Temperature Illusions in Mixed Reality using Color and Dynamic Graphics

TL;DR

This study evaluates whether the color-temperature illusion can be recreated in mixed reality (MR) and investigates a novel dynamic-graphics temperature illusion using MR. The authors employ an AR setup with real-temperature anchors and virtual effects (color, fire, ice) to elicit perceived temperature from 30 participants across three blocks. Results show replication of the color-temperature illusion in MR and reveal a stronger, distinct dynamic-graphics-temperature illusion—where fiery and icy graphics influence temperature perception differently from color alone. The findings suggest MR can host potent perceptual illusions through graphical effects, offering new avenues for immersive MR design and inviting further research into the mechanisms behind these effects. Practically, the work points to graphical texture and particle systems as viable tools for modulating user perception without additional haptic hardware.

Abstract

Sensory illusions - where a sensory stimulus causes people to perceive effects that are altered by a different sensory stimulus - have the potential to enrich mixed-reality based interactions. The well-known colour-temperature illusion is a sensory illusion that causes people to, somewhat counterintuitively, perceive blue objects to feel warmer and red objects to feel colder. There is currently little information about whether this illusion can be recreated in mixed reality (MR). Additionally, it is unknown whether dynamic graphical effects made possible by mixed-reality systems could create a similar or potentially stronger effect to the color-temperature illusion. The results of our study (n=30) support that the color-temperature illusion can be recreated in MR and that dynamic graphics can create a new temperature-sensory illusion. Our dynamic-graphics-temperature illusion creates a stronger effect than the color-temperature illusion and has more intuitive relationship between the stimulus and the effect: cold graphical effects (a virtual ice ball) are perceived as colder and hot graphical effects (a virtual fire ball) as hotter. Our results demonstrate that mixed reality has the potential to create novel and stronger temperature-based illusions and encourage further investigation into graphical effects to shape user perception.

Figures (4)

• Figure 1: Top - a virtual ball shown using an augmented reality headset, used as a baseline condition in our study. Lower left - An icy particle and texture effect, which creates the illusion of the object feeling colder. Lower right - A fiery particle and texture effect, which creates the illusion of the object feeling hotter.
• Figure 2: An overview of our multi-block experiment procedure. Each block contains the same structure: an anchoring phase with different temperature pads, and then an interaction with and a temperature estimation of each of the 5 dynamic graphical effects we were testing where the pads were secretly all the same temperature. There were three blocks total, one after the other, along with questionnaires at the beginning and end of the experiment. Brief breaks of a few minutes were allowed between blocks.
• Figure 3: Mean perceived temperatures in Celsius ($\pm$SE) across all experimental blocks.
• Figure 4: Mean perceived temperature (in degrees Celsius; $\pm$SEM) grouped by trial block, demonstrating the change in temperature perceptions throughout the experiment.