tft display as face mask quotation

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Wearing face masksJefferson et al., 2008). During the coronavirus disease 2019 (COVID-19) pandemic, most countries and health organizations like the WHO propagated wearing face masks by early 2020 as a key strategy to reduce the spread of the severe acute respiratory syndrome 2 (SARS 2) coronavirus.

Face masks not only have a direct positive medical impact in terms of preventing the virus from spreading to those who are most vulnerable (Wu and McGoogan, 2020); they also have positive societal effects as wearing masks allows for the relaxing of other preventive measures such as strict isolation and quarantining (Mniszewski et al., 2014). However, face masks also cover, per definition, a major part of the human face, which can crucially affect social interaction. Our faces provide the key information of personal identity; additional socially important information such as trustworthiness, attractiveness, age, and sex; information that supports the understanding of speech by enabling facial speech analysis, as well as fine-grained information that allows for reading the other’s emotional state via expression analysis (Bruce and Young, 1986). We can compensate for a lack of signal for all of these facets of face processing (Grüter and Carbon, 2010); for instance, even strong cases of congenital prosopagnosia – a cognitive dysfunction that impairs or even disables the ability to recognize persons by faces (therefore, often misleadingly called “face blindness”) – are mostly overlooked in society. Although congenital prosopagnosia shows a high prevalence rate of about 2.5% (Grüter et al., 2008), we rarely encounter a person who explicitly shows this inability in real-life – the reason for this is that many of the affected persons have developed coping strategies. For instance, they compensate for the impaired capability of reading facial identification cues by means of using different sources of information such as the characteristic gait or gesture, or by using information from other modalities, such as the characteristic voice pattern of a person. But even with successful compensation, the efficacy of processing is often reduced. This is also reflected in the confidence of one’s assessments. Actually, the affected persons are susceptible to losing a part of the multichannel-multisensory integration possibilities to crosscheck and validate their assessments. Some of these signals that faces provide are processed very fast (identity, Carbon, 2011; gender and attractiveness, Carbon et al., 2018; emotion, Willis and Todorov, 2006), although the validity of the final assessments is under great dispute (Russell, 1994; Rojahn et al., 2000).

With regard to expression analysis, different studies have showed that we are far from perfect in assessing the emotional state of our counterpart. This is especially the case when we just rely on pure facial information (Derntl et al., 2009) without knowing the context of a scene (Aviezer et al., 2008). Another factor that lowers our performance in correctly reading emotions from faces is the static view on faces without any information about the dynamic progression of the seen expression (Bassili, 1979; Blais et al., 2012, 2017). A partial occlusion of the face (Bassili, 1979), e.g., by sunglasses (Roberson et al., 2012) or by scarfs (Kret and de Gelder, 2012), is a further obstacle to accurately reading emotions from facial expressions (Bassili, 1979). Face masks or community masks, as the ones commonly worn during the COVID-19 pandemic to shield the mouth and the nose, cover about 60–70% of the area of the face that is relevant for emotional expression, and thus, emotion reading (e.g., ~65% in the case of the depicted persons in our face set – exact numbers are hard to tell; we can only rely on rough estimations as indicative face areas differ from person to person). Crucially, these masks cover an area of the face that is crucial for the effective nonverbal communication of emotional states. Although specific research on the impact of such face masks on emotional recognition is missing, there are some indications from research on the effect of different kinds of facial occlusions. An important source of data is the so-called “Bubbles”-paradigm that make use of a general technique developed by Gosselin and Schyns (2001). This technique allows for identifying the specific visual information that is most relevant to human categorization performance, for instance, information needed to express and read emotions. Of special relevance regarding the Bubbles technique are findings that specifically addressed the specific parts of faces that are most indicative for certain emotional expressions (e.g., Smith et al., 2005; Blais et al., 2012). Blais et al. (2012), for instance, revealed the paramount importance of processing the mouth region. With a clever combination of a Bubbles paradigm and dynamic face stimuli from video sequences of half a second length starting with neutral expression that naturally deployed into an expressive state ending with the apex of the expression, the authors even demonstrated that this dominance of the mouth region persisted nearly over the entire period of time. Other paradigms comprise the presentation of top vs. bottom halves of faces (Bassili, 1979) or the partial occlusion of target faces with ecological valid items such as a niqāb (Fischer et al., 2012), a shawl, or a cap (Kret and de Gelder, 2012) in order to test for differences in the participants’ emotion reading performance. These different paradigms operate with very different stimuli, and they were used with samples from different populations. In any case, the found effects are informative for the present study as specific emotions were primarily hard to read in faces with occlusions of the mouth area; for instance, happiness (for occlusions by a rectangular cardboard, see Bassili, 1979; for occlusions by a niqāb, see Fischer et al., 2012; Kret and de Gelder, 2012) or sadness (for occlusions by a rectangular cardboard, see Bassili, 1979; for occlusions by a niqāb, see Fischer et al., 2012; Kret and de Gelder, 2012), while anger, for instance, was affected much less and remained observable (for occlusions by a rectangular cardboard, see Bassili, 1979; for occlusions by a niqāb, see Fischer et al., 2012; Kret and de Gelder, 2012). Taken together, these studies provide excellent basic data on how strongly and selectively occlusions of the mouth area affect the recognition of facial emotion, but they did not specifically address how face masks impact the reading of different emotions. The manipulations realized in those paradigms are neither quantitatively nor qualitatively analogous to the actual practical use of face masks. By using face masks, we can also check whether they operate as a kind of psychological marker for disease, a deliberate disguise, or indicate some special status of the wearer; it is also possible that a face mask can signal a potentially dangerous situation by triggering anxiety-related associations – a marker operating in such a way could modulate the interpretation of the entire social situation and so also of the specific emotional expression. The results of the existing studies show some clear common ground, for instance, a relatively high consensus that covering the lower face parts, especially the mouth (Blais et al., 2012), yields reduced performance in assessing a happy emotional state (e.g., Kotsia et al., 2008; Eisenbarth and Alpers, 2011; Fischer et al., 2012). For other emotional states than happy faces, however, there are quite contradictory results to be found in the literature, e.g., for fear detection (in favor of higher relevance of the eyes, see Bombari et al., 2013; in favor of higher relevance of the mouth, see Kotsia et al., 2008). There is even evidence that a partial covering of the face might lead to better performance due to blocking out irrelevant or deceptive information in faces (Kret and de Gelder, 2012). Laypersons, for instance, were more accurate in detecting deception in persons who wore a niqāb than in persons who did not (Leach et al., 2016). Inconsistent results such as angry faces attracting more attention to the eyes than the mouth (Eisenbarth and Alpers, 2011) while the occlusion of the mouth resulted in lower accuracy of detecting anger (Kotsia et al., 2008) have to be interpreted with caution as we do not know the causal or temporal interdependence of such processes. Specific types of occlusions might interfere with different emotions: for example, the mouth seems important for the detection of happiness and fear, but the eyes are more relevant for anger, fear, and sadness (Bombari et al., 2013).

