Healthy
Conditions
Keywords
memory, metacognition, metamemory, transcranial direct current stimulation
Brief summary
When people learn and remember information, it is often accompanied by a feeling of subjective confidence about whether or not information has been learned and accurately remembered. These subjective feelings of confidence are often related to actual memory performance, but are sometimes incorrect. The investigators have previously shown that applying high definition transcranial direct current stimulation (HD-tDCS) over the dorsolateral prefrontal cortex leads to more accurate feelings of subjective confidence, at least when subjects are asked for their confidence about future memory performance. Accurate confidence judgments are useful in that they may later subsequent behavior, and inaccurate ones may be costly. For example, a student who erroneously believes that studied material was learned may stop studying and not do well on a test. Individuals who have a feeling-of-knowing about the answer to a general knowledge question will continue to search their memory, whereas individuals who do not have a feeling-of-knowing will stop searching their memory. Individuals who are confident they know the answer to a question are more likely to answer it. In this study, the experimenters are testing the effects of brain stimulation on subjective awareness of memory (termed metamemory monitoring) and how people use those subjective judgments (termed metamemory control). The approach taken is to have participants visit the laboratory on 3 visits and receive brain stimulation while completing memory and metamemory tasks.
Interventions
DEVICEHD-tDCS
Participants will complete a metamemory and memory task
Sponsors
National Institute of General Medical Sciences (NIGMS)
Brooklyn College of the City University of New York
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy, right-handed adults ages 18-35. English spoken since age 5. Normal or corrected-to-normal vision.
Exclusion criteria
* Participants will be excluded if they have chronic skin disease or a medical skin condition, or an unhealed open wound on the scalp, face, neck, or forehead near the electrode location. * Participants will be excluded if they self-report significant medical, neurological, or psychiatric illness and/or a history of substance abuse
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Memory Control Advantage Index | Through study completion, an average of 3 weeks | This indexes the memory advantage for choosing which general knowledge question one receives a hint about the answer to versus having the experimenter choose which general knowledge question one receives a hint about the answer. The investigators will subtract the proportion of correctly recognized general knowledge answers for experimenter-chosen questions from the proportion correctly recognized for participant-chosen questions |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| semantic recognition as assessed by a general knowledge task | Through study completion, an average of 3 weeks | Differences in recognition are compared between each condition (each active HD-tDCS and sham). |
| semantic recall as assessed by a general knowledge task | Through study completion, an average of 3 weeks | Differences in recall are compared between each condition (each active HD-tDCS and sham). |
| Feeling-of-knowing ratings and their accuracy | Through study completion, an average of 3 weeks | Feeling of knowing ratings are given on a scale. To assess the accuracy of these ratings, the subjective ratings are compared to objective accuracy, using signal detection based measures. Differences in feeling-of-knowing ratings and their accuracy are compared between each condition (each active HD-tDCS and sham). |
Countries
United States
Outcome results
None listed