Spectral Characteristics of Memory Transformation

Study Overview
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Brief Summary
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Sometimes, it is necessary to re-learn a previously learned movement behavior, for example, a bad posture during the golf drive or while playing the piano. Unlearning or relearning an intensively trained behavior is particularly important if the behavior is hampering recovery, for example, in chronic pain or after a stroke. With this pilot study, the brain mechanisms that control the change of pre-existing stable memories of a motor skill will be tested with electroencephalography (EEG). Non-invasive brain stimulation will be used to modulate these brain mechanisms and test if it is possible to change the pre-existing motor memory and the learning of a new motor skill.

Official Title
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Probing Mechanisms of Procedural Memory Transformation With Cross-frequency Transcranial Alternating Current Stimulation (Cf-tACS) as an Avenue to Sculpt Sensorimotor Behavior

Conditions
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Healthy

Intervention / Treatment
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* Other: Transcranial alternating current stimulation (tACS) combined with behavioral intervention
* Other: Inactive (sham) stimulation combined with behavioral intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years or older (2/3 of the final sample will be ≥60years of age) No previous stroke, brain tumor, neurodegenerative disease, or trauma to the head Ability to give consent for study participation who have access to a personal computer with internet Exclusion Criteria: • Pregnancy Inability to use all ten fingers to type on a standard computer keyboard Uncorrected vision, hindering perception of visual cues presented on a standard computer screen Medication use at the time of study that may interfere with learning or the effect of tACS, including but not limited to carbamazepine, flunarizine, sulpiride, rivastigmine, dextromethorphan; Neuromuscular disorders affecting hand and finger movements necessary for 10-finger keyboard typing Presence of neurological or psychiatric disorders Presence of scalp injury or disease Prior history of seizures Prior intracranial surgery Prior brain radiotherapy Prior history of intracranial tumor, intracranial infection, or cerebrovascular malformation Metal in head or neck Contraindications to MRI (such as severe claustrophobia, implanted medical devices)

Ages Eligible for Study
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Minimum Age: 18 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Active non-invasive brain stimulation during behavioral memory interference<br>Non-invasive brain stimulation with transcranial alternating current stimulation will be applied during a memory interference intervention. | Other: Transcranial alternating current stimulation (tACS) combined with behavioral intervention<br>* Transcranial alternating current stimulation (tACS) combined with behavioral intervention (memory interference).<br>|
| Sham Comparator: Sham stimulation during behavioral memory interference<br>Inactive (sham) stimulation will be applied during a memory interference intervention. | Other: Inactive (sham) stimulation combined with behavioral intervention<br>* Inactive (sham) stimulation combined with behavioral intervention (memory interference)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Behavioral: interference rate | Change in performance precision of a previously learned sensorimotor skill | before - after one single intervention (1 hour) | 
| Neural: brain connectivity change | Change in EEG-derived markers of brain activation and connectivity | before - after one single intervention (1 hour) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Behavioral: interference rate | Change in performance precision of a previously learned sensorimotor skill | before - after one single intervention (24 hour follow-up) | 
| Neural: brain connectivity change | Change in EEG-derived markers of brain activation and connectivity | before - after one single intervention (24 hour follow-up) |