HDtDCS in Logopenic Variant PPA: Effects on Language and Neural Mechanisms
Study Details
Study Description
Brief Summary
This study aims to evaluate the effectiveness of a therapy called High-Definition Transcranial Direct Current Stimulation (HD-tDCS) for the treatment of the language deficits experienced by people with a type of Primary Progressive Aphasia. This study uses a combination of brain imaging, language assessment, language training sessions, and HD-tDCS therapy as well as placebo therapy sessions.
Condition or Disease | Intervention/Treatment | Phase |
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N/A |
Detailed Description
The logopenic variant of Primary Progressive Aphasia (lvPPA) is an untreatable neurodegenerative disorder that is often referred to as the 'language form' of Alzheimer's Disease (AD). Transcranial Direct Current Stimulation (tDCS) has emerged as a safe and potentially effective tool that appears to enhance language production when delivered during language training. This technology provides a critical opportunity to conduct disease intervention.
In this study, the investigators will test the hypothesis that High-Definition tDCS (HD-tDCS) will improve performance on language tasks by increasing functional connectivity and by regulating abnormal neuronal oscillatory patterns. The rationale for this project is that a determination of the therapeutic efficacy and the associated neural mechanisms of HD-tDCS in lvPPA is likely to offer a scientific framework whereby new stimulation parameters, conditions, and target sites can be deciphered.
This study will test the hypothesis that HD-tDCS will improve performance on language tasks by increasing functional connectivity and by regulating abnormal neuronal oscillatory patterns. The language performance and functional connectivity changes will be determined in a randomized, double-blind, sham-controlled crossover manner, in which a stimulation of up to 2mA in the targeted cortical tissue or sham is administered to 20 lvPPA subjects age 45 years and older. The order of treatments is counterbalanced in a within-subject crossover design. In brief, study participants will receive sham during one treatment period and stimulation during the other treatment period.
Study Design
Arms and Interventions
Arm | Intervention/Treatment |
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Experimental: HD-tDCS, then Sham Subjects receive High Dose transcranial Direct Current Stimulation (HD-tDCS) lasting 20 minutes at an electric current intensity of up to 2mA in the left posterior temporo-parietal cortex (TPC). Stimulation sessions are delivered once a day (QD) for a total of 10 sessions over 2 weeks (Monday-Friday). After a washout period of 16 weeks, subjects receive Sham sessions (no electric current) once a day (QD) for a total of 10 sessions over 2 weeks (Monday-Friday). |
Device: HD-tDCS
High-Dose transcranial Direct Current Stimulation
Other Names:
Device: Sham
Sham sessions (no electric current)
|
Experimental: Sham, then HD-tDCS Subjects receive Sham sessions (no electric current) once a day (QD) for a total of 10 sessions over 2 weeks (Monday-Friday). After a washout period of 16 weeks, subjects receive High Dose transcranial Direct Current Stimulation (HD-tDCS) lasting 20 minutes at an electric current intensity of up to 2mA in the left posterior temporo-parietal cortex (TPC). Stimulation sessions are delivered once a day (QD) for a total of 10 sessions over 2 weeks (Monday-Friday). |
Device: HD-tDCS
High-Dose transcranial Direct Current Stimulation
Other Names:
Device: Sham
Sham sessions (no electric current)
|
Outcome Measures
Primary Outcome Measures
- Language Performance on seven cognitive assessments: Picture Naming, Letter & Category Fluency, Digit Span Test, Phonological Short-term Memory Test, Word and non-word rhyme matching, Spontaneous Speech Sample, and Communicative Effectiveness Index. [2 weeks]
Language performance changes as assessed at baseline and after tDCS stimulation procedures as measured by the seven assessments listed above. Scores across all tests within the language battery will be combined into one composite measure to facilitate assessment of overall language performance across domains. All seven scores will be normalized to a Z-score by transforming individual raw test scores according to the mean and standard deviation of the scores for all subjects. Then, Z-scores of each test will be averaged to obtain an individual composite language Z-score (McConathey et al., 2017). We will employ age, years of education, gender, and gray matter (GM) volume as time-invariant covariates to obtain residual variables to determine the LG changes due to stimulation. We will model the LG score as a function of these nuisance regressors. This regression will be performed using all the data (i.e., all subjects, all groups, and all times).
Secondary Outcome Measures
- Brain Connectivity as seen on fMRI (functional MRI) [2 weeks]
Changes in brain functional connectivity as assessed at baseline and after tDCS stimulation as measured on fMRI
- Neuronal Frequencies and Synchronizations as seen on rsMEG (resting state MEG) [2 weeks]
Changes in abnormal patterns of neuronal frequencies and synchronizations as assessed at baseline and after tDCS stimulation procedures as measured on rsMEG. Connectivity between all ROI-pairs (Region of Interest) will be calculated in the theta (4-8 Hz), alpha (8-12 Hz), beta (13-30 Hz), and low-gamma (30-55 Hz) frequency bands using three different metrics: coherence (COH), phase lag index (PLI), and debiased weighted phase lag index (d-wPLI). Mean connection strengths within 3 intra-hemispheric language-specific ROI-groups, and those between all intra-hemispheric ROIs will be computed. We will also compute mean connection strengths between language ROI-groups and all remaining brain ROIs, and those between each hemispheric ROI and all other brain ROIs.
Eligibility Criteria
Criteria
Inclusion Criteria:
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Diagnosed with language variant Primary Progressive Aphasia (lvPPA) subtype, defined as either clinical lvPPA or imaging-supported lvPPA in accordance with the most recent diagnostic criteria (Mesulam., 2001; Gorno-Tempini et al., 2011).
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Fluent in English.
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45 years of age or older.
