What is the current understanding of the relationship between indoor CO2 concentrations and cognitive function?
Indoor CO2 Air-Quality Monitor (Indoor Air 2020, PMID 32557862) — in a subset of strong and consistent studies, pure CO2 at common indoor concentrations only affected high-level decision-making in non-specialized populations, as measured by the Strategic Management Simulation battery. No numeric effect size is reported for Indoor CO2 Air-Quality Monitor in the source abstract.
Source: Indoor Air 2020, PMID 32557862 ↗ · Research map · How Magellan grades evidence · evidence confidence: low
Indoor Air · 2020 · PMID 32557862 · DOI 10.1111/ina.12706
Elevated indoor CO2 and poor ventilation can affect cognitive function, with pure CO2 impacting decision-making and reduced ventilation slowing cognitive speed.
The question
What is the current understanding of the relationship between indoor CO2 concentrations and cognitive function?
What they tested
The review does not state a specific hypothesis, but rather aims to summarize existing findings regarding the cognitive impact of CO2.
How they did it
This critical review summarized results from 37 experimental studies. These studies used objective cognitive tests and manipulated CO2 concentrations either by adding pure CO2 or by adjusting ventilation rates. A subset of these studies meeting objective criteria for strength and consistency was further analyzed.
What they found
Studies with varied designs suggested that both adding pure CO2 and adjusting ventilation rates can affect multiple cognitive functions. In a subset of strong and consistent studies, pure CO2 at common indoor concentrations only affected high-level decision-making in non-specialized populations, as measured by the Strategic Management Simulation battery. Lower ventilation and the accumulation of indoor pollutants, including CO2, were found to reduce the speed of various cognitive functions but did not affect accuracy.
What it means
While both pure CO2 and reduced ventilation (with accompanying pollutants) can impact cognitive function, the specific effects differ. Pure CO2 primarily affects high-level decision-making, whereas lower ventilation and pollutant accumulation tend to reduce cognitive speed without affecting accuracy. Inconsistencies in findings highlight the need for more standardized research methods.
Limitations
Major confounding factors in the reviewed studies include variations in cognitive assessment methods, study designs, individual and populational differences among subjects, and uncertainties in exposure doses.
The paper at a glance
| Title | Indoor CO2 concentrations and cognitive function: A critical review. |
|---|---|
| Journal | Indoor Air |
| Year | 2020 |
| PMID | 32557862 ↗ |
| DOI | 10.1111/ina.12706 ↗ |
| Topic | Brain, cognition & mood |
Read the source: PubMed record (authors, abstract, full citation) ↗ · Publisher via doi.org ↗
Where Magellan uses this paper
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Indoor CO2 Air-Quality Monitor
Controlled human-exposure experiments have found that CO2 at concentrations common indoors (around 1,000-2,500 ppm) can reduce scores on tests of decision-making and higher-order cognition, and observational, real-world, and meta-analytic studies link higher ventilation (lower CO2) to better task performance in…
An indoor CO2 (carbon dioxide) air-quality monitor measures the concentration of carbon dioxide in…
Research describes the compound or intervention studied. It is not a claim about any specific product.
Cite this page
These citations point at this summary. To cite the original paper with its full author list, use the PubMed record or doi.org.
Magellan Longevity. (2026). What is the current understanding of the relationship between indoor CO2 concentrations and cognitive function? [Plain-English summary of Indoor Air 2020, PMID 32557862, DOI 10.1111/ina.12706]. Magellan Longevity. https://magellanlongevity.com/study/s188.html@misc{magellan_s188,
title = {What is the current understanding of the relationship between indoor CO2 concentrations and cognitive function?},
author = {{Magellan Longevity}},
year = {2026},
howpublished = {\url{https://magellanlongevity.com/study/s188.html}},
note = {Plain-English summary of PubMed PMID 32557862; DOI 10.1111/ina.12706; Indoor Air 2020. Reviewed by Gabriel Radu, DO},
urldate = {2026-08-11}
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