Testing High Definition Transcranial Direct Current Stimulation (HD-tDCS) as Treatment of Mild Cognitive Impairment
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Michigan
- Enrollment
- 233
- Locations
- 2
- Primary Endpoint
- Change in Lateral Temporal Cortex Connectivity
Study Overview
Brief Summary
This study will test the effects of different doses of a form of non-invasive brain stimulation for the treatment of individuals with mild cognitive impairment (MCI) and dementia of the Alzheimer's Type (DAT).
Detailed Description
This research study is being done to learn important information about the effects of weak electrical stimulation on brain functioning in those with mild cognitive impairment (MCI) and dementia of the Alzheimer's type (DAT). The findings will help determine "how much" stimulation is needed to enhance memory and thinking abilities, how it affects brain functioning, and who is most likely to benefit. Ultimately, this information may guide treatment efforts for those at various stages of Alzheimer's disease. The study will use brain imaging to see whether these treatments change how participants learn and remember information. Functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) scans will be used. The study will also use cognitive tests and questionnaires to examine whether participants' memory (and related abilities) change because of treatment. The study will enroll participants with a diagnosis of MCI or DAT. It is expected but not required that participants will be co-enrolled in the University of Michigan Memory and Aging Project (UM-MAP; HUM00000382).
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Triple (Participant, Investigator, Outcomes Assessor)
Eligibility Criteria
- Ages
- 50 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Diagnosis of Mild Cognitive Impairment (MCI) or dementia of the Alzheimer's type (DAT)
- •Must be MRI compatible, criteria that also apply for High Definition transcranial direct current stimulation (HD-tDCS; e.g., absence of metallic or electronic implants in the upper body or head)
- •Stable on relevant medications for at least 4 weeks prior to study enrollment
Exclusion Criteria
- •Certain neurological diseases
- •Certain psychiatric conditions
- •Severe sensory impairment
Arms & Interventions
Sham Stimulation
Sham (placebo) dose of HD-tDCS treatment for 30 minutes, for between 5-30 sessions.
Intervention: Sham (Device)
1 mA Dosage Stimulation
1 milliAmp dose of HD-tDCS treatment for 30 minutes, for between 5-30 sessions.
Intervention: 1 mA HD-tDCS (Device)
2 mA Dosage Stimulation
2 milliAmp dose of HD-tDCS treatment for 30 minutes, for between 5-30 sessions.
Intervention: 2 mA HD-tDCS (Device)
3 mA Dosage Stimulation
3 milliAmp dose of HD-tDCS treatment for 30 minutes, for between 5-30 sessions.
Intervention: 3 mA HD-tDCS (Device)
Outcomes
Primary Outcomes
Change in Lateral Temporal Cortex Connectivity
Time Frame: Baseline fMRI and post-intervention (after tDCS sessions 5 & 30)
Graph Theory Analysis via fMRI using arbitrary units of connectivity strength
Change in Lateral Temporal Cortex Connectivity
Time Frame: Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).
Primary outcome focuses on default mode network (DMN) between-network functional connectivity because the lateral temporal cortex is a core component of the DMN. Between-network functional connectivity is estimated from fMRI data as strength of temporal coupling between the DMN and other high-level (association) brain networks. For each participant and time point, correlation-based connectivity (Pearson r; Fisher r-to-z transformed; arbitrary units) computed between DMN regions and other regions of the association cortex defined using standard functional atlas. Higher values reflect stronger functional connectivity between DMN and other regions. A Z-score's range is infinite. Expected value is between -3 to 3. Analyses conducted separately for amyloid negative (A-) and amyloid positive (A+) participants. Post Intervention data collection was on day 5 of treatment. Post-Expansion (PE) appointments were not consecutive. Mean time between enrollment and PE was 10 wks, longest was 43 wks.
Secondary Outcomes
- Self-Report of Contentment with Memory(Baseline and post-intervention (after tDCS sessions 5 & 30))
- Change in Overall Fluid Cognitive Abilities(Baseline and post-intervention (after tDCS sessions 5 & 30))
- Cumulative Working Memory Effects of HD-tDCS across daily sessions(Baseline Session through Session 6 then weekly up to final session)
- Cumulative Memory Reaction Time Effects of HD-tDCS across daily sessions(Baseline Session through Session 6 then weekly up to final session)
- Change in Memory Functioning(Baseline and post-intervention (after tDCS sessions 5 & 30))
- Cumulative Memory Accuracy Effects of HD-tDCS across daily sessions(Baseline Session through Session 6 then weekly up to final session)
- Self-Report of Memory Mistakes(Baseline and post-intervention (after tDCS sessions 5 & 30))
- Self-Report of Memory Strategies Used(Baseline and post-intervention (after tDCS sessions 5 & 30))
- Tolerability of HD-tDCS(Prior to and immediately following each HD-tDCS session (<60 Minutes))
- Effectiveness of Blinding of HD-tDCS(Immediately following HD-tDCS sessions 5 and final session (<60 Minutes))
- Self-Report of Contentment With Memory(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Self-Report of Memory Mistakes(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Self-Report of Memory Strategies Used(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Change in Memory Functioning(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Change in Overall Fluid Cognitive Abilities(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Cumulative Working Memory Effects of HD-tDCS Across Treatment Sessions(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Cumulative Memory Accuracy Effects of HD-tDCS Across Treatment Sessions(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Cumulative Memory Sensitivity Effects of HD-tDCS Across Daily Sessions(Baseline)
- Tolerability of HD-tDCS(Assessed immediately after each HD-tDCS session (participants received up to 30 sessions over approximately 1-12 weeks); values represent mean symptom burden averaged across all post-stimulation assessments)
- Effectiveness of Blinding of HD-tDCS(Assessed immediately after each HD-tDCS session (participants received up to 30 sessions over approximately 1-12 weeks))
- Change in Default Mode Network Connectivity(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Cumulative Cognitive Change Across Daily Consecutive Sessions(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
- Change in Global Cognition(Change from Baseline to Post-Intervention (after tDCS Session 5 - day 5 of treatment) and from Baseline to Post-Expansion (after the participant's final tDCS session beyond Session 5, up to 43 weeks).)
Investigators
Benjamin Hampstead, PhD
Stanley Berent, Ph.D., Collegiate Professor of Psychology
University of Michigan