Experiments show we recognize imperceivable dualities and opposites, such as blue versus hot and red versus cold. We identify more closely with a hot blue object than a hot red one and a cold red object more than a cold blue one.
The hue heat hypothesis demonstrates how we consider certain qualities to be opposites even though we shouldn’t think of them as opposites based on experience, and how it can influence our behavior:
“The Hue Heat Hypothesis (HHH) is based on the idea that light and colours of the environment can affect thermal perception and influence thermal comfort. Specifically, it states that, when spectral power distribution of light reaching an observer’s eye is characterized by long wavelengths in the visible spectrum, the space is perceived as warmer; conversely, when small wavelengths are predominant, the space is perceived as cooler (Bellia et al. (2019).”
Experiments show people will hold a hot blue vessel longer than a hot red one and a cold red vessel longer than a cold blue one (Ziat et al. 2016). Blue coloration perceptually counteracts or moderates heat, and red counteracts coldness, meaning hot and blue are opposites in the mind, or psychothermal opposites, as predicted based on semantic and other evidence in More and Less Exciting Things and Categories of the Mind. We know hot and dark and cold and bright to be dualistic opposites even though we wouldn’t learn this from normal experience. In our experience it’s not true in any absolute sense that blue and hot or red and cold are opposites. It’s only true in the mind and the substance of the brain.
It might be argued based on hue heat experiments that a bright hot object is generally more exciting than a hot dark or cold bright object, which themselves are more exciting than a cold dark one. Hot dark and cold bright objects, the ones we hold longer on average, at least in a simple, contact time or latency based sense, are more likable or familiar than cold dark or hot bright ones.
The results of hue heat experiments reflect sensory biases favoring the mixtures hot — dark and bright — cold over the perceptual combinations hot — bright and cold — dark. Adding blue to heat or heat to blue creates a perceptual mixture with a sort of moderation, familiarity and amusing complexity that red heat and blue coldness do not convey. It’s also been found that red light decreases cold pain thresholds and increases the perceived loudness of louder sounds, or increases sensitivity to higher temperature and sound volume (Landgrebe et al. 2008), and that people feel warmer observing orange than blue (Matsubara 2004, Chinazzo et al. 2017) and in yellow light than blue light (Albers et al. 2015):
“Subjects tend to have slightly warmer thermal sensations in yellow light and slightly colder sensations in blue light.”
Studies show we associate the colors red, orange and yellow with each other in a category which is, in a thermal sense, opposite to darker colors like blue and black. A simple potential explanation for the hue heat effect is that red and yellow light excite and therefore heat the visual sensory system and brain slightly more than blue light. Assuming that this heat corresponds to some extent with psychological excitement in animals might help explain the widespread use of red, yellow and orange coloration for warning purposes, courtship signals and sex organs. Some hue heat experiments have failed to find a significant effect (Bennett et al. 1972).
Darker colors like blue are universally related to sadness and coldness while redder colors look hotter, happier and more provocative, as Clarke and Costall confirmed (2008):
“Consistent with the claim by Levy (1984) that cool colors sedate and warm colors provoke active feelings; the present study also found that ‘warm’ colors such as red, orange, and yellow did evoke the more active emotions (by ‘active emotions’ I refer to Levy’s (1984) use of this term when speaking of emotions or feelings that involve physical arousal, and by the use of ‘passive’ those that sedate).”
Thinking of heat and brightness having similar psychophysical consequences, on the arousing side, and that cold and darkness are physically and emotionally more sedative or related to less psychological excitement suggests that mixtures of other qualities on opposite sides of an emotional continuum can serve to ameliorate each other’s input to make a perceptual object more tolerable and likable.
Albers, Frank, Julia Maier, and Claudia Marggraf-Micheel. “In search of evidence for the hue-heat hypothesis in the aircraft cabin.” Lighting Research & Technology 47.4 (2015): 483–494.
Bellia, Laura, et al. “Dynamic Simulation of a Lighting System Based on the Hue-Heat Hypothesis.” Proceedings of the 16th IBPSA Conference (2019): 2434–2441.
Bennett, Corwin A., and Paule Rey. “What’s so hot about red?.” Human Factors 14.2 (1972): 149–154.
Chinazzo, Giorgia, et al. The effect of short exposure to coloured light on thermal perception: A study using Virtual Reality. No. CONF. 2017.
Clarke, Tom, and Alan Costall. “The emotional connotations of color: A qualitative investigation.” Color Research & Application: Endorsed by Inter‐Society Color Council, The Colour Group (Great Britain), Canadian Society for Color, Color Science Association of Japan, Dutch Society for the Study of Color, The Swedish Colour Centre Foundation, Colour Society of Australia, Centre Français de la Couleur33.5 (2008): 406–410.
Landgrebe, Michael et al. “Effects of colour exposure on auditory and somatosensory perception — hints for cross-modal plasticity.” Neuro endocrinology letters vol. 29,4 (2008): 518–21. https://www.nel.edu/userfiles/articlesnew/NEL290408A12.pdf.
Levy, Bernard I. “Research into the psychological meaning of color.” American Journal of Art Therapy (1984).
Matsubara, Naoki, Akira Gassho, and Yoshihito Kurazumi. “Facilitatory effects of environmental sounds on hue-heat phenomena.” 18th Int. Congr. Acoust. Vol. 2. 2004.
Ziat, Mounia, et al. “A Century Later, the Hue-Heat Hypothesis: Does Color Truly Affect Temperature Perception?” Haptics: Perception, Devices, Control, and Applications Lecture Notes in Computer Science, 2016, pp. 273–280., doi:10.1007/978–3–319–42321–0_25.