"Unfocus" on foc.us: commercial tDCS headset impairs working memory.

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• Commercial transcranial direct current stimulation (tDCS) devices, like foc.us, are marketed for cognitive enhancement.
• The prefrontal cortex plays a crucial role in cognitive control processes such as working memory.
• CE-certified tDCS devices have previously shown benefits for working memory.

Purpose of the Study:

• To evaluate the efficacy of the commercial foc.us tDCS headset in improving cognitive performance.
• To investigate the effects of both online and off-line foc.us tDCS on working memory updating and monitoring.

Main Methods:

• A single-blind, sham-controlled, within-subject study design was employed.
• Participants (n=24) were healthy young volunteers.
• The N-back task was used to assess working memory updating and monitoring.

Main Results:

• Active foc.us tDCS, compared to sham stimulation, significantly reduced accuracy in the working memory task.
• This negative effect was observed for both online and off-line stimulation protocols.
• The findings contradict claims of cognitive improvement from the commercial tDCS device.

Conclusions:

• The commercial foc.us tDCS headset did not enhance, but rather impaired, working memory performance in healthy young adults.
• This study underscores the importance of scientific validation for claims made by the brain training industry.
• Rigorous research is essential to verify the effectiveness of neurostimulation devices.