Nonthermal sensory input and altered human thermoregulation: effects of visual information depicting hot or cold environments

The influence of virtual environment on thermal perception: physical reaction and subjective thermal perception on outdoor scenarios in virtual reality

Positive thermal perception can affect users' climate-controlling behavior, indirectly reducing a building's operational carbon emissions. Studies show that some visual elements, such as window sizes and light colors, can influence thermal perception. However, until recently there has been little interest in the interaction of thermal perception and outdoor visual scenarios or natural elements like water or trees, and little quantitative evidence has been found associating visual natural elements and thermal comfort. This experiment explores and quantifies the extent to which visual scenarios outdoors affect thermal perception. The experiment used a double-blind clinical trial. All tests were done in a stable laboratory environment to eliminate temperature changes, and scenarios were shown through a virtual reality (VR) headset. Forty-three participants were divided into three groups randomly, separately watched VR-outdoor scenarios with natural elements, VR-indoor scenarios, and a control scenario of the real laboratory, then finished a subjective questionnaire conducted to evaluate their thermal, environmental, and overall perceptions while their physical data (heart rate, blood pressure, pulse) was real-time recorded. Results show that visual scenarios could significantly influence thermal perception (Cohen's d between groups > 0.8). Significant positive correlations were found between key thermal perception index, thermal comfort, and visual perception indexes including visual comfort, pleasantness, and relaxation (all PCCs ≤ 0.01). Outdoor scenarios, with better visual perception, rank higher average scores (M ± SD = 1.0 ± 0.7) in thermal comfort than indoor groups (average M ± SD = 0.3 ± 1.0) while the physical environment remains unchanged. This connection between thermal and environmental perception can be used in building design. By being visually exposed to pleasing outdoor environments, the positive thermal perception will increase, and thus reduce building energy consumption. Designing positive visual environments with outdoor natural elements is not only a requirement for health but also a feasible path toward a sustainable net-zero future.

Experimental study on the influence of virtual tourism spatial situation on the tourists' temperature comfort in the context of metaverse

The Metaverse is a new application of the internet and social form which integrates a myriad of new technologies. It can not only create a parallel space that is closely connected to the real world while highly independent, but also bring the immersive experience of virtual scenarios without delay. The virtual tourism space situations that integrate realistic visual, audio, and temperature sensations can restore the real tourism environment to the greatest extent, and improve tourists' perception and satisfaction with the experience. The purpose of this experimental lab study is to examine the effects of the virtual tourism audio-visual conditions and environmental temperature on tourists' thermal sensation and temperature comfort. VR equipment and microclimate simulation technology was applied in a 3 × 2 × 2 experimental design (n = 180), simulating the virtual tourism scenarios. Electrocardiogram devices were also employed to assess participants' physiological indicators. Study results suggest that: (1) Virtual tourism spatial situations (environmental temperature and audio-visual conditions) significantly affect participants' thermal sensation and part of the physiological indicators; (2) Virtual tourism spatial situations (environmental temperature and audio-visual conditions) significantly affect participants' temperature comfort; and (3) Physiological responses (indicators) mediate the effect from tourism spatial situations to temperature comfort. The study mainly contributes to the literature about virtual tourism experience and spatial situations under the concept of the Metaverse, as well as provides theoretical and managerial implications for the development of "immersive" virtual tourism scenarios.

The Effect of Correlated Colour Temperature on Physiological, Emotional and Subjective Satisfaction in the Hygiene Area of a Space Station

The hygiene area is one of the most important facilities in a space station. If its environmental lighting is appropriately designed, it can significantly reduce the psychological pressure on astronauts. This study investigates the effect of correlated colour temperature (CCT) on heart rate, galvanic skin response, emotion and satisfaction in the hygiene area of a space station. Forty subjects participated in experiments in a hygiene area simulator with a controlled lighting environment. The lighting conditions included 2700 K, 3300 K, 3600 K, 5000 K and 6300 K; physiological responses (heart rate, galvanic skin response), as well as emotion and satisfaction, were recorded. The results showed that CCT significantly influenced the participants’ physiological and subjective responses in the space station hygiene area. 6300 K led to the best emotion and satisfaction levels, the highest galvanic skin response and the lowest heart rate. The opposite was true for 2700 K.

Temperature-Based Crossmodal Correspondences: Causes and Consequences

The last few years have seen an explosive growth of research interest in the crossmodal correspondences, the sometimes surprising associations that people experience between stimuli, attributes, or perceptual dimensions, such as between auditory pitch and visual size, or elevation. To date, the majority of this research has tended to focus on audiovisual correspondences. However, a variety of crossmodal correspondences have also been demonstrated with tactile stimuli, involving everything from felt shape to texture, and from weight through to temperature. In this review, I take a closer look at temperature-based correspondences. The empirical research not only supports the existence of robust crossmodal correspondences between temperature and colour (as captured by everyday phrases such as 'red hot') but also between temperature and auditory pitch. Importantly, such correspondences have (on occasion) been shown to influence everything from our thermal comfort in coloured environments through to our response to the thermal and chemical warmth associated with stimulation of the chemical senses, as when eating, drinking, and sniffing olfactory stimuli. Temperature-based correspondences are considered in terms of the four main classes of correspondence that have been identified to date, namely statistical, structural, semantic, and affective. The hope is that gaining a better understanding of temperature-based crossmodal correspondences may one day also potentially help in the design of more intuitive sensory-substitution devices, and support the delivery of immersive virtual and augmented reality experiences.

Perceptual-Semantic Congruency Facilitates Semantic Discrimination of Thermal Qualities

The ability to sense temperature is vital to our life. It signals the environmental condition, reflects the physiological conditions of our own body, and generates feelings of pleasantness or unpleasantness. Moreover, recent studies have demonstrated implicit associations between physical temperature and social/emotional concepts, suggesting the processing of temperature may even influence cognition. In this work, we examined the effect of physical warmth and coldness on semantic cognition. Participants performed speeded target categorization for thermal descriptors in the form of semantic words or illustrative figures representing the thermal qualities “warm” or “cold” while physical thermal stimulation was presented. We compared the average reaction time (RT) for the congruent and incongruent conditions managed by response key assignments. In the congruent condition, the response key for the symbol associated with warmth (coldness) was assigned to the hand with warm (cold) thermal stimulation, and in the incongruent condition the key assignment was reversed. Our results demonstrate that the average RT in the congruent condition was faster than in the incongruent one for both forms of thermal descriptors, suggesting that the experience of physical temperature facilitates the internal processing of the meaning of thermal quality.

The Role of Pitch and Tempo in Sound-Temperature Crossmodal Correspondences

We explored the putative existence of crossmodal correspondences between sound attributes and beverage temperature. An online pre-study was conducted first, in order to determine whether people would associate the auditory parameters of pitch and tempo with different imagined beverage temperatures. The same melody was manipulated to create a matrix of 25 variants with five different levels of both pitch and tempo. The participants were instructed to imagine consuming hot, room-temperature, or cold water, then to choose the melody that best matched the imagined drinking experience. The results revealed that imagining drinking cold water was associated with a significantly higher pitch than drinking both room-temperature and hot water, and with significantly faster tempo than room-temperature water. Next, the online study was replicated with participants in the lab tasting samples of hot, room-temperature, and cold water while choosing a melody that best matched the actual tasting experience. The results confirmed that, compared to room-temperature and hot water, the experience of cold water was associated with both significantly higher pitch and fast tempo. Possible mechanisms and potential applications of these results are discussed.