The present study specifically tested how a common face mask, which, for instance, dominates social scenes during the COVID-19 pandemic, changes the efficacy of emotion reading expressions displayed by different faces. Besides recognition sensitivity, in order to understand everyday life problems in effectively communicating when wearing face masks, we were particularly interested in the confusion of certain emotions with other emotional states due to an increase in signal ambiguity.

The needed sample size of N = 36 was calculated a priori via power analysis (Faul et al., 2007) targeting a repeated measures analysis of variance (ANOVA) with six groups (emotions) and two measurements (mask vs. no mask) and the ability to detect a medium effect size of f = 0.25 (Cohen, 1988), given an α = 0.05 and a test power (1-β) = 0.80. From our entire set of data from 41 participants [Mage = 26.7 years (18–87 years), Nfemale = 30], we could use all data sets as all participants reached the pre-defined criterion of showing at least a performance of correctly identifying emotional states in 50% of the cases where faces were presented without masks (actually, the performance was much higher, see results). This slightly higher actual than needed number of participants resulted in an achieved post hoc test power of 0.88.

All face stimuli were obtained from the MPI FACES database (Ebner et al., 2010) by a study-specific contract effective by 27 April 2020. As base faces on which we later applied face masks, we used frontal photos of 12 Caucasians (six females and six males) who belonged to three different face age groups (young, medium = middle-aged, and elderly), yielding two persons per face sex × face age group cell. For each person, six different pictures were used that showed the emotional states angry, disgusted, fearful, happy, neutral, and sad. For the application of face masks to all of these 72 original pictures, we photographed a typical homemade (beige) community mask. The image of the mask was cut out via Photoshop and individually applied to the different face versions. Realistic shadows were added to create maximally realistic and plastic pictures of persons wearing a face mask (Figure 1).

Figure 1. A person showing six different emotions without a mask (A) and wearing a mask (B). Original material from top row stems from MPI FACES database (Ebner et al., 2010).

The experiment which ran on the SoSciSurvey online platform was conducted between 15 May (10:01 local time) and 18 May (19:45 local time) during the COVID-19 pandemic when general legal obligations to wear masks in Germany were already in action. Prior to the experimental session, written informed consent was obtained from each participant. All data were collected anonymously. Each participant was exposed to the complete set of stimuli one after another, with the order of stimuli being randomized across participants. Participants were asked to spontaneously assess the depicted person’s emotional state from a list of six emotions reflecting the same compilation of emotions shown by the different versions of the faces (angry, disgusted, fearful, happy, neutral, and sad). Personal confidence for each assessment had to be indicated on a scale from 1 (very unconfident) to 7 (very confident). There was no time limit for giving a response. The general study design (psychophysical testing) was given ethical approval by the local ethics committee of the University of Bamberg. The entire procedure lasted approximately 20–25 min.

Overall performance for correctly identifying facial emotions in faces without masks was quite remarkable, M = 89.5% (chance rate = 16.7%) with no participant performing below an overall rate of 76.4%; this high recognition rate outperforms the accuracy of assigning emotional states to faces documented by many other studies (for anger and disgust 56.9 and 58.9%, respectively, see Aviezer et al., 2008; 73.2, 73.7, 63.2, and 72.2%, for sadness, anger, disgust, and fear, respectively, see Derntl et al., 2009). As shown by the mean data for each emotional state (Figure 2), presenting a mask on faces showed a clear performance drop in reading emotions in faces. With the exception of fearful and neutral faces, for which ceiling performance effects were observed, all emotional states were harder to read in faces with masks.

Figure 2. Mean percentage of correct assessment of the emotional states for faces with masks (blue) or without masks (red) on the face. Error bars indicate confidence intervals CI-95% based on adjusted values for taking within-subject variances into account (Morey, 2008). Asterisks indicate statistical differences between conditions of wearing and non-wearing on the basis of paired t-tests: ****p < 0.0001; ns, not significant.

