Healthy
Conditions
Keywords
Volunteers
Brief summary
This study will investigate whether transcranial direct current stimulation enhances the effects of cognitive training in healthy older adults.
Detailed description
The current study will investigate methods for enhancing cognitive training effects in healthy older adults by employing a combination of interventions facilitating neural plasticity and optimizing readiness for learning. Adults over the age of 65 represent the fastest growing group in the US population. As such, age-related cognitive decline represents a major concern for public health. Recent research suggests that cognitive training in older adults can improve cognitive performance, with effects lasting up to 10 years. However, these effects are typically limited to the tasks trained, with little transfer to other cognitive abilities or everyday skills. A pilot randomized clinical trial will examine the individual and combined impact of pairing cognitive training with transcranial direct current stimulation (tDCS). tDCS is a method of non-invasive brain stimulation that directly stimulates brain regions involved in active cognitive function and enhances neural plasticity when paired with a training task. We will compare changes in cognitive and brain function resulting from CT and CT combined with tDCS using a comprehensive neurocognitive, clinical, and multimodal neuroimaging assessment of brain structure, function, and metabolic state.
Interventions
Administer 30 seconds of 2 mA electrical current to the head through saline soaked electrodes.
Participants will undergo 20 minutes of 2 mA electrical stimulation to the head through saline soaked electrodes.
Sponsors
Study design
Eligibility
Inclusion criteria
* Men and women * Age: 65 to 90 years * English speaking * Physically mobile * working memory function between 0-75th percentile determined by screening results on the POSIT Baseline Cognitive Training computerized tasks.
Exclusion criteria
* Neurological disorders (e.g., dementia, stroke, seizures, traumatic brain injury). * Evidence of dementia (NACC UDS scores of 1.5 standard deviations below the mean for age, sex and education adjusted norms in a single cognitive domain on the task). * Past opportunistic brain infection. * Major psychiatric illness (schizophrenia, intractable affective disorder, current substance dependence diagnosis or severe major depression and/or suicidality). * Unstable (e.g., cancer other than basal cell skin) and chronic (e.g, severe diabetes) medical conditions. * MRI contraindications (e.g., pregnancy, claustrophobia, metal implants that are contraindicated for MRI). * Physical impairment precluding motor response or lying still for 1 hr and inability to walk two blocks without stopping. * Certain prescription medications may possibly reduce effects otherwise induced by the tDCS stimulation protocol. * Hearing or vision deficits that will not allow for standardized cognitive training. * Left handedness
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in NIH Toolbox Fluid Cognition Composite Score | baseline up to two week post test | The NIH Toolbox is a battery of neurocognitive tests created by the National Institute on Aging as a comprehensive measure of cognitive function. We used the change from baseline to two week post test in the NIH Toolbox Fluid Cognition Composite Score (FCC) to assess outcome. The uncorrected standard score of the FCC was used. The FCC is derived by averaging the standard scores of the NIH Toolbox Flanker, Dimensional Change Card Sort, Picture Sequence Memory, List Sorting, and Pattern Comparison tests and then deriving standard scores based on this new distribution. The uncorrected standard score is on a scale of mean = 100, standard deviation = 15. Higher positive scores mean a greater improvement at the post test. Difference scores ranged from a minimum of -7 to a maximum of 19. FCC scores ranged from a minimum of 73 to a maximum of 112 in this sample. On a population level percentiles are reported from a minimum score of 59 to a maximum of 140, covering 99.3% of the population. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Cognitive Training + Active tDCS Participants will undergo up to 10 hours of cognitive training. Cognitive training will involve computerized games that stress elements of cognition. The group will undergo active transcranial direct current stimulation.
Transcranial Direct Current Stimulation: Participants will undergo 20 minutes of 2 mA electrical stimulation to the head through saline soaked electrodes. | 15 |
| Cognitive Training + Sham tDCS Participants will undergo up to 10 hours of cognitive training. Cognitive training will involve computerized games that stress elements of cognition. The group will undergo sham transcranial direct current stimulation.
Sham Stimulation: Administer 30 seconds of 2 mA electrical current to the head through saline soaked electrodes. | 16 |
| Total | 31 |
Baseline characteristics
| Characteristic | Cognitive Training + Sham tDCS | Total | Cognitive Training + Active tDCS |
|---|---|---|---|
| Age, Continuous | 73.9 years STANDARD_DEVIATION 6.7 | 73.6 years STANDARD_DEVIATION 7.1 | 73.3 years STANDARD_DEVIATION 7.6 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 2 Participants | 3 Participants | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 14 Participants | 28 Participants | 14 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| NIH toolbox fluid cognition uncorrected standard score | 88.9 units on a scale STANDARD_DEVIATION 12.3 | 90.9 units on a scale STANDARD_DEVIATION 10.7 | 93.0 units on a scale STANDARD_DEVIATION 8.6 |
| Race/Ethnicity, Customized African American | 0 Participants | 1 Participants | 1 Participants |
| Race/Ethnicity, Customized Caucasian | 14 Participants | 28 Participants | 14 Participants |
| Race/Ethnicity, Customized Latino | 1 Participants | 1 Participants | 0 Participants |
| Race/Ethnicity, Customized Other | 1 Participants | 1 Participants | 0 Participants |
| Region of Enrollment United States | 16 participants | 31 participants | 15 participants |
| Sex: Female, Male Female | 9 Participants | 17 Participants | 8 Participants |
| Sex: Female, Male Male | 7 Participants | 14 Participants | 7 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 15 | 0 / 16 |
| other Total, other adverse events | 0 / 15 | 0 / 16 |
| serious Total, serious adverse events | 0 / 15 | 1 / 16 |
Outcome results
Change in NIH Toolbox Fluid Cognition Composite Score
The NIH Toolbox is a battery of neurocognitive tests created by the National Institute on Aging as a comprehensive measure of cognitive function. We used the change from baseline to two week post test in the NIH Toolbox Fluid Cognition Composite Score (FCC) to assess outcome. The uncorrected standard score of the FCC was used. The FCC is derived by averaging the standard scores of the NIH Toolbox Flanker, Dimensional Change Card Sort, Picture Sequence Memory, List Sorting, and Pattern Comparison tests and then deriving standard scores based on this new distribution. The uncorrected standard score is on a scale of mean = 100, standard deviation = 15. Higher positive scores mean a greater improvement at the post test. Difference scores ranged from a minimum of -7 to a maximum of 19. FCC scores ranged from a minimum of 73 to a maximum of 112 in this sample. On a population level percentiles are reported from a minimum score of 59 to a maximum of 140, covering 99.3% of the population.
Time frame: baseline up to two week post test
Population: 1 participant in the Cognitive Training + Sham tDCS group listed in the baseline characteristics section withdrew prior to post test, reducing the number from 16 to 15 in this group.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Cognitive Training + Active tDCS | Change in NIH Toolbox Fluid Cognition Composite Score | 4.7 units on a scale | Standard Deviation 7.9 |
| Cognitive Training + Sham tDCS | Change in NIH Toolbox Fluid Cognition Composite Score | 6.1 units on a scale | Standard Deviation 5.5 |