Investigating if Working Memory Load Modulates the Effects of Visual Stimuly on Thermal Perception and Regulation

Thermal perception is an important factor affecting both the performance [1, 2] and the well-being [3]. Furthermore, maintaining thermal comfort indoors is a major contributor to energy consumption. Heating, Ventilation, and Air Conditioning systems contribute one fifth to the total national energy in developed countries [4]. Therefore, manipulating thermal sensation and comfort is an important factor for reducing energy consumption and creating a pleasant environment.

Previous research showed that thermal perception and physiological thermal regulation are not only influenced by the temperature of the environment but also by visual stimuli [5, 6, 7, 8, 9]. For example, color temperature affects the thermal perception of humans, with colors more shifted to red showing a warmer thermal comfort and sensation, while colors more shifted to blue have the opposite effect [5, 6, 7]. There is also evidence that these colors induce physiological responses [5, 6]. Furthermore, Takakura et al. hypothesized that not only color temperature but also the design of the environment influences thermal perception and physiological responses by conditioning [8, 9]. These effects have also been recreated using VR environments [10, 11], indicating that these effects could be utilized in a private and work environment through the use of virtual reality.

Research also showed that working memory load and attention can modulate perception across multiple modalities. For instance, it has been demonstrated that a higher memory load reduced taste sensitivity [12, 13] and the perception of thermal-induced pain [14]. It is, however, unclear if working memory load and attention also influence the effects of visual stimuli on thermal perception. This interaction could play a relevant role in utilizing these effects in workplace environments and in designing gaming tasks.

The aim of this thesis is to investigate how working memory load and attention affect the alteration of thermal perception and body temperature by visual stimuli. We therefore plan to conduct two studies. In the first study, subjects will be exposed to an environment with warm visual stimuli and an environment with cold visual stimuli. During exposure to the environments, participants will be idle, presented with stimuli for an n-back task, and solving an n-back task. During every condition, thermal comfort, thermal sensation, and body temperature will be measured. Additionally, room temperature, humidity, and presence in the virtual environment will be measured as possible confounders. The study will be conducted as a lab study with a within-subjects design counterbalanced using a Latin square design.

Depending on the results of the first study, we want to conduct a second study to further investigate these findings. If we find an effect of working memory load on the alteration of thermal perception by visual stimuli, we will further explore this modulation by presenting n-back tasks with varying difficulties in the environments. If we find no effect, we want to test tasks with higher ecological validity by presenting more realistic, real-world tasks.

• Researching related work
• Implementing virtual environments with tasks
• Designing the studies
• Conducting the studies
• Analyzing the data
• Writing the thesis

• Developing games for VR in Unity
• Empirical study design

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• [2] Zarghami, E., Yazdanfar, S. A., Yekta, N. H., & Dadras, F. (2022). Effect of Environmental Temperature on Working Memory in Military Personnel. Journal of Archives in Military Medicine, 10(3). https://doi.org/10.5812/jamm-128528
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• [9] Takakura, J. Y., Nishimura, T., & Watanuki, S. (2013). Visual information without thermal energy may induce thermoregulatory-like cardiovascular responses. Journal of physiological anthropology, 32, 1-10. https://doi.org/10.1186/1880-6805-32-26
• [10] Kocur, M., Jackermeier, L., Schwind, V., & Henze, N. (2023, April). The Effects of Avatar and Environment on Thermal Perception and Skin Temperature in Virtual Reality. In Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems (pp. 1-15). https://doi.org/10.1145/3544548.3580668
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• [13] van der Wal, R. C., & van Dillen, L. F. (2013). Leaving a flat taste in your mouth: task load reduces taste perception. Psychological science, 24(7), 1277-1284. https://doi.org/10.1177/0956797612471953
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