Dataset Information

Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

ABSTRACT: BACKGROUND:Transcranial direct current stimulation (tDCS) is an in-demand form of neuromodulation generally regarded as safe and well tolerated. However, few studies have examined the safety, tolerability, or blinding of High Definition (HD-) tDCS, especially in older adults and at stimulation intensities of 2 milliamps (mA) or greater. OBJECTIVE:We examined the rates of serious adverse events and common side effects to establish safety and tolerability, respectively, in HD-tDCS. Blinding was evaluated using participants' accuracy in correctly stating their condition (i.e., active or sham). METHODS:The sample included 101 older adults (Mage?=?69.69, SD?=?8.33; Meduc?=?16.27, SD?=?2.42) who participated in our double blind randomized controlled studies or in case studies that used HD-tDCS for 20-30?min at 2?mA (n?=?66, 31 active) or 3?mA (n?=?35, 20 active). Participants completed a standardized side effect questionnaire and were asked whether they received active or sham stimulation at the end of each session. RESULTS:There were no serious adverse events and no participants withdrew, suggesting that HD-tDCS meets basic safety parameters. Tolerability was comparable between active and sham HD-tDCS regardless of intensity (2?mA and 3?mA) in first session (allp?>?.09). Tingling was the most commonly endorsed item (59% active; 56% sham) followed by burning sensation (51% active; 50% sham), the majority of which were mild in nature. "Severe" ratings were reported in fewer than 4% of sessions. Blinding appeared adequate since there were no significant group differences between individuals correctly stating their stimulation condition (?2?=?0.689, p?=?.679). The above tolerability and blinding findings generally persisted when multiple session data (i.e., 186 total sessions) were considered. CONCLUSIONS:HD-tDCS appears well-tolerated and safe with effective sham-control in older adults, even at 3?mA. These data support the use of HD-tDCS in randomized controlled trials and clinical translation efforts.

SUBMITTER: Reckow J

PROVIDER: S-EPMC6512313 | biostudies-literature | 2018 Sep - Oct

REPOSITORIES: biostudies-literature

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Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

Reckow Jaclyn J Rahman-Filipiak Annalise A Garcia Sarah S Schlaefflin Stephen S Calhoun Oliver O DaSilva Alexandre F AF Bikson Marom M Hampstead Benjamin M BM

Brain stimulation 20180504 5

<h4>Background</h4>Transcranial direct current stimulation (tDCS) is an in-demand form of neuromodulation generally regarded as safe and well tolerated. However, few studies have examined the safety, tolerability, or blinding of High Definition (HD-) tDCS, especially in older adults and at stimulation intensities of 2 milliamps (mA) or greater.<h4>Objective</h4>We examined the rates of serious adverse events and common side effects to establish safety and tolerability, respectively, in HD-tDCS. ...[more]

PMID: 29784589

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Dataset Information

Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

Publications

Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

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