We tested the effect of wearing masks on the performance of emotional reading in faces by means of LMMs with face mask (face with a mask vs. without a mask) as a fixed factor against a base model (model #0) which only contained the participants and base stimuli as random intercepts and face emotion as fixed slopes – FS (fixed factors). We furthermore tested, in a successive way, the effect of the sex and age group of the face stimuli by adding these factors as FS – including all possible interactions of all fixed factors. p-values were obtained by likelihood ratio tests of the subsequent models against the respective one-step less complex model. The coefficient of determination for each model was calculated via a likelihood-ratio test utilizing the toolbox MuMIn (Barton, 2019). See Table 1 for detailed results.

Table 1. Linear mixed effect analysis of different models in comparison to a simple base model (model #0), separated by the two tested dependent variables %correct (percentage of correct emotion classifications) and confidence (for correct emotion classifications).

Linear mixed effect analysis revealed that both dependent variables were impacted by the factor face mask. Furthermore, face age group played a role in explaining the variance of both dependent variables (reading the emotional status of elderly faces was more difficult than reading it from middle-aged or young faces; this effect was pronounced when faces were shown with masks) – for face sex, in contrast, we only found an effect for the accuracy of emotion reading.

As face sex as well as face age group were effective in predicting the correctness of reading the emotional state of faces, Figure 3 shows the differentiated data for the three-way interactive effect with face mask. Lower performance in assessing emotions in masked faces was found for most emotions and sex and age groups.

Figure 3. Mean percentage of correctly assessing the emotional states with masks (blue) or without masks (red) on the face, split by face sex and face age group. Error bars indicate confidence intervals CI-95% based on adjusted values for taking within-subject variances into account (Morey, 2008). Asterisks indicate statistical differences between conditions of wearing and non-wearing on basis of paired t-tests: *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001; ns, not significant.

Based on the finally selected models with face mask, face sex, and face age group being included in terms of fixed slopes and their interactions, we obtained several effects of small, medium, and large size (Table 2). Most importantly, regarding the major question of the study, face mask had a medium-sized effect on the performance of assessing the emotional state of a face and a large-sized effect on the confidence of one’s own assessment (for correct emotion classifications).

Table 2. Statistics of all involved fixed effects terms of the linear mixed effect analysis for the final models (model #3), separated by the two tested dependent variables %correct (percentage of correct emotion classifications) and confidence (for correct emotion classifications).

As shown in Figure 4, the confidence data showed a similar but not identical results pattern compared to the percentage of correct assessment data in Figure 2. Interestingly, confidence data reflected the impact of a face mask emotion reading even more clearly. For confidence ratings, fearful and neutral faces were also impacted, probably due to a lack of ceiling effects.

Figure 4. Mean confidence of assessing the emotional states (for correct classifications) with masks (blue) or without masks (red) on the face. Error bars indicate confidence intervals CI-95% based on adjusted values for taking within-subject variances into account (Morey, 2008). Asterisks indicate statistical differences between conditions of wearing and non-wearing on basis of paired t-tests: *p < 0.05, ****p < 0.0001; ns, not significant.

A drop in performance in reading the emotional states of faces with masks can somehow be expected as being much harder when most visual information of the lower half of the face is blocked out. To understand how the lack of information is dealt with, it is important to look at the specific confusion of individual emotional states – when and in which way are emotions misinterpreted when face masks are worn?

In order to learn about these misinterpretations, we generated confusion matrices for the viewing conditions for faces without masks and with masks (see Figure 5). When faces were shown without masks, the accuracy was much higher, as is indicated by clear matches between expressed and perceived emotions. With the exception of the emotional state sad, accuracy was above 83%, but sad, in particular, was often confused with disgusted (20.3% of the cases). As soon as we applied masks to the faces, this overall very high performance broke down dramatically and characteristic confusions became apparent. For instance, all emotional states with the exception of fearful were repeatedly confused with a neutral state. Sad was often confused with disgusted and neutral, and angry was confused with disgusted, neutral, and sad. Most drastically was the misinterpretation of disgusted as angry, which showed up in nearly 38% of the cases, although such a confusion did only happen in 2% of the cases where no face mask was used. In previous studies, it was shown that, in particular, the recognition of the emotional states happy and sad, and to a smaller degree angry, rely strongly on the processing of the lower facial part, especially the mouth area (Bassili, 1979; Fischer et al., 2012; Kret and de Gelder, 2012). And, exactly these emotional states were hard to decipher and easily confounded when a mask was applied to the target face.

Figure 5. Confusion matrix of expressed and perceived emotions. Top matrix: faces without masks, bottom matrix: faces with a mask. Percentages compile up to 100% for each expressed emotion. The deeper blue the cell, the higher the score of this cell.

Wearing face masks, even very simple homemade models, is an important measure to effectively decrease the chance of transmitting respiratory diseases (van der Sande et al., 2008), as is also suggested by the analysis of past pandemics such as the 1918 flu pandemic caused by the H1N1 influenza (Bootsma and Ferguson, 2007). People in countries where face masks have not been widely used in the past may still be ambivalent about wearing them. Acceptance of wearing a mask is low when surrounded by too many non-wearers – people start to feel “strange” (Carbon, 2020); additionally, there are obvious handling problems and ergonomic issues including changed airflow characteristics which do not support the wearing of masks. Yet, the usage of masks is becoming an everyday practice all over the world, including Europe where the wearing of masks was uncommon before the COVID-19 pandemic.

