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Changes in EEG signals during the cognitive activity at varying air temperature and relative humidity

Abstract

In this study, we examined changes in EEG signals during the cognitive activity at different air temperatures and relative humidities (RH). Thirty-two healthy young people acclimatized to the subtropical climate of Changsha, China, were recruited as subjects. They experienced four air temperature levels (26, 30, 33, and 37 °C) and two relative humidity levels (50 and 70%) in a climate chamber. During 175 min-long exposures to each thermal condition, they performed cognitive tasks and their EEG signals were measured. Relative humidity of 70% and increased temperature at this relative humidity significantly increased the relative power of δ-band and significantly decreased relative power of θ-band, α-band, and β-band. This may suggest that subjects were more sleepy but less drowsy, and it was more difficult for them to think clearly. At the same time, subjective evaluations indicated that they could be less alert and it was harder for them to think. However, no changes in performance of tasks measuring cognitive abilities were observed. It remains therefore unclear whether EEG can be a credible marker of changes in cognitive activity as a result of changes in indoor environmental quality in buildings and the future experiments should closely examine this issue.

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References

  1. Niedermeyer E, da Silva FL, editors. Electroencephalography: basic principles, clinical applications, and related fields. Lippincott Williams & Wilkins: Philadelphia, PA, USA, 2005.

  2. Shan X, Yang EH, Zhou J, Chang VWC. Human-building interaction under various indoor temperatures through neural-signal electroencephalogram (EEG) methods. Build Environ. 2018;129:46–53.

    Article  Google Scholar 

  3. He Manchen, Lian Zhiwei, Chen Pin. Evaluation on the performance of quilts based on young people’s sleep quality and thermal comfort in winter. Energy Build. 2019;183:174–83.

    Article  Google Scholar 

  4. Herrmann CS, Strüber D, Helfrich RF, Engel AK. EEG oscillations: from correlation to causality. Int J Psychophysiol. 2016;103:12–21.

    Article  Google Scholar 

  5. Becerra LR, Breiter HC, Stojanovic M, Fishman S, Edwards A, Comite A, et al. Human brain activation under controlled thermal stimulation and habituation to noxious heat: an fMRI study. Magn Reson Med: Off J Int Soc Magn Reson Med. 1999;41:1044–57.

    Article  CAS  Google Scholar 

  6. Craig AD, Chen K, Bandy D, Reiman EM. Thermosensory activation of insular cortex. Nat Neurosci. 2000;3:184–90.

    Article  CAS  Google Scholar 

  7. Davis KD, Kwan CL, Crawley AP, Mikulis DJ. Functional MRI study of thalamic and cortical activations evoked by cutaneous heat, cold, and tactile stimuli. J Neurophysiol. 1998;80:1533–46.

    Article  CAS  Google Scholar 

  8. Lv B, Su C, Yang L, Wu T. Effects of stimulus mode and ambient temperature on cerebral responses to local thermal stimulation: An EEG study. Int J Psychophysiol. 2017;113:17–22.

    Article  Google Scholar 

  9. Yao Y, Lian Z, Liu W, Shen Q. Experimental study on physiological responses and thermal comfort under various ambient temperatures. Physiol Behav. 2008;93:310–21.

    Article  CAS  Google Scholar 

  10. Lan L, Wargocki P, Wyon DP, Lian Z. Effects of thermal discomfort in an office on perceived air quality, SBS symptoms, physiological responses, and human performance. Indoor Air. 2011;21:376–90.

    Article  CAS  Google Scholar 

  11. Wargocki P, Wyon DP. The effects of moderately raised classroom temperatures and classroom ventilation rate on the performance of schoolwork by children (RP-1257). Hvac&R Res. 2007;13:193–220.

    Article  Google Scholar 

  12. Fang L, Wyon DP, Clausen G, Fanger PO. Impact of indoor air temperature and humidity in an office on perceived air quality, SBS symptoms and performance. Indoor Air. 2004;14:74–81.

    Article  Google Scholar 

  13. Wang H, Olesen BW, Kazanci OB. Using thermostats for indoor climate control in offices: the effect on thermal comfort and heating/cooling energy use. Energy Build. 2019;188–189:71–83.

