Aphasia
Conditions
Keywords
Repetitive transcranial magnetic stimulation, Aphasia
Brief summary
In a randomized controlled trial, efficacy of low-frequency, inhibitory rTMS will be examined in rehabilitation of acquired aphasia. Two cortical sites will be targeted: Right-hemispheric homologues of Broca's and Wernicke's areas. In addition to cognitive screening prior to onset of rTMS, language assessments will be conducted before, during and after the intervention. An eyetracking-while-listening experiment will also be conducted before and after the intervention to investigate morphosyntactic processing.
Detailed description
Efficacy of low-frequency (1hz), inhibitory rTMS will be examined in rehabilitation of acquired aphasia. Two cortical sites will be targeted: Right-hemispheric homologues of Broca's and Wernicke's areas. In other words, right frontal and right temporal sites will be targeted. In addition to cognitive screening prior to onset of rTMS, language assessments will be conducted before, during and after the intervention. The language assessment will be conducted using the Turkish Aphasia Language Assessment Test (ADD) and sets of pictures used to assess naming performance. ADD will be carried out before and after the intervention. Six picture sets will be used, one at baseline, four on different days during the intervention, and the last one immediately after the last day of the intervention. Cognitive screening will be conducted at baseline using the digit span test and Raven's colored progressive matrices. In addition, a pre- and post-treatment eyetracking-while-listening experiment will be conducted to investigate morphosyntactic processing in Turkish and to examine whether the two brain stimulation interventions differentially affect online (dynamic, time-dependent) measures of morphosyntactic processing. The eyetracking paradigm will request the participants to listen to Turkish sentences varying in morphosyntactic complexity (canonical versus noncanonical sentences) and to look at the picture (out of two pictures presented on the screen) corresponding to the sentence they are listening to.
Interventions
Low frequency (1 Hz) rTMS over right inferior frontal gyrus
Low frequency (1 Hz) rTMS over right posterior superior temporal gyrus
Sponsors
Study design
Masking description
The participant and the outcomes assessor (speech and language therapist conducting the assessment tests and the eyetracking experiment) will be blind as to which experiment group the participant belongs to. The investigator / clinician providing rTMS will not be blind to the experimental condition.
Intervention model description
The two groups receive one of the two treatments: right frontal versus right temporal stimulation.
Eligibility
Inclusion criteria
* Right-handedness, * Normal or corrected-to-normal vision and hearing, * Aphasia following cerebrovascular accident, * Cerebrovascular accident at least 6 months prior to enrolment in the study, * Satisfying current TMS safety guidelines (Rossi et al. 2009, 2021), which are: * No previous history of epilepsy, * No implant (e.g., cochlear implant) or stimulator (e.g., deep brain stimulation) in the head which may interact with the magnetic field, * No use of central nervous system active drugs that lower seizure threshold (as listed in the aforementioned guidelines)
Exclusion criteria
* Left-handedness, ambidexterity, * Impaired and uncorrected vision or hearing, * No aphasia symptoms following cerebrovascular accident, * Time since cerebrovascular accident less than 6 months, * Violating current TMS safety guidelines (Rossi et al. 2009, 2021). In other words: * Having a previous history of epilepsy, * Having an implant (e.g., cochlear implant) or stimulator (e.g., deep brain stimulation) in the head which may interact with the magnetic field, * Taking central nervous system active drugs that lower seizure threshold (as listed in the aforementioned guidelines)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Turkish Aphasia Language Assessment Test Scores Time 1 (pre-treatment) | Immediately before the intervention (Day 0) | Baseline scores obtained from the Turkish Aphasia Language Assessment Test (ADD) Minimum score: 0 points Maximum score: 292 points Higher scores indicate a better outcome |
| Turkish Aphasia Language Assessment Test Scores Time 2 (during treatment) | At the end of the first week of intervention (Day 5) | Scores obtained from the Turkish Aphasia Language Assessment Test (ADD) at the end of the first week of treatment Minimum score: 0 points Maximum score: 292 points Higher scores indicate a better outcome |
| Turkish Aphasia Language Assessment Test Scores Time 3 (post-treatment short-term) | Immediately after the intervention (Day 10) | Post-treatment scores obtained from the Turkish Aphasia Language Assessment Test (ADD) at the end of the treatment Minimum score: 0 points Maximum score: 292 points Higher scores indicate a better outcome |
| Turkish Aphasia Language Assessment Test Scores Time 4 (post-treatment medium-term) | 1 month after the intervention | Post-treatment scores obtained from the Turkish Aphasia Language Assessment Test (ADD) one month after the end of the treatment Minimum score: 0 points Maximum score: 292 points Higher scores indicate a better outcome |
| Turkish Aphasia Language Assessment Test Scores Time 5 (post-treatment long-term) | 6 months after the intervention | Post-treatment scores obtained from the Turkish Aphasia Language Assessment Test (ADD) six months after the end of the treatment Minimum score: 0 points Maximum score: 292 points Higher scores indicate a better outcome |
| Picture Naming Scores Time 1 (pre-treatment) | Immediately before the intervention (Day 0) | Picture naming performance (number of accurately named pictures & naming latency for correctly named pictures) There are 20 pictures in total, of which half are objects and half actions. Minimum score: 0 points Maximum score: 20 points Higher scores indicate a better outcome |
| Picture Naming Scores Time 2 (during treatment) | At the end of the first week of intervention (Day 5) | Picture naming performance (number of accurately named pictures & naming latency for correctly named pictures) There are 20 pictures in total, of which half are objects and half actions. Minimum score: 0 points Maximum score: 20 points Higher scores indicate a better outcome |
| Picture Naming Scores Time 3 (post-treatment short-term) | Immediately after the intervention (Day 10) | Picture naming performance (number of accurately named pictures & naming latency for correctly named pictures) There are 20 pictures in total, of which half are objects and half actions. Minimum score: 0 points Maximum score: 20 points Higher scores indicate a better outcome |
| Picture Naming Scores Time 4 (post-treatment medium-term) | 1 month after the intervention | Picture naming performance (number of accurately named pictures & naming latency for correctly named pictures) There are 20 pictures in total, of which half are objects and half actions. Minimum score: 0 points Maximum score: 20 points Higher scores indicate a better outcome |
| Picture Naming Scores Time 5 (post-treatment long-term) | 6 months after the intervention | Picture naming performance (number of accurately named pictures & naming latency for correctly named pictures) There are 20 pictures in total, of which half are objects and half actions. Minimum score: 0 points Maximum score: 20 points Higher scores indicate a better outcome |
| Eye movements Time 1 (pre-treatment) | Immediately before the intervention (Day 0) | An eyetracking-while-listening paradigm will be used to determine proportions of dwell time on the correct picture (out of two alternatives) corresponding to auditorily presented Turkish sentences varying in morphosyntactic complexity. |
| Eye movements Time 2 (post-treatment) | Immediately after the intervention (Day 10) | An eyetracking-while-listening paradigm will be used to determine proportions of dwell time on the correct picture (out of two alternatives) corresponding to auditorily presented Turkish sentences varying in morphosyntactic complexity. |
Countries
Turkey (Türkiye)