In the present experiment, we tested the impact of face masks on emotion reading, which may have important implications for everyday social interaction. We confronted participants with faces showing six different emotions (angry, disgusted, fearful, happy, neutral, and sad). The results indicate that emotion recognition was strongly reduced with the exception of fearful and neutral faces, which is compatible with parts of the literature employing different types of occlusion, for instance, by rigidly covering the mouth area with cardboard (Bassili, 1979), using the Bubbles technique (Blais et al., 2012), or, much closer to the present study, with ecologically valid paraphernalia such as a niqāb (Fischer et al., 2012), a shawl or a cap (Kret and de Gelder, 2012). For fearful faces, as shown before in the literature (but see Kret and de Gelder, 2012; Bombari et al., 2013; Wegrzyn et al., 2017), the eye region, which was not occluded by the mask, provides most of the emotional information indicative for this emotional state. For neutral faces, the results have to be interpreted in a completely different and cautious way: although performance for recognizing a neutral state was not directly decreased, many emotional states such as happy, sad, and angry were misinterpreted as neutral, so the genuine emotional state was not perceived anymore. Other emotions such as disgusted were confused with angry, and this qualitative misinterpretation – which is quite impactful (a person who does feel aversion to a very specific thing in a certain situation and who expresses this spontaneously might be interpreted as an angry and potentially aggressive person) – was found in more than one third of all assessments of disgusted faces wearing a mask.

To further qualify these effects, we have to make it clear that the face stimuli originated from a scientific database, which is aiming to show emotions with maximal clarity and in a very pronounced fashion. These requirements were nearly perfectly achieved when we look at the very high performance data for the original faces without masks. There was hardly any confusion of different emotional states (with the exception of sad faces which already showed substantial confounding with disgusted at a level of one-fifth of the cases). Such a high performance is hardly achievable in everyday life when faces are inspected that show much lower degrees of emotional expression. Furthermore, in an everyday life scene, we will typically show lower levels of attention and will invest less time in inspecting the face of a counterpart. This means that in natural contexts, the impact of face masks on reading emotions could even be stronger. It could further be intensified with increased age: as the results of some empirical studies indicate, older adults have more difficulty recognizing some of the basic emotions (e.g., disgust, happiness, and fear), and even intense problems in recognizing other basic emotions such as anger and sadness (Ruffman et al., 2008). On the other hand, we also have to make clear that the data presented here are based on the processing of graphically manipulated stimuli, not on faces wearing masks in a real world scenario. We opted for such a solution because if we photograph the same person wearing a mask vs. wearing no mask under the condition of six different emotions, the change in emotional expression is no longer controllable. Experimental designs are always in the difficult situation of finding an optimal balance between internal and external or even ecological validity. So, we took great care to present realistic and highly plausible stimuli which were graphically post-processed by adding shadows and adjusting them to the sizes and directions of the heads. Having taken this path, we cannot exclude that people in real-world settings will adjust to the situation of wearing masks and compensate the lack of expression options by amplifying their expressions. Everyday life experience contradicts this idea as people frequently report such confusions of emotions and complain about the lack of confidence in others’ emotional states, which we have also documented in the present paper.

Face masks may complicate social interaction as they disturb emotion reading from facial expression. This should, however, not be taken as a reason or an excuse for not wearing masks in situations where they are of medical use. We should not forget that humans possess a variety of means to interpret another’s state of mind, including another’s emotional states. Facial expressions are not our one and only source of information; we can also take recourse to body posture and body language to infer the emotional states of our counterpart. The voice characteristic adds indications from another modality (Golan et al., 2006), and the bodily context (Aviezer et al., 2008), the head orientation (Sauer et al., 2014, but also just inspect Figure 1 with a clear sign of specific head orientations as a by-product of emotional expression), and, of course, also the social context (Mondloch, 2012) will provide further information. Direct verbal communication even helps to understand the very fine-tuned state of a mind. We have options, and it is essential to make use of them not only when being the receiver of socially relevant information but also when being the sender. And, we should use and optimize those options which we can best play and which suit us best; this not only applies for times and situations where we cover parts of our face due to health or cultural reasons but extends to cases where the ability to express emotions is affected (e.g., due to neurological diseases, Jin et al., 2017; Lee et al., 2019): some people might have only a very limited repertoire of gestures and other body-oriented expression abilities but they might be good verbal communicators. Emphasizing alternative and additional communicative channels (see Aviezer et al., 2008), we can provide sufficient information to keep social interaction going in a different, yet, effective way.

The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number can be found at: https://osf.io/ka3s6/.

This study was approved in terms of the general study design (psychophysical testing) and was given ethical approval by the local ethics committee of the University of Bamberg (protocol 2017-08-18). The patients/participants provided their written informed consent to participate in this study.

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

We would like to thank the MPI for providing the base stimuli for the present study. We also thank our student assistants for having put intensive effort into recruiting many of the participants, and special thanks goes to Christian Meyer for processing the mask stimuli and Vera M. Hesslinger for very fruitful discussion and critical reflection of this study.

1. Face masks show a great variety of forms and technologies; within the present paper, we will focus on masks that look like simple surgical masks and that people can fabricate themselves, so called community masks.

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The coronavirus disease 2019 (COVID-19) pandemic is currently perceived as one of the greatest global threats, not only to public health and well-being, but also to global economic and social stability. While the first two decades of the third millennium were characterized by crisis—most notably the economic downturn of 2008 and the looming climate change—the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus originating from China has given rise to most drastic societal and political responses. These included measures as severe as states forbidding citizens from leaving their homes and effectively shutting down all social and economic activities (1). In Europe, Italy was the first country to officially detect the presence of COVID-19 in its territory, and it swiftly adopted measures to contain its spread (2–4). Within a few weeks, the epidemic progressively spread across Europe. Because of the novel situation and the contradictory opinions of experts, including representatives of the scientific community and World Health Organization (WHO), the level of threat caused by the disease appeared unclear (5). The assessment of the perceived risks of the disease varied in the public discourse—some considered it just as “a stronger influenza”; others drew parallels with the very deadly Spanish Flu outbreak in the 1918–1920, and many were simply not sure what to believe. Nevertheless, most felt the novel and unpleasant feeling of being vulnerable to the invisible threat of the infection (i.e., to be the ones in danger) or to be contagious themselves (i.e., to be the danger).

