| Language | German |
| Inclusion criteria | L hand motor area spared; mild aphasia |
| Number of individuals with aphasia | 16 |
| Number of control participants | 16 |
| Were any of the participants included in any previous studies? | No |
| Is age reported for patients and controls, and matched? | Yes (mean 56.7 ± 10.1 years) |
| Is sex reported for patients and controls, and matched? | Yes (males: 10; females: 6) |
| Is handedness reported for patients and controls, and matched? | Yes (right: 16; left: 0) |
| Is time post stroke onset reported and appropriate to the study design? | Yes (mean 54.3 ± 45.3 months, range 12-169 months) |
| To what extent is the nature of aphasia characterized? | Comprehensive battery |
| Language evaluation | AAT |
| Aphasia severity | Mild |
| Aphasia type | Not stated |
| First stroke only? | Not stated |
| Stroke type | Not stated |
| To what extent is the lesion distribution characterized? | Lesion overlay |
| Lesion extent | Range 9.7-165.1 cc |
| Lesion location | L MCA not including hand motor area |
| Participants notes | — |
| Modality | fMRI |
| Is the study cross-sectional or longitudinal? | Longitudinal—chronic treatment |
| If longitudinal, at what time point(s) were imaging data acquired? | T1/T2: chronic; tDCS and sham sessions in randomized order |
| If longitudinal, was there any intervention between the time points? | — |
| Is the scanner described? | Yes (Siemens Trio 3 Tesla) |
| Is the timing of stimulus presentation and image acquisition clearly described and appropriate? | Yes |
| Design type | Event-related |
| Total images acquired | 100 |
| Are the imaging acquisition parameters, including coverage, adequately described and appropriate? | Yes (whole brain) |
| Is preprocessing and intrasubject coregistration adequately described and appropriate? | Yes |
| Is first level model fitting adequately described and appropriate? | Yes |
| Is intersubject normalization adequately described and appropriate? | Yes |
| Imaging notes | sparse sampling |
| Language condition | Picture naming |
| Control condition | Rest |
| Are the conditions matched for visual demands? | No |
| Are the conditions matched for auditory demands? | No |
| Are the conditions matched for motor demands? | No |
| Are the conditions matched for cognitive/executive demands? | No |
| Is accuracy matched between the language and control tasks for all relevant groups? | N/A, tasks not comparable |
| Is reaction time matched between the language and control tasks for all relevant groups? | N/A, tasks not comparable |
| Behavioral data notes | — |
| Are control data reported in this paper or another that is referenced? | No |
| Does the contrast selectively activate plausible relevant language regions in the control group? | Unknown |
| Are activations lateralized in the control data? | Unknown |
| Control activation notes | — |
| Contrast notes | — |
| First level contrast | Picture naming vs rest |
| Analysis class | Cross-sectional between two groups with aphasia |
| Group(s) | Aphasia after tDCS (n = 16) vs aphasia after sham stimulation (n = 16); same patients, order counterbalanced, repeated measures |
| Covariate | — |
| Is the second level contrast valid in terms of the group(s), time point(s), and measures involved? | Somewhat (no behavioral difference) |
| Is accuracy matched across the second level contrast? | Yes, matched |
| Is reaction time matched across the second level contrast? | Yes, matched |
| Behavioral data notes | — |
| Type of analysis | Voxelwise |
| Search volume | Whole brain |
| Correction for multiple comparisons | Clusterwise correction with with GRFT and stringent voxelwise p |
| Software | SPM8 |
| Voxelwise p | .001 |
| Cluster extent | Based on GRFT |
| Statistical details | Repeated measures |
| Findings | ↓ L insula
↓ L anterior cingulate
↓ R occipital
↓ R anterior cingulate |
| Findings notes | — |
| First level contrast | Picture naming vs rest |
| Analysis class | Cross-sectional aphasia vs control |
| Group(s) | Aphasia after sham stimulation (n = 16) vs control |
| Covariate | — |
| Is the second level contrast valid in terms of the group(s), time point(s), and measures involved? | Yes |
| Is accuracy matched across the second level contrast? | Appear similar |
| Is reaction time matched across the second level contrast? | Unknown, not reported |
| Behavioral data notes | Patients named > 90% correctly in all sessions; control RT not reported |
| Type of analysis | Regions of interest (ROI) |
| ROI type | Functional |
| How many ROIs are there? | 3 |
| What are the ROI(s)? | (1) bilateral anterior cingulate; (2) L insula; (3) R lingual gyrus |
| How are the ROI(s) defined? | Regions that were less active in patients with tDCS vs sham |
| Correction for multiple comparisons | No correction |
