EEG response and productivity outcome under changing indoor environment

TL;DR

This study explores how indoor temperature, noise, and lighting affect productivity and brain activity in young adults.

Contribution

The study provides real-world experimental evidence linking specific indoor environmental conditions to productivity outcomes.

Findings

Higher temperature (23–25 °C) is associated with increased productivity in young adults.

Lower noise levels (45 dB) and moderate lighting (700 lx) are linked to better productivity outcomes.

Males and females respond differently to the same indoor environmental conditions.

Abstract

Indoor environmental quality (IEQ) is a key determinant of health economics and specifically of productivity. In this research, we investigated the effect of three indoor environmental factors (temperature, acoustics, and luminescence) under four different scenarios to generate real-world evidence on how changes in the indoor environment affect productivity-related outcomes.

Two levels of temperature (15–17 °C and 23–25 °C), two levels of acoustics (45 dB and 85 dB), and two levels of luminescence (300 lx and 700 lx) were tested. We recruited 30 undergraduate students and measured their brain activity using electroencephalogram (EEG) to obtain the Concentration Power Index (CPI) and cognitive response with the Grooved Pegboard Test (GPT). Individual’s productivity was measured objectively by the CPI and subjectively by the GPT. Mixed-effects regression analysis indicated that all three indoor environmental factors have statistically significant effects on productivity.

Relatively higher temperature is associated with increased productivity, as indicated by higher CPI under the experimental conditions. Lower acoustics are associated with productivity as indicated by lower GPT under the conditions investigated. Luminescence is inversely associated with productivity, as higher luminescence has a statistically significant correlation with lower GPT within the tested luminescence range. However, males and females responded differently under the same indoor environment. Specifically, relatively lower temperature is associated with higher productivity for females and lower GPT for males. Higher acoustics and lower luminescence are associated with productivity for males.

Overall, the study results suggest that indoor temperature at 23–25 °C, acoustics at 45 dB, and luminescence at 700 lx provide a more favorable and productive environment for young adults. Louder environment and excessive lighting correspond to lower human capital approach (HCA) values and higher temperature corresponds to HCA again. With first-hand experimental results, this study provides real-world indoor environmental data and could provide scientific support for optimizing indoor environments and contributing to the future interior environment design to enhance human productivity.

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