A variety of public health and hygiene measures have been initiated; the most visually noticeable perhaps is the wearing of face masks. The medical research on the use of face masks as personal protective equipment (PPE) against SARS-CoV-2 transmission was interpreted very cautiously, and the initial guidance from health officials was conflicting (6). The WHO advice was conceived to avoid unnecessary paternalism and at the same time be comprehensive in discussing different medical aspects of mask use. However, it was updated several times, shifting from initial statements that face masks are not to be worn by healthy individuals toward gradual adoption of face masks as useful in slowing community transmission. In particular, “…WHO has updated its guidance to advise that to prevent COVID-19 transmission effectively in areas of community transmission, governments should encourage the general public to wear masks in specific situations and settings as part of a comprehensive approach to suppress SARS-CoV-2 transmission” (7). Gradually, face mask use has been recognized as a suitable measure within the scientific community (8–12), if nothing else due to the application of the “precautionary principle” in the face of an acute crisis (13, 14). This has since been backed up by empirical observations (15, 16).

Different, mandatory or voluntary, practices, and contradictory indications about the utility of face mask wearing were introduced across affected countries. Generally speaking, face masks have been adopted as one of the measures to reduce the COVID-19 spread across Europe, despite the fact that wearing masks in Europe is not common or familiar, and it is often associated with Asian countries (17). The social conventions and personal meanings of face mask use have received relatively little attention. Its use is deeply connected to social and cultural practices, as well as political, ethical, and health-related concerns, personal, and social meanings (18, 19).

In this study, our aim was to address three aspects of face mask wearing—public policies, individual behaviors and attitudes, and the collective experiences of the affected communities. In order to develop insights into the wider meanings of face mask wearing beyond (just) preventing the spread of infection, we tapped into the expertise of a scholarly interdisciplinary network, the Navigating Knowledge Landscapes—NKL (http://knowledge-landscapes.hiim.hr/), predominantly consisting of Europe-based scholars. The network is dedicated to furthering research on topics related to medicine, health, and society and comprises academics working across the disciplinary spectrum. We invited NKL members in May 2020 to provide their observations on the topic, also based on their professional experience. They were asked to describe the face mask usage in their countries and provide their subjective standpoints and/or those from their social environment. Subsequently, these testimonies within the specific time window (May 2020) containing narratives on face masks from the contributing experts were thematically analyzed using the method of qualitative descriptive analysis (20, 21).

The invitation to write their views about face mask wearing was sent by e-mail to 97 experts, all members of the interdisciplinary research network Navigating Knowledge Landscapes (NKL; http://knowledge-landscapes.hiim.hr/). The invitation was sent on May 11, 2020, and the responses were collected until May 26, 2020 (over 16 days" period). The experts were asked to contribute a single-page narrative structured in four parts, framed as follows:

• Part 1: What are the rules adopted in your country about face mask wearing? What would be the overall approach for use of the face masks in your community (government instructions, availability, the citizen compliance)?

• Part 2: What is your individual/personal attitude and practice in relation to face masks? If applicable, start with good practice and end with what you consider to be mistakes.

• Part 3: How do you judge the behavior of people you encounter? Face masks (or no face masks) and interpersonal interactions. Again, start with positive and end with negative.

Twenty-nine scholars responded (30% of those invited), providing 27 contributions (two contributions were coauthored). They were from 22 countries, 20 from Europe (Albania, Austria, Bosnia and Herzegovina, Croatia, Czechia, Estonia, Hungary, Italy, Ireland, Norway, Poland, Portugal, Romania, Serbia, Slovenia, Spain, Sweden, Turkey, Ukraine, and United Kingdom) and two from Asia (China and South Korea). The contributors belonged to the following academic disciplines: biology (2), economics (1), engineering (2), information systems (1), law (1), medicine (6), philosophy (5), psychology (1), and sociology (10).

The contributors as experts are all highly educated (Ph.D., holders or Ph.D., students), and most of them are employed in academic institutions and perform research activities in their respective disciplines. The authors of this study were among the contributors.

The testimonials were based on the aforementioned open-ended questions and narrative in style. “Face mask” was used as the umbrella term for all types of face coverings, from the custom-made cotton scarves to disposable surgical masks and medical-grade N95 respirators. This was done to preserve the authenticity of these narratives without going into detail about the medical or microbiological features of the different types of face coverings. In the same way, grammatical or vocabulary use of non-native English speakers was kept as it was. The contributions received were collected and published as a citable open-source dataset at Mendeley Data repository (22).

The contributions were thematically analyzed by employing a qualitative descriptive approach (23). We chose this method because it aimed to provide “rich descriptions about a phenomenon, which little may be known about” [(23), p. 3] and was particularly useful for exploratory research such as our study. It is characterized by staying close to the empirical data, instead of seeking to provide a more conceptual interpretation of the phenomenon in question. Moreover, open-ended questions address different aspects of the same topic and allow formulating answers that could let respondents to frame face mask wearing according to their own personal views (24).