    Article  Google Scholar 

  14. Lai Dayi, Chen C. Comparison of the linear regression, multinomial logit, and ordered probability models for predicting the distribution of thermal sensation. Energy Build. 2019;188-189:269–77.

    Article  Google Scholar 

  15. Hancock PA, Vasmatzidis I. Effects of heat stress on cognitive performance: the current state of knowledge. Int J Hyperth. 2003;19.3:355–72.

    Article  Google Scholar 

  16. Hancock PA, Warm JS. A dynamic model of stress and sustained attention. Human performance in extreme environments: the journal of the Society for Human Performance in Extreme. Environments. 2003;7:15–28.

    Google Scholar 

  17. Enander AE, Hygge S. Thermal stress and human performance. Scand J Work, Environ Health. 1990;16:44–50.

    Article  Google Scholar 

  18. Lai D, Liu W, Gan T, Liu K, Chen Q. A review of mitigating strategies to improve the thermal environment and thermal comfort in urban outdoor spaces. Sci Total Environ. 2019;661:337–53.

    Article  CAS  Google Scholar 

  19. Wargocki P, Delewski M, Haneda M. Physiological effects of thermal environment on office work. Healthy Build. 2009;2:1270.

    Google Scholar 

  20. Xiong J, Ma T, Lian Z, de Dear R. Perceptual and physiological responses of elderly subjects to moderate temperatures. Build Environ. 2019;156:117–22.

    Article  Google Scholar 

  21. Yao Y, Lian Z, Liu W, Shen Q. Experimental study on skin temperature and thermal comfort of the human body in a recumbent posture under uniform thermal environments. Indoor Built Environ. 2007;16:505–18.

    Article  Google Scholar 

  22. Liu Y, Wang L, Liu J, Di Y. A study of human skin and surface temperatures in stable and unstable thermal environments. J Therm Biol. 2013;38:440–8.

    Article  Google Scholar 

  23. Basar E. Brain function and oscillations: volume I: brain oscillations. Principles and approaches. Springer Science & Business Media: Berlin, Heidelberg, Germany, 2012.

  24. Başar E. Brain function and oscillations: volume II: integrative brain function. Neurophysiology and cognitive processes. Springer Science & Business Media: Berlin, Heidelberg, Germany, 2012.

  25. Başar E. A review of alpha activity in integrative brain function: fundamental physiology, sensory coding, cognition and pathology. Int J Psychophysiol. 2012;86:1–24.

    Article  Google Scholar 

  26. Kim M, Choi Y, Han J, Son Y, Chun C. An experiment on attention ability based on electroencephalogram (EEG) in different PMV conditions. In Proceeding of the Windsor conference 2014.

  27. Wang X, Li D, Menassa CC, Kamat VR. Investigating the effect of indoor thermal environment on occupants’ mental workload and task performance using electroencephalogram. Building and Environment. 2019;158:120–32.

  28. Teplan M. Fundamentals of EEG measurement. Meas Sci Rev. 2002;2:1–11.

    Google Scholar 

  29. Gargiulo G, Bifulco P, Calvo RA, Cesarelli M, Jin C, Van Schaik A. A mobile EEG system with dry electrodes. In 2008 IEEE biomedical circuits and systems conference. IEEE; 2008. p. 273–6.

  30. Ramirez R, Vamvakousis Z. Detecting emotion from EEG signals using the emotive epoc device. International conference on brain informatics. Springer, Berlin, Heidelberg; 2012. p. 175–84.

  31. Fan X, Liu W, Wargocki P. Physiological and psychological reactions of sub‐tropically acclimatized subjects exposed to different indoor temperatures at a relative humidity of 70%. Indoor Air. 2019;29:215–30.

    Article  Google Scholar 

  32. Ministry of Housing and Urban‐Rural Development of the People’s Republic of China. Design code for heating ventilation and air conditioning of civil buildings: GB50736. Beijing, China: China Architecture & Building Press; 2012. (In Chinese).

  33. Guyton AC, Hall JE. Textbook of medical physiology. Philadelphia, PA: Elsevier Saunders Press; 2006.

    Google Scholar 

  34. State Administration of Work Safety. Measures for the administration of heatstroke prevention measures. [Chinese government website]. 29 Jun 2012. http://www.nhfpc.gov.cn/jkj/s5897/201207/55314.shtml. Accessed 5 Jul 2012.

