The role of post-learning EEG theta/beta ratio in long-term navigation performance

Memory consolidation processes have been shown to benefit from modulations in brain activity, particularly theta oscillations. Our previous studies showed that increases in post-learning Theta/Beta power ratio improves subsequent performance in both procedural and declarative memory across various tasks. In this study, we investigated the role of increases in frontal-midline Theta/Beta power ratio using EEG neurofeedback (NFB) in enhancing spatial memory consolidation during a navigation task in a virtual Minecraft environment. Sixty-four participants were randomly assigned to one of three groups: Theta/Beta NFB, Beta/Theta NFB, or a passive control group. Following spatial memory acquisition and three memory tests in the virtual environment, participants underwent a neurofeedback intervention designed to either upregulating or downregulate the Theta/Beta power ratio. Performance was assessed immediately post-intervention, 24 h later, and one week after the intervention. Results indicate that while some participants failed to regulate their Theta/Beta power by using the NFB display, those who increased their Theta/Beta power ratio, regardless of NFB, showed improved spatial memory, reflected in faster task completion times. Conversely, participants who exhibited a decrease in Theta/Beta ratio showed performance declines, while the passive control group showed minimal improvement. Although all participants improved over time, participants who increased Theta/Beta ratio showed the most substantial gains. These findings highlight the importance of post-learning Theta/Beta ratio oscillations in spatial memory consolidation. The study's implications extend to clinical neuromodulation applications and a deeper understanding of memory processes.