Cerebral and systemic physiological effects of wearing face masks in young adults

Abstract

The COVID-19 pandemic led to widespread mandates requiring the wearing of face masks, which led to debates on their benefits and possible adverse effects. To that end, the physiological effects at the systemic and at the brain level are of interest. We have investigated the effect of commonly available face masks (FFP2 and surgical) on cerebral hemodynamics and oxygenation, particularly microvascular cerebral blood flow (CBF) and blood/tissue oxygen saturation (StO2), measured by transcranial hybrid near-infrared spectroscopies and on systemic physiology in 13 healthy adults (ages: 23 to 33 y). The results indicate small but significant changes in cerebral hemodynamics while wearing a mask. However, these changes are comparable to those of daily life activities. This platform and the protocol provides the basis for large or targeted studies of the effects of mask wearing in different populations and while performing critical tasks.

Facemask wearing does not impact neuro-electrical brain activity

“…Accordingly, Scholkmann et al, highlighted that the end-tidal CO 2 is not an optimal marker to assess hypercapnia induced by FM use, and suggested that a simultaneous monitoring of brain activity and hemodynamics would be needed to evaluate the relation between FM use and brain activity 26 . Our findings are similar to the results of previous research in which changes in the hemodynamic conditions of the brain in young adults who used FMs for one hour were comparable to those during daily life activities 16 . Moreover, a novelty of our study is that brain activity was monitored simultaneously with VBGs (i.e., at baseline, during FM use and post FM use), with no significant changes between the different measurement points.…”

“…Another study on the cerebral dynamic conditions of the brain and oxygenation, demonstrated small but significant changes in the cerebral hemodynamics while wearing a FM in young adults. However, the changes were similar to those of daily life activity and did not suggest a hypoxic effect 16 . Changes in cerebral blood flow (CBF) can affect brain metabolism and EEG activity 17 .…”

“…The first recorded evidence of the use of FMs to prevent the spread of a pandemic was during the Spanish flu pandemic between 1917 and 1918 16 . Its use was subsequently extended to the operating rooms in Germany and USA during the 1920s, especially for minor surgical procedures 17 .…”

Effect of surgical mask on fMRI signals during task and rest

“…It is noteworthy to mention that the findings must be considered in the context of limitations. Firstly, while we were able to measure the SPO 2 pre- and post-scan this might not reflect the true BOLD fMRI signal changes compared to if EtCO2 were to be measured and airflow was controlled in-scanner as done in 11 , 19 . Secondly, pre-scan wearing of the mask was short during the experimental session, we also modified the experiment to include a shorter task duration to allow for minimal and convenient task performance for both mask-on and mask-off states, longer duration of wearing of mask pre- and post-scan will therefore improve task responses.…”

Beyond Pathogen Filtration: Possibility of Smart Masks as Wearable Devices for Personal and Group Health and Safety Management

“…These smart masks offer inner fan control actuation and Bluetooth connectivity while using different sensing (filter, respiration rate, and air-quality checks). Commercial masks have focused on mitigating discomfort such as breathing difficulty, excessive moisture inside the mask, fogging of glasses, and hygiene problems caused by long-term use [ 35 - 37 ]. Besides protection, the masks of CLIU [ 19 ], Donut Robotics [ 20 ], and TrendyNow365 [ 21 ] aimed to overcome speech problems with mask-wearing.…”