As the world’s population is aging, supporting the elderly in maintaining their cognitive and memory functions has become an urgent concern. The United Nations estimated that in the 2070s, there were more than 2.2 billion people aged 65 or over, exceeding the world number of children under the age of 18. This demographic change is particularly declared in Japan, the fastest country, where 28.7% of the population is 65 years or more.
A promising strategy for countering cognitive decline is through olfactory stimulation-binding smell. The signals of the smell go directly to the regions of the brain involved in memory and emotion. Based on this knowledge, a joint research team from the Institute of Science Tokyo (Science Tokyo), the University of London Arts, Bunkyo Gakuin University and Hosei University, Japan, developed the first method of cognitive training in the world for the elderly by combining olfactory stimulation with virtual reality (VR). The study was published in volume 15 of the journal Scientific relationships March 28, 2025.
VR provides a promising platform to simulate sensory conditions in a controlled but engaging way. By combining objectives focused on real -time feedback, our VR olfactory training approach can increase cognitive engagement and maximize its therapeutic impact. “”
Professeur Takamichi Nakamoto de Science Tokyo
The method implies an olfactory display which emits specific perfumes during the immersive VR gameplay, activating the brain regions linked to memory and emotions. In activity, participants are invited to memorize and later match perfumes in a virtual environment. The experience begins in a virtual landscape. Using a VR controller, participants interact with a source of perfume represented by a stone statue. When touched, the statue releases a specific fragrance, accompanied by a cloud of white steam as a visual mark to strengthen memory.
-Participants then explore the virtual landscape to locate a source of perfume. As they move in the landscape, the olfactory display emits subtle traces of the odor to guide them towards the location. By reaching the source of odor, represented as a stone lantern, they meet three colorful vapor clouds, each emitting a different fragrance. Their task is to compare odors and identify that which corresponds to the original scent they have memorized.
“The odor memory phase reinforces the recognition of odors and the coding of memory by linking the olfactory stimulus with a visual landmark. The navigation phase challenges players to integrate spatial navigation into the recognition of odors while retaining the memory of the initial recovery. The comparison of the final odors initiates olfactory discrimination and the recovery of working memory.
The activity has led to notable cognitive improvements in 30 elderly people aged 63 to 90 years. After only 20 minutes of VR play, participants showed improvements in visuospatial rotation and memory. Visuospatial treatment and cognitive function have been evaluated by different tasks. In Hiragana’s rotation task, where they were to decide whether the Japanese shot characters corresponded to the original, the scores went from 19 to 82 to 29–85. In a space memory reminder task based on words, where participants memorized the positions of words in a grid, the scores went from 0 to 15 to 3 to 15. These improvements were validated by statistical analysis.
With continuous research and development to more affordable olfactory displays or alternative perfume delivery methods, OLFACTIVE VR activities could become an accessible and engaging tool to support mental health in the elderly.
