Anodal high-definition transcranial direct current stimulation reduces heart rate and modulates heart-rate variability in healthy young people: A randomized cross-controlled trial

Area of Science:

• Neuroscience
• Cardiovascular Physiology
• Non-invasive Brain Stimulation

Background:

• The dorsolateral pre-frontal cortex (DLPFC) plays a role in autonomic nervous system regulation.
• Heart rate (HR) and heart-rate variability (HRV) are key indicators of autonomic function.
• High-definition transcranial current stimulation (HD-tDCS) is a non-invasive brain stimulation technique.

Purpose of the Study:

• To investigate the effects of anodal HD-tDCS over the left DLPFC on HR and HRV in healthy young individuals.
• To determine if left DLPFC stimulation can modulate sympathetic and parasympathetic nervous system activity.

Main Methods:

• A randomized crossover trial involving 40 healthy young participants.
• Participants received either anodal HD-tDCS or sham HD-tDCS over the left DLPFC, with a 1-week washout period.
• Electrocardiogram (ECG) data were recorded continuously to measure HR and HRV parameters.

Main Results:

• Anodal HD-tDCS over the left DLPFC significantly decreased HR compared to sham stimulation and baseline.
• Significant increases in average normal-to-normal intervals (AVG NN), low-frequency (LF) power, total power (TP), and the LF/HF ratio were observed.
• Sham HD-tDCS showed no significant effects on HR or HRV.

Conclusions:

• Anodal HD-tDCS applied to the left DLPFC effectively reduces HR and modulates HRV in healthy young adults.
• HD-tDCS demonstrates potential for the acute modulation of cardiovascular function.
• This technique may offer a novel approach for influencing autonomic nervous system activity.