et al., 2010 | 3 | Left frontoparietal subcortical lesion (n=1); frontoparietal 3 cortical/subcortical lesion (n=1); large frontotemporoparietal cortical/subcortical lesion (n=1) | ~2–6 years | Mild (n=1), moderate (n=1), and severe (n=1) nonfluent aphasia | Wernicke’s area | 5 consecutive daily sessions of anodal (1 mA for 20 min) or sham tDCS paired with language therapy | Picture naming | Improved naming accuracy and reaction time after 5 days of anodal but not sham tDCS. In 2 subjects, improvements persisted at 1 and 3 weeks after stimulation |
| Baker et al., 2010 | 10 | Left temporoparietal lesions (n=4); frontotemporal lesions (n=3); frontotemporoparietal lesion (n=1); 10 temporoparietooccipital lesion (n=1); Lesion of entire MCA territory, medial frontal lobe, and basal ganglia (n=1) | ~1–20 years | Anomic aphasia (n=6), Broca’s aphasia (n=4) | tDCS localization guided to left hemisphere targets by fMRI activation during an overt naming task: premotor cortex (n=5), dorsolateral prefrontal cortex (n=2), anterior prefrontal cortex (n=1), pars triangularis (n=1), pars opercularis (n=1) | 5 consecutive daily sessions of anodal (1 mA for 20 min) or sham tDCS paired with anomia therapy | Picture naming | Improved picture naming after anodal tDCS compared to sham stimulation; persistent benefits 1 week after treatment |