Trigeminal-Based Temperature Illusions

Jas Brooks, Steven Nagels, and Pedro Lopes. 2020. “Trigeminal-based Temperature Illusions.” In Proceedings of the 2020 CHI Conference on Human Factors in Computing Systems (CHI ’20). Association for Computing Machinery, New York, NY, USA, 1–12. DOI:10.1145/3313831.3376806

Received a CHI Best Paper Award (top 1%).


We explore a temperature illusion that uses low-powered electronics and enables the miniaturization of simple warm and cool sensations. Our illusion relies on the properties of certain scents, such as the coolness of mint or hotness of peppers. These odors trigger not only the olfactory bulb, but also the nose’s trigeminal nerve, which has receptors that respond to both temperature and chemicals. To exploit this, we engineered a wearable device based on micropumps and an atomizer that emits up to three custom-made “thermal” scents directly to the user’s nose. Breathing in these scents causes the user to feel warmer or cooler. We demonstrate how our device renders warmth and cooling sensations in virtual experiences. In our first study, we evaluated six candidate “thermal” scents. We found two hot-cold pairs, with one pair being less identifiable by odor. In our second study, pParticipants rated VR experiences with our device trigeminal stimulants as significantly warmer or cooler than the baseline conditions. Lastly, we believe this offers an alternative to existing thermal feedback devices, which unfortunately rely on power-hungry heat-lamps or Peltier-elements.

Paper | Video | GitHub Repo


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Perscovitz, David. “Digital synesthesia: Tricking your brain into experiencing smell as temperature in virtual reality.” Boing Boing, June 26, 2020.

“VR experiences with temperature illusion.” Aneddotica Magazine, June 26, 2020.

“Creating Temperature Illusions Using Smell In Virtual Reality.” Geekologie, June 26, 2020.

Baker, Harry. “University Project Shows Hot And Cold Temperature Change VR Research.” UploadVR, May 24, 2020.

“Uchicago CS Receives Several Awards, Presents Virtual Papers at CHI 2020.” University of Chicago Computer Science, May 08, 2020.

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