By: Prof. Amir Amedi, co-founder and chief scientific officer, Remepy, and director of the Ivcher Institute for Brain, Cognition and Technology, Reichman University
Highlights
- Following a multi-sensory digital treatment protocol that involves multisensory sensory integration, sensory substitution, and sensory masking (blindfolding), participants significantly improved their performance on spatial memory tasks.
- Resting-state Functional MRI analysis revealed improved spatial performance correlated with enhanced connectivity between brain regions responsible for memory, executive frontal areas, and default mode network (DMN) regions.
- The digital treatment protocol may represent a promising approach for mitigating some of the effects of age-related cognitive decline.
- This approach has the potential to enhance healthier aging and longevity, by improving brain connectivity in both healthy subjects and in patients suffering from mild cognitive impairments (MCI) and Alzheimer’s Disease (AD).
The human brain, from the moment a person is born and through later ages, possesses the characteristic of neuroplasticity, which endows the capacity for adaptation and change. A groundbreaking study, recently published in the scientific journal iScience from CELL press by Reichman University scientists, reveals a way to harness this ability to potentially improve brain health across the lifespan. Using an innovative mobile application developed by Remepy Inc., aging adults experiencing subjective cognitive decline (SCD) enhanced their navigational knowledge, which includes spatial navigation and spatial memory skills.
Navigational knowledge is known to decline in both normal and pathological aging, as observed in conditions like MCI, dementia, AD, and Parkinson's disease. Age-related alterations in spatial navigation performance have been identified as a potential indicator, or even a biomarker, for assessing the risk of clinical progression in age-related degenerative diseases. Interestingly, the processing and connectivity of certain brain areas, the Hippocampus and medial temporal cortex, were shown to be involved not only with spatial memory (e.g., Discoveries by O'Keefe & Moser awarded the 2014 Nobel Prize in Physiology or Medicine), but also support verbal and episodic memory. Therefore, an enhancement of navigational knowledge has the potential to delay neurodegenerative processes within the aging brain, and even to mitigate them.
The study included seventeen participants aged 55-60 experiencing SCD, who underwent two weeks of a 30-minute digital daily treatment protocol. The treatment focused on training within a virtual maze, integrating both allocentric (map-based) and egocentric (self-referenced) navigation strategies. Additional elements included progressively increasing maze complexity, as well as sensory substitution and sensory masking: initially navigating using full vision combined with sound, then decreasing the vision input (by partially covering the maze digital environment), and eventually substituting vision with sound only (using complete blindfolding). This use of sensory substitution and sensory masking builds on past research led by the author, which demonstrated that visual deprivation by way of blindfolding or tasks performed through alternate sensory routes, in essence, is a method of freeing the brain to other tasks, while strengthening normally dormant, weak, or inhibited connections and networks.
Following a two-week period of daily training, participants demonstrated a significant improvement in their performance on spatial memory tasks. This enhancement was particularly pronounced during blindfolded navigation segments, highlighting the effectiveness of the multisensory visual-sound approach. Further analysis using functional magnetic resonance imaging (fMRI) revealed a strengthening of synaptic connectivity as recorded by resting state functional connectivity measures within and between brain regions responsible for memory, executive frontal areas, and DMN regions. These areas are the most affected by normal aging – showing weakening of the connectivity pattern with aging and even more weakening of functional connectivity in brain degeneration conditions – so the current approach can potentially help slow down or even reverse this reduced connectivity pattern. The study also shows some individual variability and correlation, highlighting the fact that subjects who improved more in their spatial memory training showed even stronger improvement to their connectivity pattern – as presented in the attached graph (which was included in the graphical abstract published online in iSience Dcember 2024 edition).
These findings suggest that the digital training program may represent a promising approach for enhancing spatial memory and navigation in individuals with SCD (and memory in general), potentially mitigating the effects of age-related cognitive decline. The observed improvements in brain connectivity indicate that the program induced neuroplasticity and enhanced the brain's functional organization to facilitate better spatial cognitive performance. These discoveries might be another step in the journey to mitigate and delay neurodegenerative processes in the aging brain.