Concerning the thematic analysis, we divided testimonials in three categories. The first category captured the situation in the respondent"s country; the subcategories we were interested in were the regulatory framework and the supply situation in each respective country. The second category captured experts" own use of masks. Here we focused in particular on whether and in which situations they reported to wear (or not wear) masks, what kind of face covering they used, and the meaning they ascribed to masks (e.g., mask wearing as a symbol of social cohesion). Third, we categorized the participants" accounts regarding the practices and attitudes of mask wearing they observed in others. We created an MS Excel file in which we collected the respondents" statements on these different categories. In a subsequent step, we analyzed the data for patterns and recurring topics. We looked for country-specific differences and similarities in regulations and practices. Moreover, we also paid close attention to how the experts made sense of their experiences with mask wearing and how the issues addressed were expressed (e.g., experts referring to folk stories, metaphors, or past incidents). When presenting our research results, we focused on the topics we identified as prevalent through our inductive analysis, and we contextualized it based on the published research.

The narratives analyzed in this study were given with the full consent of the people who wrote them and were made available for public access as an open-source repository for the research purpose (22). All the authors provided their consent that the narratives are published in the repository under their full name and affiliation and that they can be used for research purposes. The authors were cited here under their full names, recognizing their authorship of the narratives and their contribution to the dataset collection. The study received ethical approvals from the Ethical Committees of the University of Edinburgh, Scotland, UK and the University of Zagreb, Faculty of Croatian Studies, Croatia.

The use of a face mask—of various specifications according to the required degree of protection/function—is part of the PPE required in several professional activities, most noticeable in healthcare. One of the participants in this study, who works in healthcare, described her own experience in terms of the caring features of the face masks from medical to communal setting.

“As an obstetrician–gynecologist, I am used with the mask, I feel it a part of my professional life, and I am trying to convince people that there is no way of considering the mask as an enemy but as a protection-like and umbrella against the rain, like a coat against the cold—and as a sign of civilization to protect our colleges and people around.” [Iuliana Ceausu, Romania]

The contextual transfer of face mask use from healthcare settings to public spaces is precisely the aspect of making the “outside world” closely resemble scientific apparatus. This includes measuring its success as a feature of the social power derived from the accuracy of the scientific prediction. For instance, Latour (25) specifically examines the public nature of Pasteur"s demonstration of the efficacy of the process of animal vaccination by making a “prophecy” that vaccinated cattle on a pilot farm will survive, while other infected animals will perish. In the same way, the (anecdotally) apparent success of the use of face masks reinforces the belief in their utility and efficacy:

“The people working in the shops would use the masks too… I see familiar faces of the employees all the times of lockdown, although they spend all time in the shop with many different customers, obviously they did not get sick. This was for me a major reassuring fact that the danger is not so high as it could be seen from the media.” [Srećko Gajović, Croatia]

Following initial confusion around the utility of face masks for slowing down the spread of COVID-19 pandemic, there is increasing scientific evidence to support citizens" wearing of face coverings, albeit the public health advice and legislation vary from country to country. A recent study in Germany indicated that a mandatory approach to face mask wearing achieved better compliance than voluntary one, and it was perceived as an effective, fair, and socially responsible measure (27).

In our study, accordingly, the reported country policies differed across rather a wide spectrum of approaches—ranging from legally mandated instructions to cover one"s face in all public spaces reinforced by financial penalties (i.e., payable fines), to recommendations only, official indifference, or advice against this practice (Table 1). We were interested how these policies related to the concurrent COVID-19 situation expressed as total number and increase of cases per million people in these countries during the period when experts made their contributions. We observed an obvious trend showing that the countries with more strict rules had better epidemiological situation than those not mandating the face mask usage (Table 1).

In some countries, face mask–related policies did not need to be prescribed as this was part of existing established habits; in the same way, no fines are necessary to get people to wash their hands. In particular, since the SARS epidemic in 2003, in many Asian countries, masks are customary wear used to protect against seasonal flu and the common cold. In China and South Korea, they are also employed to protect citizens from pollutants (17, 29).

“In South Korea, it is common to wear a mask to keep the cold from getting worse in the winter and to prevent the spread of cold to others. Also, as the yellow dust from China and fine dust became much severe, it was common for many people, especially children, to wear masks even before the corona crisis. For this reason, many families even had a lot of masks in their homes before the corona crisis. Personally, I"m familiar with wearing a mask, and I"d like to wear it in order not to harm other people, as I may be a potential patient.” [Jiwon Shim, South Korea]

In contrast, in the West, the use of face masks is rare in social settings. Hence, because of the public visibility of face mask usage, face masks became an ideological symbol in some countries, with divergent political mindsets governing their adaption or rejection (17). Political dividing lines were particularly apparent in the United States, where the President refused to wear a mask until the last days of July 2020, when the floundering poll numbers and the increasing numbers of COVID-19 cases prompted the need to recommend this health protection device (30). Thus, in the United States and elsewhere, face masks were used by citizens to express their opinions in public.

“At the beginning of the pandemic, the use of masks had political connotations: since the government advised against their use, their wearing was even considered a form of political opinion.” [Iñigo de Miguel Beriain, Spain]

The public statement made by wearing (or not wearing) the face mask did not only address the political standpoints but have also been used to communicate various societally relevant statements, i.e., stating ethnical, religious, or cultural affiliations (31). For instance, many countries that before COVID-19 banned face coverings in public spaces are now mandating it, supporting the idea that the past bans were motivated on the basis of religious/cultural beliefs (17).