  35. ASHRAE. Environment indices in thermal comfort (chapter 8). Atlanta, GA: American Society of Heating, Refrigerating and Air‐Conditioning Engineers; 2001.

  36. Liu WW, Lian ZW, Deng QH. Use of mean skin temperature in evaluation of individual thermal comfort for a person in a sleeping posture under steady thermal environment. Indoor Built Environ. 2015;24:489–499.

    Article  CAS  Google Scholar 

  37. China Meteorological Administration. Measures for the release and dissemination of meteorological disaster warning signals. [Chinese government website]. 12 Jun 2007. http://www.gov.cn/zhengce/2007-06/28/content_2602977.htm. Accessed 28 Jun 2007.

  38. Yamtraipat N, Khedari J, Hirunlabh J. Thermal comfort standards for air conditioned buildings in hot and humid Thailand considering additional factors of acclimatization and education level. Sol Energy. 2005;78:504–17.

    Article  Google Scholar 

  39. Jin L, Zhang YF, Zhang ZJ. Human responses to high humidity in elevated temperatures for people in hot‐humid climates. Build Environ. 2017;114:257–266.

    Article  Google Scholar 

  40. Bauman F, Arens EA, Huizenga C, Xu T, Zhang H, Akimoto T, et al. The impact of humidity standards on energy efficient cooling in California. 1996.

  41. Liu J. Study on the indoor thermal environment and human thermal comfort in natural ventilation building in summer‐hot and winter‐cold zone. Master Thesis, Chongqing: Chongqing University. (In Chinese). 2007.

  42. Zhang YF, Wang JY, Chen HM, Zhang J, Meng QL. Thermal comfort in naturally ventilated buildings in hot‐humid area of China. Build Environ. 2010;45:2562–2570.

    Article  Google Scholar 

  43. Yin ZQ, Shang CJ, Liu YR, Song K, Cai J. Thermal comfort in naturally ventilated buildings in hot humid area in summer—take Haikou for example. Build Sci. 2015;31:176–182. (In Chinese).

    Google Scholar 

  44. Homan RW, Herman J, Purdy P. Cerebral location of international 10–20 system electrode placement. Electroencephalogr Clin Neurophysiol. 1987;66:376–82.

    Article  CAS  Google Scholar 

  45. Liu W, Zhong W, Wargocki P. Performance, acute health symptoms and physiological responses during exposure to high air temperature and carbon dioxide concentration. Build Environ. 2017;114:96–105.

    Article  Google Scholar 

  46. Lan L, Lian ZW, Pan L, Ye Q. Neurobehavioral approach for evaluation of office workers’ productivity: the effects of room temperature. Build Environ. 2009;44:1578–88.

    Article  Google Scholar 

  47. Lan L, Lian Z. Use of neurobehavioral tests to evaluate the effects of indoor environment quality on productivity. Build Environ. 2009;44:2208–17.

    Article  Google Scholar 

  48. ISO 10551. Ergonomics of the thermal environment. Assessment of the influence of the thermal environment using subjective judgment scales. International Organization for Standardization. 1995.

  49. Humphreys MA, Hancock M. Do people like to feel ‘neutral’?: Exploring the variation of the desired thermal sensation on the ASHRAE scale. Energy Build. 2007;39:867–74.

    Article  Google Scholar 

  50. World Medical Association. World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects. J Am Med Assoc. 2013;310:2191.

    Article  Google Scholar 

  51. Delorme A, Makeig S. EEGLAB: an open source toolbox for analysis of single-trial EEG dynamics including independent component analysis. J Neurosci Methods. 2004;134:9–21.

    Article  Google Scholar 

  52. Mognon A, Jovicich J, Bruzzone L, Buiatti M. ADJUST: an automatic EEG artifact detector based on the joint use of spatial and temporal features. Psychophysiology. 2011;48:229–40.

    Article  Google Scholar 

  53. Changeux JP. The physiology of truth: neuroscience and human knowledge. Harvard University Press: Cambridge, Massachusetts, USA, 2009.

  54. Fuster JM. Memory in the cerebral cortex: an empirical approach to neural networks in the human and nonhuman primate. MIT press: Cambridge, Massachusetts, USA, 1999.

