Assessment of the state of human cognitive functions when performing mental activity in an artificial hypoxic environment

Due to the emergence and development of fire safety systems based on a hypoxic environment, it is becoming relevant to assess the mental performance of specialists in conditions of oxygen deficiency.

The study aims to assess the state of the volunteers cognitive functions during the operation of fire protection facilities based on a normobaric nitrogen hypoxic environment.

The authors have assessed the state of the functional state of the body on a laboratory model of mental labor activity using biomedical methods: registration of heart rate, blood pressure and saturation. To assess the dynamics of cognitive activity indicators, they used the Stroop test and visual-motor tests. For a subjective assessment of the condition, the specialists conducted a survey.

The researchers noted a decrease in blood oxygen saturation and an increase in heart rate when in a hypoxic environment. Changes in cognitive function indicators were not associated with the effects of hypoxia, however, scientists noted a minor change in well-being both in the experimental group (increased headache) and in the entire sample (headache, sleepiness, rapid heartbeat).

The results of the study show that when simulating mental activity in a hypoxic environment for 30 minutes, the cognitive functions and well-being of employees do not deteriorate.

Limitations. Limitations are associated with the sample size, but the results obtained from individual volunteers did not contradict each other. The experts conducted a safety study of the fire protection system in artificially created conditions that did not fully correspond to the actual working conditions, but the characteristics of the hypoxic environment were reproduced. The studies were conducted only with an average oxygen content of 14% in the air, since it was assumed that this level was the minimum when using this fire extinguishing system.

Ethics. The study was approved by the Local Ethics Committee of the Izmerov Research Institute of Occupational Health (Minutes No. 2 of the meeting of the Local Ethics Committee dated 02/19/2025).

Contributions:
Shuporin E.S. — research concept and design, text writing, editing;
Chudova E.S. — research concept and design, text writing, editing;
Ilyenko O.V. — writing the text;
Glukhov D.V. — writing the text;
Eremeeva A.G. — data collection and processing;
Kalinina S.A. — data collection and processing;
Vaga I.N. — data collection and processing, editing.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interest.

Received: 15.12.2025 / Accepted: 21.01.2026 / Published: 27.03.2026

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