Olfactory VR Shows Promise in Preventing Dementia, Study Finds

What have you done to keep your brain young and healthy? Personally, I've taken a laid-back approach to learning Korean and weight training to combat forgetfulness. However, there's a natural way to boost memory that we often overlook—our sense of smell, which can be enhanced using a VR smell device.

The Proust Effect: From Drama to Scientific Proof

You might have heard of the Proust Effect, which refers to how a specific scent can trigger vivid memories in the brain. Remember the 2023 hit drama "First Love" that captivated audiences in Japan and Taiwan? The lead character regains her lost memories through a sensory journey involving the scent of lilacs, the taste of Neapolitan pasta, sign language, a kiss, and the theme song - this isn't just a rom com.

The lilacs she once smelled as a young girl helped her regain her memory in middle age. (Source: X)

Recently, a team from Tokyo Institute of Technology, University of the Arts London, Bunkyo Gakuin University, and Hosei University published a study in Scientific Reports. They developed a VR game designed to enhance cognitive abilities in people experiencing cognitive decline, based on the scientific fact that stimulating the sense of smell can improve cognition.

Unlike typical VR experiences that focus on sight and sound, this system incorporates a "scent display" using a VR smell device. As users move through a virtual garden, they can actually smell the flowers, which helps activate the brain and improve cognitive function. The results showed that seniors who tried it experienced a boost in their cognitive abilities!

Cognitive abilities refer to the brain's functions for receiving information, learning, thinking, and adapting to the environment, including memory, attention, language expression, spatial interpretation, and logical reasoning. These abilities naturally decline with age, and dementia can accelerate this process.

How Does the VR Game Work? A Three-Stage Brain Training Journey

The research team recruited 30 seniors aged 63 to 90 as "gamers." The game is divided into three stages, each targeting specific cognitive training:

The first stage is "Scent and Memory Activation." When seniors touch a virtual statue, it releases a specific scent and a five-second white mist. This dual sensory stimulation, facilitated by the VR smell device, enhances the brain's memory encoding process.

The second stage is "Finding the Scent Source." Seniors are placed in a virtual garden and must rely on changes in scent intensity and flickering lights to locate the scent source: a stone garden lantern. This stage challenges spatial navigation and scent recognition, testing whether seniors can retain previous scent memories.

The third stage is "Scent Matching." Seniors face three colored clouds emitting different scents and must compare them to select the one that matches the initial target scent. The game uses light cues (green for correct, red for incorrect) to help seniors adjust their strategy, training their scent recognition and memory skills.

This game design goes beyond simply "smelling" by combining multiple sensory stimuli and interactions, allowing the brain to continuously exercise core cognitive abilities like memory, spatial awareness, and reasoning during gameplay.

The game consists of three stages: first, players smell and memorize scents; then, they explore a virtual environment to find the matching aromas. (Source: Science Tokyo)

Meticulously Designed Game Experiment: From Levels to Scent Considerations

The experiment was carefully designed. Each participant played the VR game twice, with a six-day interval to avoid bias from repeated play and training. Before the first game and after the second, participants underwent cognitive tests as a "brain check-up" comparison.

The results showed that after just 20 minutes of VR gameplay, seniors significantly improved their visual-spatial and memory skills! In the "Hiragana Rotation Task," they had to determine if rotated Japanese characters matched the originals, with scores improving from 19-82 to 29-85. In the "Word-Based Spatial Memory Recall Task," they had to remember the positions of words in a grid, with scores rising from 0-15 to 3-15.

As for the scent selection, the research team put in a lot of effort. They used a scent discrimination triangle test to identify two highly distinguishable scent combinations: orange, lavender, spearmint, melon, mango, and plum. Just reading about them makes you want to smell the scents from the device!

Why Use VR for Scent Experiences?

Incorporating scents into VR experiences is nothing new. We've previously introduced a VR wine tasting game that lets you identify wines by their virtual aromas. Scent-based VR experiences can also be used for training sommeliers and perfumers, helping those who lost their sense of smell due to COVID-19, or assisting veterans with mental rehabilitation, offering a novel form of therapy.

"VR provides a promising platform [to simulate sensory states] in a controlled and engaging way," explains Professor Takamichi Nakamoto from Tokyo Institute of Technology. The advantage of VR technology, especially with a VR smell device, is its ability to create immersive experiences that fully engage users while precisely controlling the intensity and timing of sensory stimuli. This controllability is crucial for scientific research and therapeutic applications.

Sometimes, when we return to a familiar place or smell a particular scent, a wave of nostalgia hits us. But now, perhaps we can see it positively: it means your memory is intact, and your brain is working hard. The connection between smell and the brain is like training those small muscle groups during a workout. With the growing accessibility and convenience of VR wearables, scent-based VR experiences could become a fun and healthy hobby for anti-aging in the future.