Improving Working Memory in Older Adults

Study Overview
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Brief Summary
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The research program will evaluate the theoretical claim that age-related memory and cognitive decline in humans result from the inefficient orchestration of rhythmic activity within large-scale cortical networks. The results will contribute to the basic science groundwork for developing future non-pharmacological interventions aimed at boosting memory and cognition in aging and clinical populations.

Detailed Description
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We hypothesize that aged-related memory and cognitive impairments emerge from large-scale functional dysconnectivity, and by stimulating the brain noninvasively with extremely weak levels of electrical current, we may be able to re-synchronize connectivity and stabilize or improve memory and cognitive function, measured behaviorally. The experiments of this project are proposed as between-subjects, sham-controlled, and double-blind in design, and use noninvasive electroencephalographic (EEG) measurements of rhythmic brain activity. The experimental intervention involves the application of low-intensity, high-definition, transcranial electrical current stimulation while subjects perform a variety of computer-based tasks that probe memory and cognitive function.

Official Title
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Improving Working Memory in Older Adults by Restoring Large-Scale Cortical Interactions

Conditions
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Large-scale Physiological Foundations of Memory Decline in Aging Humans

Intervention / Treatment
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* Device: High definition transcranial electrical current stimulation


Participation Criteria
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Eligibility Criteria
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The following general inclusion criteria apply to all subjects: must be between the ages of 68-80 (except for Experiment 1 where subjects must be between the ages of 18-30), have normal or corrected-to-normal vision, color vision, nonpregnant, no metal implants in head, no implanted electronic devices, no history of neurological problems or head injury, no skin sensitivity, no claustrophobia, no dementia (normal Mini Mental State Examination between 24-30; Montreal Cognitive Assessment > 25), no depression (normal Beck Depression Inventory II <13; Geriatric Depression Scale < 10), and cannot be taking any psychoactive medication.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: active stimulation<br> | Device: High definition transcranial electrical current stimulation<br>* Low-intensity and safe, noninvasive application of electrical current to the human scalp with the goal of gradually modulating levels of neuronal excitability.<br>|
| Sham Comparator: sham stimulation<br> | Device: High definition transcranial electrical current stimulation<br>* Low-intensity and safe, noninvasive application of electrical current to the human scalp with the goal of gradually modulating levels of neuronal excitability.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Memory performance success (sham stimulation condition) | The accuracy of task performance (in percentage correct units) in the delayed-match-to-sample working memory paradigm | During sham intervention | 
| Memory performance success (active stimulation condition) | The accuracy of task performance (in percentage correct unit) in the delayed-match-to-sample working memory paradigm | During active intervention | 
| Memory performance speed (sham stimulation condition) | The reaction time of task performance (in millisecond units) in the delayed-match-to-sample working memory paradigm | During sham intervention | 
| Memory performance speed (active stimulation condition) | The reaction time of task performance (in millisecond units) in the delayed-match-to-sample working memory paradigm | During active intervention |