“Ethical and moral dilemmas have already risen, especially in countries where Muslim minorities live. If you ban a burka covering the face due to security reasons, how would you deal with massive usage of face masks?” [Gentian Vyshka, Albania]

“The decision to wear a face mask is not an easy one. Traditionally, face coverings are an indicator of political persuasion and religious belief. I perceive that the widespread covering of one"s face in public is a significant cultural and social shift in Ireland.” [Ciara Heavin, Ireland]

The collected narratives indicated that the contributors had a clear standpoint on their own face mask usage and developed arguments to support their decisions to wear or not to wear face masks.

“As soon as I leave the house and find myself in the supermarket or in public places, I wear a mask. However, I do not wear a mask when I take a walk in the forest. I started wearing it even before it became mandatory. I think it is important to wear masks, especially to avoid endangering others, e.g., elderly people. I find it unspeakable when people who wear masks are ridiculed by those who do not wear masks. At least that"s what happened to me in the beginning, before the mask duty… Many thought that the people wearing masks would want to protect themselves in particular. Very few thought that people wearing masks wanted to protect their social environment.” [Melike Sahinol, Turkey]

“My personal view is that as long as the spread of the virus is under control (as it currently is), there is no need to make the masks obligatory. I personally have not worn a mask (have not purchased any either) with the exception of when I visited healthcare institution (provided by them). I must also say, though, that none of my family members are considered a vulnerable population. If my grandmother would live with us, I might think differently.” [Kadri Simm, Estonia]

What was exemplified in many narratives is that individual usage is not meant predominantly for an individual"s self-protection, but the decision was based on people"s relationship to others. The citizens" question “should I protect myself” evolved into “can I protect the others?”

“I wear disposable masks, understanding they protect others from me, more than me from others. I wear them to demonstrate responsible behavior and attitude to benefit of society.” [Predrag Pale, Croatia]

The experiences of interaction with others in relation to face mask wearing were mentioned frequently, indicating the importance of the social context of individual behavior.

“I experienced cases when my request to keep distance or to take on a mask properly was treated offensively or as a sign of mistrust…” [Christina Nasadyuk, Ukraine]

“I put it on when I go to the grocery store because at the early stage of the pandemic, I was warned by the lady working at the counter that I am putting her life ‘in danger by not wearing a mask." Obviously, I did not want to take chances with her life again, so I purchased one of those cloth masks.” [Vanja Kopilaš, Croatia]

However, many testimonies pointed out that masks have not been used properly. The health risks of incorrectly wearing a face mask represent an important argument against the use of face masks as a public health measure (32).

“…25% wore masks improperly, on their necks, or covering only their mouths, but not noses. …They do not know how to put the mask on, and when they remove their masks, they touch the outside of the mask, which is inappropriate and wrong.” [Izet Mašić, Bosnia and Herzegovina]

“Also, one can observe many cases of half-compliance or sham compliance. For instance, people do wear masks, but slide them down onto their chins or take them off completely while talking to someone on the street or speaking on the phone. And this is all a performance, keeping their masks somewhere within reach in case of the sudden emergence of police officers, who are indeed issuing fines for not wearing a mask.” [Aleksandra Głos, Poland]

“During the early stages of disease progression, mask wearing was not a common practice, mainly due to the complete absence and highly inflated prices in stores.” [Rostyslav Bilyy, Ukraine]

“I do not use face mask. In the early stage of the COVID-19 epidemic in Norway, my understanding was that available masks should be reserved for people in the health and caring sector.” [Anna Lydia Svalastog, Norway]

“I think the biggest concern is that the mask has been in short supply for a long time, and that its trade has not been subject to official pricing, so prices have been uncontrolled… The mask was in short supply when emergency was announced, but it is now available in many places and can be obtained at the checkout of almost every grocery store if someone started shopping without it.” [Norbert Buzas, Hungary]

The shortage of masks ignited a burst of creativity in producing homemade masks, with a proliferation of tutorials for their production on the Internet and social media.

“Nowhere was possible to come to the face masks. Typical situation: the government did announce decree, but it did not provide the means for its implementation. We as ordinary citizens need to improvise with needlework of masks at home as well. Taking in regard that immediately rapacious war profiteers did appear by selling masks the needlework of masks at home was even not the worst solution.” [Franc Mali, Slovenia]

“Although during the first weeks there was lack of masks and respirators, it was great how many people proved their creativity. It concerned not only the textile reusable masks, but also design and development of respirators with higher level of protection. They were mostly printed on 3D printers. Later on, some of the approved types were taken by larger producers, and mass production started.” [Lenka Lhotska, Czechia]

Besides being shaped by public discourse and social norms, risk perception also has a strong personal element. Some people seem like they do not care; others are quite relaxed, and some are more cautious. As for COVID-19, conflicting perspectives and emotions and even the psychological entrapment syndrome known as “cabin fever” (i.e., referencing long winter isolation in a small cabin) have been reported (33). Here, restricted microenvironments and quarantine are felt as secure places. The additional challenges were noticeable during the shift from the lockdown phase and the beginning of the so-called “phase 2” or “reopening” when people were allowed to leave their home again.

“‘Convivere," i.e., ‘live together with" the virus is the expression used by experts and media, to describe the phase 2, but this narrative could result quite distressing: how glad would someone be when living with a submicroscopic entity, that is such dangerous?” [Lucia Martinelli, Italy]

During this second phase, going back to living with “the others” demands new social behavior/etiquette combined with increased safety measures. The face masks start to be part of the new everyday rituals of saying hello, having a coffee together, and protecting each other. The role of peers in shaping the behavior of others is significant. People not committed to wearing mask can feel peers" pressure to comply. Moreover, “a collapse between the status of being at risk and being a risk” was noted (34–36).