| Statistical details | Circular because ROIs defined in one group |
| Findings | ↑ L insula
↑ L anterior cingulate
↑ R anterior cingulate |
| Findings notes | — |
| First level contrast | Picture naming vs rest |
| Analysis class | Cross-sectional aphasia vs control |
| Group(s) | Aphasia after tDCS (n = 16) vs control |
| Covariate | — |
| Is the second level contrast valid in terms of the group(s), time point(s), and measures involved? | Yes |
| Is accuracy matched across the second level contrast? | Appear similar |
| Is reaction time matched across the second level contrast? | Unknown, not reported |
| Behavioral data notes | Patients named > 90% correctly in all sessions; control RT not reported |
| Type of analysis | Regions of interest (ROI) |
| ROI type | Functional |
| How many ROIs are there? | 3 |
| What are the ROI(s)? | (1) bilateral anterior cingulate; (2) L insula; (3) R lingual gyrus |
| How are the ROI(s) defined? | Regions that were less active in patients with tDCS vs sham |
| Correction for multiple comparisons | No correction |
| Statistical details | Circular because ROIs defined in one group |
| Findings | None |
| Findings notes | — |
| First level contrast | Picture naming vs rest |
| Analysis class | Cross-sectional between two groups with aphasia |
| Group(s) | Aphasia after tDCS (n = 16) vs aphasia after sham stimulation (n = 16); same patients, order counterbalanced, repeated measures |
| Covariate | — |
| Is the second level contrast valid in terms of the group(s), time point(s), and measures involved? | Somewhat (no behavioral difference) |
| Is accuracy matched across the second level contrast? | Yes, matched |
| Is reaction time matched across the second level contrast? | Yes, matched |
| Behavioral data notes | — |
| Type of analysis | Complex |
| Statistical details | ICA was used to derive three task-relevant components: language, motor and visual. Thresholding of the functional maps is not described, but they appear to reflect coherent components of a picture naming network. These components were compared between stimulation conditions in terms of mean activity and power in three frequency bins. It should be noted that the language component is left-lateralized, unlike the model-based picture naming contrast. |
| Findings | Other |
| Findings notes | Activity in the language component was greater in the tDCS condition. In the frequency domain, the tDCS condition showed reduced power in the highest frequency bin, and increased power in the lowest frequency bin. |
| First level contrast | Picture naming vs rest |
| Analysis class | Cross-sectional aphasia vs control |
| Group(s) | Aphasia after sham stimulation (n = 16) vs control |
| Covariate | — |
| Is the second level contrast valid in terms of the group(s), time point(s), and measures involved? | Yes |
| Is accuracy matched across the second level contrast? | Unknown, not reported |
| Is reaction time matched across the second level contrast? | Unknown, not reported |
| Behavioral data notes | — |
| Type of analysis | Complex |
| Statistical details | ICA was used to derive three task-relevant components: language, motor and visual. Thresholding of the functional maps is not described, but they appear to reflect coherent components of a picture naming network. These components were compared between stimulation conditions in terms of mean activity and power in three frequency bins. It should be noted that the language component is left-lateralized, unlike the model-based picture naming contrast. |
| Findings | Other |
| Findings notes | Mean activity of these components did not differ between patients and controls. However, patients showed increased power in the middle frequency bin of the visual component. |
| First level contrast | Picture naming vs rest |
| Analysis class | Cross-sectional aphasia vs control |
| Group(s) | Aphasia after tDCS (n = 16) vs control |
| Covariate | — |
| Is the second level contrast valid in terms of the group(s), time point(s), and measures involved? | Yes |
| Is accuracy matched across the second level contrast? | Unknown, not reported |
| Is reaction time matched across the second level contrast? | Unknown, not reported |
| Behavioral data notes | — |
| Type of analysis | Complex |
| Statistical details | ICA was used to derive three task-relevant components: language, motor and visual. Thresholding of the functional maps is not described, but they appear to reflect coherent components of a picture naming network. These components were compared between stimulation conditions in terms of mean activity and power in three frequency bins. It should be noted that the language component is left-lateralized, unlike the model-based picture naming contrast. |
| Findings | None |
| Findings notes | — |