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Structural brain MRI performed within 3 years prior to enrollment.
Exclusion Criteria:
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Severe cognitive, auditory or visual impairments that would preclude cognitive testing.
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Presence of major untreated or unstable psychiatric disease.
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A chronic medical condition that is not treated or is unstable.
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The presence of cardiac stimulators or pacemakers.
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Any metal implants in the skull
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Contraindications to MRI
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History of seizures
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History of dyslexia or other developmental learning disabilities.
Contacts and Locations
Locations
Site | City | State | Country | Postal Code | |
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1 | The Medical College of Wisconsin | Milwaukee | Wisconsin | United States | 53226 |
Sponsors and Collaborators
- Medical College of Wisconsin
Investigators
- Principal Investigator: Elias Granadillo, The Medical College of Wisconsin
Study Documents (Full-Text)
None provided.More Information
Publications
- Abel S, Weiller C, Huber W, Willmes K, Specht K. Therapy-induced brain reorganization patterns in aphasia. Brain. 2015 Apr;138(Pt 4):1097-112. doi: 10.1093/brain/awv022. Epub 2015 Feb 15.
- Dancause N, Barbay S, Frost SB, Plautz EJ, Chen D, Zoubina EV, Stowe AM, Nudo RJ. Extensive cortical rewiring after brain injury. J Neurosci. 2005 Nov 2;25(44):10167-79.
- Datta A, Bansal V, Diaz J, Patel J, Reato D, Bikson M. Gyri-precise head model of transcranial direct current stimulation: improved spatial focality using a ring electrode versus conventional rectangular pad. Brain Stimul. 2009 Oct;2(4):201-7, 207.e1.
- Datta A, Truong D, Minhas P, Parra LC, Bikson M. Inter-Individual Variation during Transcranial Direct Current Stimulation and Normalization of Dose Using MRI-Derived Computational Models. Front Psychiatry. 2012 Oct 22;3:91. doi: 10.3389/fpsyt.2012.00091. eCollection 2012.
- Edwards D, Cortes M, Datta A, Minhas P, Wassermann EM, Bikson M. Physiological and modeling evidence for focal transcranial electrical brain stimulation in humans: a basis for high-definition tDCS. Neuroimage. 2013 Jul 1;74:266-75. doi: 10.1016/j.neuroimage.2013.01.042. Epub 2013 Jan 28.
- Gorno-Tempini ML, Brambati SM, Ginex V, Ogar J, Dronkers NF, Marcone A, Perani D, Garibotto V, Cappa SF, Miller BL. The logopenic/phonological variant of primary progressive aphasia. Neurology. 2008 Oct 14;71(16):1227-34. doi: 10.1212/01.wnl.0000320506.79811.da. Epub 2008 Jul 16.
- Hogeveen J, Grafman J, Aboseria M, David A, Bikson M, Hauner KK. Effects of High-Definition and Conventional tDCS on Response Inhibition. Brain Stimul. 2016 Sep-Oct;9(5):720-729. doi: 10.1016/j.brs.2016.04.015. Epub 2016 Apr 22.
- Kuo HI, Bikson M, Datta A, Minhas P, Paulus W, Kuo MF, Nitsche MA. Comparing cortical plasticity induced by conventional and high-definition 4 × 1 ring tDCS: a neurophysiological study. Brain Stimul. 2013 Jul;6(4):644-8. doi: 10.1016/j.brs.2012.09.010. Epub 2012 Oct 13.
- Meyer AM, Snider SF, Campbell RE, Friedman RB. Phonological short-term memory in logopenic variant primary progressive aphasia and mild Alzheimer's disease. Cortex. 2015 Oct;71:183-9. doi: 10.1016/j.cortex.2015.07.003. Epub 2015 Jul 16.
- Muthalib M, Besson P, Rothwell J, Perrey S. Focal Hemodynamic Responses in the Stimulated Hemisphere During High-Definition Transcranial Direct Current Stimulation. Neuromodulation. 2018 Jun;21(4):348-354. doi: 10.1111/ner.12632. Epub 2017 Jul 17.
- Pillay SB, Stengel BC, Humphries C, Book DS, Binder JR. Cerebral localization of impaired phonological retrieval during rhyme judgment. Ann Neurol. 2014 Nov;76(5):738-46. doi: 10.1002/ana.24266. Epub 2014 Sep 19.
- Richardson J, Datta A, Dmochowski J, Parra LC, Fridriksson J. Feasibility of using high-definition transcranial direct current stimulation (HD-tDCS) to enhance treatment outcomes in persons with aphasia. NeuroRehabilitation. 2015;36(1):115-26. doi: 10.3233/NRE-141199.
- Rogalski E, Cobia D, Harrison TM, Wieneke C, Weintraub S, Mesulam MM. Progression of language decline and cortical atrophy in subtypes of primary progressive aphasia. Neurology. 2011 May 24;76(21):1804-10. doi: 10.1212/WNL.0b013e31821ccd3c.
- Sonty SP, Mesulam MM, Weintraub S, Johnson NA, Parrish TB, Gitelman DR. Altered effective connectivity within the language network in primary progressive aphasia. J Neurosci. 2007 Feb 7;27(6):1334-45.
- Tippett DC, Hillis AE, Tsapkini K. Treatment of Primary Progressive Aphasia. Curr Treat Options Neurol. 2015 Aug;17(8):362. doi: 10.1007/s11940-015-0362-5.
- Villamar MF, Volz MS, Bikson M, Datta A, Dasilva AF, Fregni F. Technique and considerations in the use of 4x1 ring high-definition transcranial direct current stimulation (HD-tDCS). J Vis Exp. 2013 Jul 14;(77):e50309. doi: 10.3791/50309.
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