The Role of Balanced Excitatory and Inhibitory Neurons in Brain Memory Processing

Recent research from the Friedrich Miescher Institute has shed light on how the brain organizes and processes memories through a delicate balance of excitatory and inhibitory neurons. A study published in the journal eLife demonstrates that these neural interactions play a crucial role in maintaining both stability and flexibility within neural networks involved in memory storage.

Traditionally, it was believed that memory networks depend on stable activity patterns to encode information. However, findings from this study suggest that certain brain regions operate more dynamically than previously thought, utilizing a finely tuned balance between excitatory neurons—which promote neural activity—and inhibitory neurons—which suppress it—forming what are known as E/I assemblies. These assemblies are vital for the brain to both store memories effectively and adapt to new information.

To explore this, scientists developed a computational model based on activity observed in a zebrafish brain region involved in odor memory. This region is comparable to mammalian areas responsible for constructing abstract mental maps. Unlike earlier models, which lacked precise equilibrium, this new approach accurately simulated how real neural circuits manage activity that initially appears random but ultimately becomes stable and reliable.

"By adjusting the E/I balance, we can create a neural network that is both adaptable and resilient," explains Friedemann Zenke, a lead researcher at FMI. The team discovered that networks with well-balanced E/I interactions performed better in classifying odors and exhibited enhanced stability when new memories were added. These findings indicate that E/I assemblies are essential not only for memory stabilization but also for the process of learning.

Furthermore, the research indicates that maintaining this balance allows neural networks to handle overlapping memories without losing stability. This robustness suggests that similar principles might be at work in various brain regions involved in memory and learning, opening pathways for future studies on neural plasticity and cognitive functions.

This breakthrough enhances our understanding of how sensory information is processed and stored, highlighting the importance of neural balance in cognitive health and disease. Future research will aim to explore how these principles apply across different brain areas and their potential implications for neurodegenerative conditions and learning disabilities.

Source: https://medicalxpress.com/news/2025-05-excitatory-inhibitory-neurons-brain-networks.html