10 Minutes Frontal 40 Hz tACS-Effects on Working Memory Tested by Luck-Vogel Task

Area of Science:

• Cognitive Neuroscience
• Neuroscience
• Electrophysiology

Background:

• Working memory involves maintaining and updating information, with theta and gamma oscillations in the frontoparietal network playing key roles.
• Transcranial alternating current stimulation (tACS) modulates brain oscillations, showing potential in cognitive neuroscience.
• The effects of frontal gamma-tACS on working memory electrophysiology and behavior remain under-investigated.

Purpose of the Study:

• To investigate the impact of frontal gamma-tACS on working memory performance and associated electrophysiological changes.
• To test the hypothesis that 10-minute frontal gamma-tACS enhances working memory outcomes.

Main Methods:

• Forty-one healthy young participants underwent a 10-minute 40 Hz tACS or sham stimulation over the frontal cortex.
• Working memory was assessed using the Luck-Vogel cognitive behavioral task.
• Electroencephalography (EEG) was recorded before and after the intervention to analyze spectral power and coherence.

Main Results:

• Frontal gamma-tACS led to increased power spectral density in high beta and low gamma EEG bands.
• A decrease in left-right coherence was observed following tACS.
• No significant improvements in working memory success rates or response times were detected.

Conclusions:

• A 10-minute frontal 40 Hz tACS protocol was insufficient to yield significant behavioral improvements in working memory.
• Electrophysiological changes in response to tACS were evident, suggesting potential neural modulation.
• Further optimization of tACS parameters, such as duration and intensity, may be necessary to achieve behavioral effects.