“The face mask, I realize, signals both positions, at the same time as it doesn"t provide a definite answer: are you the risk object or the object at risk? Saying this, my individual attitude toward face masks cannot be pried apart from the social acceptance and use of the same. As long as the nonuse of face masks constitutes the norm, I will most likely interpret the usage as deviant and worrying. On the other hand, if the vast majority of the Swedish population would wear face masks, I would most likely start wearing a face mask as well. Here, the mass effect kicks in.” [Jennie Olofsson, Sweden]

“The massive use of the masks among Albanian citizens… has become a normal well-adopted ritual of surviving, implemented as of a social significance for ‘not letting the virus in." This social cohesion on the intrapersonal view as ‘to scare the virus” and ‘fear of an enemy" comes close to a group approach of ‘control and stability." This ritual of social cohesion vis-à-vis the ‘fear of death" or ‘fear of the unknowing" is a similar to a psychological regression, when the individual survival depended largely from the herd.” [Gentian Vyshka, Albania]

“For me, unlike other measures to contain the spread of the virus, the wearing of masks is predominantly a symbol of social cohesion and complying with the rules and not so much a measure to effectively protect myself and others from infection. The few times I saw someone without a mask entering a supermarket or the metro, my first thoughts were about social deviance and the arrogance of ignoring a commonly agreed-upon practice, and not about the risk of infection.” [Mirjam Pot & Barbara Prainsack, Austria]

Individual and collective responsibility and trust in the institutions and in the official assessment of risks and recommendations as to the adopted measures are crucial to build up a degree of epistemic agreement (37). However, this is perhaps more challenging in a contested environment of “recommendation trust” (38), which likely depends on communicating certainty (39), of which very little has been seen during COVID-19 pandemic. Hence, the acceptance of official advice varied among countries, cultures, and political contexts, with some degree of contradiction.

“In general, there seems to be a relatively wide acceptance of government recommendations, but a very patchy uptake. Though the Scottish Government advice is trusted more than that from the UK Government, significant generational and cultural differences can be seen as to its implementation… in a multicultural society such as Scotland, there are some subtle differences between people from different cultural backgrounds and traditions who are either more accustomed to follow stricter government instructions, or from cultures where face mask wearing is more commonplace.” [Matjaž Vidmar, Scotland, UK]

“Finally, as an anecdote, I would mention the recent case of expelling an opposition MP from the Assembly because he did not have a mask on his face, although the Prime Minister who warned the MP did not have a mask either.” [Zoran Todorović, Serbia]

The pandemic also seems to have reminded many people about the responsibility of humanity toward the preservation of all the living organisms and, as recognized by the Centers for Disease Control and Prevention (40), that our health is closely connected to the health of whole environment.

“We should see ourselves as the most important participants and the biggest beneficiaries of public health, so we should take expert advice—wear mask. In other word, under this special situation, we need to work with medical experts, government to co-build a safe, harmonious and orderly living world with ‘One Health" concept, rather to resist or despise it.” [Bie Ying Long, China]

If we assume that in the near future we will be used to living with the pandemic, or even a series of pandemics, we are currently developing new norms for social interaction. Being with other people and enjoying their company are essential for our mental and physical well-being. How do these interactions include face mask usage? What will socializing look like in the era of physical distancing (i.e., “keeping a safe space between yourself and other people who are not from your household”) (41)? These issues are being recognized as particularly challenging.

“We must reinforce the message that face masks do not remove (or even reduce) the need for social distancing as well as excellent hand and respiratory hygiene. We need to avoid a situation where face masks become a weapon that could negatively impact our fight against this invisible enemy.” [Ciara Heavin, Ireland]

“I believe the benefits of face masks may be overestimated and lead us into a false sense of security in which we take unwarranted risks—such as touching more objects and neglecting handwashing or going outside when suffering from a cough or cold. Therefore, my preference would be to give greater attention to other steps such as providing screens and visors for workers in public facing roles and reinforcing protective mechanisms around social distancing.” [Helena Webb & Sue Ziebland, England, UK]

“Since the use of a mask started to become widespread, people seem to feel safer and unfortunately are more at risk, for example, not maintaining physical distance, making appointments with extended family and friends, etc.” [Helena Machado, Portugal]

Not all evidence is in support of above assessments that face masks bring about a (false) sense of security. In a recent study conducted in the Italian Venice metropolitan area, wearing a mask has proven to be a visual factor strengthening physical distancing as a public health measure (3). Between February 24 and April 29, 2020, distances have been measured by an operator wearing an exclusive sensor-based “social distancing belt.” They were interchangeably “unmasked,” “masked,” “do it yourself (DIY)-masked,” “goggles masked,” and “goggles DIY-masked.” Results show that people tended to stay closer to an unmasked person, while mask wearing tended to increase the physical distance. This paradox is explained by considering humans" intrinsic social nature that favors social vs. antisocial behaviors (3). Wearing a mask thus can turn unconscious social behavior into conscious antisocial behavior.

“I believe that due to the extraordinarity of wearing face coverings in public spaces in Scotland, these do not encourage an undue feeling of ‘safety" by their use, rather the reverse. Hence, with full awareness that the evidence for being protected by this measure is not there, rather, I hope that by wearing a face covering, I may remind (or even deter) others from breaking social distancing rules.” [Matjaž Vidmar, Scotland, UK]

Marchiori"s study (3) also suggests that distance increases with face mask wearing, thus supporting the importance of visual stimuli as a signal of danger. This fact recalled in the mind of our