Abstract
Objectives
To study the effect of anodal transcranial direct stimulation (atDCS) of the right
dorsolateral prefrontal cortex (DLPFC) on cognitive function and side effects in patients
with mild cognitive impairment.
Design
Experimental double-blind randomized, sham-controlled trial.
Setting
Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital
Participants
Volunteers (N=45) with mild cognitive impairment.
Interventions
Not applicable.
Main Outcome Measures
The atDCS group (n=23) were stimulated at 2 mA for 20 minutes with the anode on the
right DLPFC and the cathode on the left supraorbital area. The control group (n=22)
received placebo stimulation. Baseline cognitive function was assessed using the Cambridge
Neuropsychological Test Automated Battery test. Participants were treated 3 times
per week for 4 weeks (12 sessions). Cognitive function and side effects were assessed
immediately after the first stimulation, the last session, and 4 weeks after treatment.
Results
Cambridge Neuropsychological Test Automated Battery results revealed a significant
improvement in the accuracy of the visual sustained attention (VSA) in the atDCS group
at all 3 time points, the spatial working memory and visual memory (VM) immediately
after the first stimulation, and a decreased VM reaction time after 12 sessions. A
long-lasting effect on VSA and VM were found 4 weeks after treatment.
Conclusions
Anodal tDCS over the right DLPFC enhanced the VSA, spatial working memory, and VM
accuracy after the first stimulation and reduced the reaction time of VM after 12
sessions. A long-lasting effect on VSA and VM was found 4 weeks after treatment. This
study corroborated atDCS as a safe technique to improve cognitive function.
Keywords
List of abbreviations:
AD (Alzheimer's disease), atDCS (anodal transcranial direct current stimulation), CANTAB (Cambridge Neuropsychological Test Automated Battery), DLPFC (dorsolateral prefrontal cortex), DMS (delayed matching to sample), MCI (mild cognitive impairment), MoCA (Montreal Cognitive Assessment), PRM (pattern recognition memory), RVP (rapid visual information processing), SWM (spatial working memory), tDCS (transcranial direct current stimulation), TMSE (Thai Mental State Examination), VM (visual memory), VSA (visual sustained attention)To read this article in full you will need to make a payment
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Article Info
Publication History
Published online: May 10, 2020
Footnotes
Supported by the Ratchadapisek Sompoch Endowment Fund, Chulalongkorn University (grant no. RA 58/095 ).
Disclosures: none.
Clinical Trial Registration No.: TCTR20151125002.
Identification
Copyright
© 2020 by the American Congress of Rehabilitation Medicine
