Lotuscent: Targeted memory reactivation for wellbeing using scent and VR biofeedback

Judith Amores

The lotus flower is an ancient symbol that has been associated with spiritual awakening or enlightenment.

In yoga and meditation, the lotus flower has been used as a symbolic support for the mind. The heart can be visualized as a lotus flower unfolding at the center of the chest. In Egyptian mythology, Nefertem was the lotus god of healing and perfume. Inspired by these mythologies, symbols, and practices, we created Lotuscent.

Lotuscent is a smartphone-controlled scent delivery device that can be used day and night. It is temporally precise (the fastest we have found, going down to microseconds) and silent enough to be used during meditation or sleeping. It is capable of releasing scent based on a person's physiological state and physical location (e.g, it can detect if the person is at home or at work). 

Inspired by a focused meditation practice where the heart can be visualized as a lotus flower opening inside the chest and subtly spreading its petals with each breath, we coupled Lotuscent to a biofeedback VR experience that maps meditative brain activity to the opening of a digital flower while also releasing scent. Our vision is to ease and guide the meditation practice while at the same time creating an association in the person's mind between the scent and the meditative state. The same scent can then be reactivated throughout the day and night. Our goal is to create a system that can help a person be more mindful, reduce stress and anxiety, and improve sleep quality. 

Our motivation

Stress, anxiety, insomnia, and low quality of sleep are growing problems in society, partially due to our stressful modern lifestyles. An estimated 70 million Americans suffer from sleep disorders. Sleep insufficiency and bad quality of sleep are correlated with an increased risk of anxiety, diabetes, heart disease, stroke, obesity, and high blood pressure. 40 percent of the people that look for medical assistance regarding sleep problems have a psychiatric disorder and more than 70 percent of patients with depression have insomnia. 

This is raising the need for portable, at-home devices that can help increase people's sleep quality and wellbeing (the revenue of sleeping aids was $69.5 billion in 2017 and is projected to be $101.9 billion by 2023). Although an increasing number of products that aim to quantify sleep and physical activity are available in the market, most efforts have gone towards improving sleep tracking accuracy instead of developing solutions for improving sleep quality. In addition, most of the current devices are limited to display-based interfaces on smartphones or watches that show diagrams and tips to improve lifestyle. However, little research and development have gone into developing solutions that aim to interact with people in a more subtle manner to improve their wellbeing. Part of the problem may well be that our technologies are mainly focused on audio and visual feedback. In contrast, the sense of smell differs from other forms of perception by being closely tied to the emotional center of the brain. The olfactory bulb has direct connections to the two brain areas that are responsible for processing and controlling emotions and memories. Unlike other modalities, scents can be presented during sleep and have a measurable effect on sleep and dreams without awakening the subject [1,2]. Previous scientific research has shown how odors can modulate mood, cognition and behavior to reduce stress and improve sleep quality. Unfortunately, current scent technologies used in sleep laboratories are not portable and require the use of nasal masks and large olfactometers that cost up to $100K.  

This is why we created Lotuscent

We believe using scent during sleep represents an interesting way of improving sleep quality and a means of interacting with the sleeper without disturbing them. While traditional user interfaces have focused on visual, audio or haptic modalities, both olfactory and sleep interfaces are still in their infancy. We hope to change this with the introduction of the Lotuscent device.


  1. What is the current stage of the project?

    Lotuscent is an early prototype that has been tested for technical functioning. We are looking forward to run studies with human subjects in the following months.

  2. What is targeted memory reactivation?

    Targeted Memory Reactivation (TMR) is a technique that  uses a stimuli like sound or a smell associated with prior learning to enhance the memory-strengthening processes that happen during sleep. 

  3. Why scent?

    Unlike sound or light, releasing a smell while sleeping is not likely to wake you up. Previous work has shown how certain types of odors do not lead to arousals during sleep, but they are still processed by the brain:

    [1] Carskadon, Mary A., and Rachel S. Herz. "Minimal olfactory perception during sleep: why odor alarms will not work for humans." Sleep 27.3 (2004): 402-405.

    [2] Stuck, Boris A., et al. "Arousal responses to olfactory or trigeminal stimulation during sleep." Sleep 30.4 (2007): 506-510.APA


Best Demonstration Award:

An IEEE EMBS Symposium and Workshop: Brain, Mind, and Body: Cognitive Neuroengineering for Health and Wellness

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