  55. Fuster JM. Network memory. Trends Neurosci. 1997;20:451–45.

    Article  CAS  Google Scholar 

  56. Nielsen B, Hyldig T, Bidstrup F, Gonzalez-Alonso J, Christoffersen GRJ. Brain activity and fatigue during prolonged exercise in the heat. Pflügers Archiv. 2001;442:41–48.

    Article  CAS  Google Scholar 

  57. Wheeler ME, Petersen SE, Buckner RL. Memory’s echo: vivid remembering reactivates sensory-specific cortex. Proc Natl Acad Sci USA. 2000;97:11125–9.

    Article  CAS  Google Scholar 

  58. Kertesz A. Visual agnosia: the dual deficit of perception and recognition. Cortex. 1979;15:403–19.

    Article  CAS  Google Scholar 

  59. Jing S, Li B, Tan M, Liu H. Impact of relative humidity on thermal comfort in a warm environment. Indoor Built Environ. 2013;22:598–607.

    Article  Google Scholar 

  60. Fountain M, Arens EA, Xu T, Bauman F, Oguru M. An investigation of thermal comfort at high humidities. ASHRAE Transactions. 1999;105(Part 2):94–103.

  61. Lan L, Lian Z, Pan L. The effects of air temperature on office workers’ well-being, workload and productivity-evaluated with subjective ratings. Appl Ergon. 2010;42:29–36.

    Article  Google Scholar 

  62. Seppanen O, Fisk WJ, Faulkner D. Control of temperature for health and productivity in offices. ASHRAE transactions; 2004. 111(LBNL-55448).

  63. Seppanen O, Fisk WJ, Lei QH. Room temperature and productivity in office work. In Proceedings of the Healthy Buildings Congress. Lisbon, Portugal, 2006. Vol. 1, pp 243–7.

  64. Seppanen O, Fisk WJ, Lei QH. Effect of temperature on task performance in office environment. Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA, USA; 2006. No. LBNL-60946.

  65. Lan L, Wargocki P, Lian Z. Quantitative measurement of productivity loss due to thermal discomfort. Energy Build. 2011;43:1057–62.

    Article  Google Scholar 

  66. Porras‐Salazar JA, Wyon DP, Piderit‐Moreno B, Contreras‐Espinoza S, Wargocki P. Reducing classroom temperature in a tropical climate improved the thermal comfort and the performance of elementary school pupils. Indoor Air. 2018;28:892–904.

    Article  Google Scholar 

  67. Zhang F, Haddad S, Nakisa B, Rastgoo MN, Candido C, Tjondronegoro D, et al. The effects of higher temperature setpoints during summer on office workers’ cognitive load and thermal comfort. Build Environ. 2017;123:176–88.

    Article  Google Scholar 

  68. Moyen NE, Ellis CL, Ciccone AB, Thurston TS, Cochrane KC, Brown LE, et al. Increasing relative humidity impacts low-intensity exercise in the heat. Aviat Space Environ Med. 2014;85:112–9.

    Article  Google Scholar 

  69. Trezza BM, Apolinario D, de Oliveira RS, Busse AL, Gonçalves FLT, Saldiva PHN, et al. Environmental heat exposure and cognitive performance in older adults: a controlled trial. Age. 2015;37:43.

    Article  Google Scholar 

  70. Rasmussen P, Dawson EA, Nybo L, Van Lieshout JJ, Secher NH, Gjedde A. Capillary-oxygenation-level-dependent near-infrared spectrometry in frontal lobe of humans. J Cereb Blood Flow Metab. 2007;27:1082–93.

    Article  CAS  Google Scholar 

  71. Tao M, Yang D, Liu W. Learning effect and its prediction for cognitive tests used in studies on indoor environmental quality. Energy and Buildings. 2019;197:87–98.

  72. Chanjuan S, Zhiwei L, Li L. Work performance in relation to lighting environment in office buildings. Indoor Built Environ. 2018. https://doi.org/10.1177/1420326X18820089.

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Acknowledgements

The project was funded by the National Natural Science Foundation of China (No: 51778625 and 51478471).

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Correspondence to Weiwei Liu.

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Zhu, M., Liu, W. & Wargocki, P. Changes in EEG signals during the cognitive activity at varying air temperature and relative humidity. J Expo Sci Environ Epidemiol 30, 285–298 (2020). https://doi.org/10.1038/s41370-019-0154-1

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