Turning up the heat: The impact of indoor temperature on selected cognitive processes and the validity of self-report

Indoor climate interventions are often motivated from a worker comfort and productivity perspective. However, the relationship between indoor climate and human performance remains unclear. We assess the effect of indoor climate factors on human performance, focusing on the impact of indoor temperature on decision processes. Specifically, we expect heat to negatively influence higher cognitive rational processes, forcing people to rely more on intuitive shortcuts. In a laboratory setting, participants (N=257) were exposed to a controlled physical environment with either a hot temperature (28° C) or a neutral temperature (22° C) over a two-hour period, in which a battery of validated tests were conducted. We find that heat exposure did not lead to a difference in decision quality. We did find evidence for a strong gender difference in self-report, such that only men expect that high temperature leads to a significant decline in performance, which does in fact not materialize. These results cast doubt on the validity of self-report as a proxy for performance under different indoor climate conditions.