A new innovative strategy to improve memory without the use of drugs or surgical procedures combines virtual reality, non-invasive brain stimulation and brain imaging. This technique, successfully developed at EPFL and published in the journal Science Advances, was primarily designed to support elderly people with dementia. It aims to make daily life easier by helping reduce difficulties in remembering practical information such as the location of keys or where the car was parked. The new methodology focuses in particular on spatial memory and has seen the collaboration of three EPFL laboratories, with experiments conducted at the Campus Biotech in Geneva.

During the tests, the researchers used a technique known as Transcranial Electrical Stimulation with Temporal Interference (TTIS). This procedure involves attaching four electrodes to the heads of healthy subjects, and sending painless electrical pulses that target the hippocampus, a part of the brain that is crucial for organizing spatial memory. The participants were then given virtual reality headsets that immersed them in a simulated environment where they had to navigate and memorize various landmarks.

The virtual environment was chosen by the scientists to precisely assess the ability to remember spatial information. The results showed a clear improvement in the participants' recall times, or the time it takes to navigate to a specific object. Elena Beanato, co-author of the study with Friedhelm Hummel, said that stimulating the hippocampus led to a temporary increase in brain plasticity. When combined with training in a virtual context, this plasticity appears to contribute to improved spatial navigation.

Functional magnetic resonance imaging was also used during the experiment to monitor brain activity in real time. This allowed changes in neural activity to be observed that were linked to the behaviors of individuals, providing a deeper understanding of how non-invasive stimulation affects cognitive functions. Olaf Blanke, another author of the research, suggested that in the future this approach could be used to develop specific therapies for patients with cognitive difficulties, presenting a non-invasive method to improve memory and spatial skills.