Inducing Gamma Oscillations in Healthy Individuals - A pilot study that examines non-invasive treatment for Alzheimer's disease

Abstract

Objective: The aim of the current study was to examine if two different gamma inducing conditions could lead to higher gamma levels in a healthy population of psychology students. Specifically, the study aimed to examine 1) whether it is possible to induce gamma oscillations using either photic stimulation or neurofeedback training in healthy individuals, 2) whether photic stimulation or gamma inducing neurofeedback can lead to lasting changes in the EEG of healthy individuals, and 3) whether one of the two interventions is more effective and can be recommended for future studies. Method: 20 volunteer students were assigned into two groups with 10 participants in each group. Group 1 received photic stimulation and group 2 received neurofeedback training as gamma inducer. The sessions lasted in 20 minutes each and all participants received five sessions in total. A resting EEG was recorded before and after the intervention working as a pre and post-test. Results: The data showed no significant higher gamma levels after intervention in either of the two conditions, and no significant difference between the two groups. Conclusion: The present results indicate that photic stimulation and neurofeedback is not an effective gamma inducer after five sessions, with 20 minutes of exposure. It is necessary with a longer period of exposure to the conditions to show significant improvements in the gamma band for both frequency (Hz) and amplitude (μV). Due to these results, the interventions cannot be recommended for treatment for Alzheimer patients, but it can be recommended to further investigate the effect of gamma inducing protocols in a longer period of time. Optionally, it can be recommended to examine the effect of exposing subjects to several sensory stimuli at the same time.