High-Definition Transcranial Direct Current Stimulation (HD-tDCS) enhances working memory training.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neuromodulation

Background:

• Noninvasive brain stimulation, specifically High-Definition transcranial direct current stimulation (HD-tDCS), shows promise for enhancing cognitive functions like working memory (WM).
• Existing research primarily focuses on the direct effects of stimulation, with less attention paid to the interplay between stimulation, training processes, and underlying neural mechanisms.

Purpose of the Study:

• To investigate the impact of different HD-tDCS conditions (active vs. sham) applied to the left dorsolateral prefrontal cortex (LDLPFC) on working memory (WM) training.
• To explore the physiological brain changes associated with HD-tDCS during WM training using electroencephalography (EEG).

Main Methods:

• Twenty participants underwent working memory (WM) training with either active or sham HD-tDCS targeting the left dorsolateral prefrontal cortex (LDLPFC).
• Behavioral performance and electroencephalography (EEG) data were collected to assess training effects and neural activity, specifically changes in alpha (α) and beta (β) band oscillations.

Main Results:

• HD-tDCS significantly improved working memory (WM) training outcomes, particularly during the later stages of training.
• Participants receiving active HD-tDCS exhibited a reduction in time-dependent desynchronization (ERD) in the alpha (α) and beta (β) bands, unlike the sham group where ERD increased.
• EEG data indicated that HD-tDCS altered neural rhythms during WM training.

Conclusions:

• HD-tDCS can accelerate working memory (WM) training, suggesting it can shorten the required training duration.
• The technique modifies neural oscillatory patterns, specifically affecting alpha (α) and beta (β) band activity.
• HD-tDCS holds potential as a therapeutic intervention for individuals with brain injuries, possibly aiding in cognitive rehabilitation.