Neural Mechanisms Underlying Brain Gamma Entrainment after Periodic Auditory Stimulation at Gamma Frequency

Abstract

External sensory stimuli presented at gamma frequency have been shown to mitigate cognitive symptoms in Alzheimer’s disease. However, the neural mechanisms underlying this therapeutic effect remain elusive. In this study, we investigated the effects of auditory stimulation at gamma frequency on brain oscillations and the role of theta oscillations in the process of entrainment in a group of dementia patients. Our findings indicate that external auditory stimulation at gamma frequency effectively produces gamma entrainment in the brain, and high theta power at rest predicts the level of gamma entrainment. These data suggest that external sensory stimulation modulates brain oscillations by enhancing gamma entrainment, particularly in patients with higher theta power. Our study sheds light on the potential future applications of non-invasive external sensory stimulation at gamma frequency in treating neurodegenerative diseases. However, the mechanisms underlying the generation of theta and gamma oscillations and their interactions are still not fully understood, and further research is needed to investigate these mechanisms and to develop targeted treatments that can enhance cognitive function by modulating brain oscillations. In summary, our study provides valuable insight into the potential therapeutic benefits of gamma frequency stimulation in the treatment of Alzheimer’s disease and highlights the importance of understanding neural oscillations in the brain.