Exploring the physiological, neurophysiological and cognitive performance effects of elevated carbon dioxide concentrations indoors

Rationale: An accumulation of CO2 in occupied indoor spaces is correlated to negative impacts on concentration, sleepiness and aspects of cognitive performance. However factors such as: (a) the relative effect of CO2 itself compared to other pollutants; (b) the minimum necessary exposure time for cognitive performance to be affected; and (c) the physiological drivers of cognitive performance reductions due to increased indoor CO2 concentrations are not yet clear. Method: A within-subjects counterbalanced study design was used to test cognitive performance, subjective and physiological parameters of 31 volunteers during short (< 40 minutes) exposures to normal CO2 (830 ppm) and high CO2 (2,700 ppm, raised by introducing pure CO2 alongside the occupant generated CO2). The study was conducted in a small naturally ventilated office and EEG was used as an objective indicator of sleepiness. Results: The addition of pure CO2 to the room resulted in the absence of an expected learning effect in two cognitive performance test battery components without measurably affecting any of the physiological, psychological, or reported comfort, sick building syndrome and health variables measured. However participants who had slept less the previous night appeared more susceptible to becoming sleepier as a result of the increased CO2. Contributions: The results suggest (1) the addition of pure CO2 may influence aspects of cognitive performance after only short exposures (2) these changes occur in the absence of clear physiological drivers, (3) lack of sleep may mediate people’s response to higher CO2 concentration

Data for: Exploring the physiological, neurophysiological and cognitive performance effects of elevated Carbon Dioxide concentrations indoors

This supplementary data package contains the following documents: &quot;All testing materials-2.docx&quot; = Microsoft Word document containing the full experimental protocol including all the questionnaires, subjective information to be elicited, instructions for the participants. This document is of sufficient detail for the protocol to be reproduced by others. &quot;CO2 level continuous.xlsx&quot; = Microsoft Excel document containing data for the CO2 concentration experienced by all participants and aggregate graphs of CO2 concentration. &quot;Study2_SharedPure(raw data).sav&quot; = SPSS file containing all participants demographics, data for physiological, neurophysiological, questionnaire responses and all other recorded parameters. &quot;Study 2 Test_battery_details.docx&quot; = Microsoft Word document with further details of the cognitive performance test batteries used and links to the test battery provider&#39;s website. ReadMe.txt = Text file describing the information above. </span