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PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262344
Author(s):  
Maria Tsantani ◽  
Vita Podgajecka ◽  
Katie L. H. Gray ◽  
Richard Cook

The use of surgical-type face masks has become increasingly common during the COVID-19 pandemic. Recent findings suggest that it is harder to categorise the facial expressions of masked faces, than of unmasked faces. To date, studies of the effects of mask-wearing on emotion recognition have used categorisation paradigms: authors have presented facial expression stimuli and examined participants’ ability to attach the correct label (e.g., happiness, disgust). While the ability to categorise particular expressions is important, this approach overlooks the fact that expression intensity is also informative during social interaction. For example, when predicting an interactant’s future behaviour, it is useful to know whether they are slightly fearful or terrified, contented or very happy, slightly annoyed or angry. Moreover, because categorisation paradigms force observers to pick a single label to describe their percept, any additional dimensionality within observers’ interpretation is lost. In the present study, we adopted a complementary emotion-intensity rating paradigm to study the effects of mask-wearing on expression interpretation. In an online experiment with 120 participants (82 female), we investigated how the presence of face masks affects the perceived emotional profile of prototypical expressions of happiness, sadness, anger, fear, disgust, and surprise. For each of these facial expressions, we measured the perceived intensity of all six emotions. We found that the perceived intensity of intended emotions (i.e., the emotion that the actor intended to convey) was reduced by the presence of a mask for all expressions except for anger. Additionally, when viewing all expressions except surprise, masks increased the perceived intensity of non-intended emotions (i.e., emotions that the actor did not intend to convey). Intensity ratings were unaffected by presentation duration (500ms vs 3000ms), or attitudes towards mask wearing. These findings shed light on the ambiguity that arises when interpreting the facial expressions of masked faces.


2021 ◽  
Author(s):  
Aaron M Frutos ◽  
John Kubale ◽  
Guillermina Kuan ◽  
Sergio Ojeda ◽  
Nivea Vydiswaran ◽  
...  

AbstractIt has been proposed that as SARS-CoV-2 transitions to endemicity, children will represent the greatest proportion of SARS-Co-V-2 infections as they currently do with endemic coronavirus infections. While SARS-CoV-2 infection severity is low for children, it is unclear if SARS-CoV-2 infections are distinct in symptom presentation, duration, and severity from endemic coronavirus infections in children. We compared symptom risk and duration of endemic coronavirus infections from 2011-2016 with SARS-CoV-2 infections from March 2020-September 2021 in a Nicaraguan pediatric cohort. Respiratory samples were collected from participants that met testing criteria and blood samples were collected annually. Respiratory samples were tested for each of the endemic coronaviruses from 2011-2016 and for SARS-CoV-2 from 2020-2021 via rt-PCR. 2021 blood samples were tested for SARS-CoV-2 antibodies and a subset of 2011-2016 blood samples from four-years-old participants were tested for endemic coronavirus antibodies. By April 2021, 854 (49%) active participants were ELISA positive for SARS-CoV-2 antibodies. Most participants had antibodies against one alpha and one beta coronavirus by age four. We observed 595 symptomatic endemic coronavirus infections from 2011-2016 and 121 symptomatic with SARS-CoV-2 infections from March 2020-September 2021. Symptom presentation of SARS-CoV-2 infection and endemic coronavirus infections were very similar, and SARS-CoV-2 symptomatic infections were as or less severe on average than endemic coronavirus infections. This suggests that, for children, SARS-CoV-2 may be just another endemic coronavirus. However, questions about the impact of variants and the long-term effects of SARS-CoV-2 remain.


Author(s):  
Kavinda Dayasiri ◽  
Sahana Rao

Torticollis refers to a state in which the neck is twisted due to excessive contraction or shortening of the muscles on one side. Congenital muscular torticollis, which is more common than acquired torticollis, has an incidence of 0.3%–1.9% among all live births. The clinical approach to torticollis depends on the age at presentation, duration of torticollis and presenting symptoms. The underlying aetiology for torticollis varies with the age of the child. Torticollis can be a presenting feature for life-threatening conditions and thus requires careful evaluation.


2021 ◽  
pp. 174702182110533
Author(s):  
Svenja Hammerstein ◽  
Sebastian Poloczek ◽  
Patrick Lösche ◽  
Patrick Lemaire ◽  
Gerhard Büttner

Two experiments were run to determine how presentation modality and duration influence children’s arithmetic performance and strategy selection. Third and fourth graders were asked to find estimates for two-digit addition problems (e.g., 52 + 39). Children were tested in three conditions: (1) time-unlimited visual, (2) time-limited visual, or (3) time-limited auditory conditions. Moreover, we assessed children’s working-memory updating and arithmetic fluency. Children were told which strategy to use on each problem to assess arithmetic performance while executing strategies, in Experiment 1, and were asked to choose the best strategy of three available strategies to assess strategy selection, in Experiment 2. Presentation modality influenced strategy execution (i.e., children were faster and more accurate in problems under visual than auditory conditions) but only in children with low updating abilities. In contrast, presentation modality had no effect on children’s strategy selection. Presentation duration had an effect on both strategy execution and strategy selection with time-limited presentation leading to a decline in children’s performance. Interestingly, specifically in children with low updating abilities, time-limited presentation led to poorer performance. Hence, efficient updating seemed to compensate for detrimental effects of auditory in comparison to visual and time-limited in comparison to time-unlimited presentation. These findings have important implications for determining conditions under which children execute strategies most efficiently and select the best strategy on each problem most often, as well as for understanding mechanisms underlying strategic behaviour.


2021 ◽  
Author(s):  
Felix Molter ◽  
Peter N. C. Mohr

Risky choice behaviour often deviates from the predictions of normative models. The information search process has been suggested as a source of some reported "biases". Specifically, gaze-dependent evidence accumulation models, where unfixated alternatives' signals are discounted, propose a mechanistic account of observed associations between eye movements, choices and response times, with longer fixated alternatives being chosen more frequently. It remains debated, however, whether gaze causally influences the choice process, or rather reflects emerging preferences. Furthermore, other aspects the information search process, like the order in which information is inspected, can be confounded with gaze duration, complicating the identification of their causal influences. In our preregistered study 179 participants made repeated incentivized choices between two sequentially presented risky gambles, allowing the experimental control of presentation duration, order, and format (i.e., alternative-wise or attribute-wise). Across presentation formats, we find evidence against an influence of presentation duration on choice. The order in which participants were shown stimulus information, however, causally affected choices, with alternatives shown last being chosen more frequently. Notably, while gaze-dependent accumulation models generally capture effects of gaze duration, causal effects of stimulus order are only predicted by some models, identifying potential for future theory development.


2021 ◽  
pp. 53-53
Author(s):  
Shraddha Tewari ◽  
Tushar Patel ◽  
Rushi Patel ◽  
Naresh Patel

This is a study to correlate vitamin D levels in Covid positive patients admitted in GCS medical hospital, Ahmedabad .Covid 19 can vary in clinical presentation in different patients owing to their age , comorbidities and various other factors. It is now being studied whether Vitamin D levels have any bearing on initial presentation, duration of hospital stay, oxygen requirement and clinical outcome. It is a cross sectional observational study taking into account 100 patients. After applying inclusion criteria, 94 patients were selected ,out of which 37 were vitamin D decient.(39.36%). Mean vitamin D was 17.16 ±10.85 ng/ml. Out of 94 patients 55 were males and 39 were females.34% males(18) were found to be vitamin D decient and in females 51%(19)were vitamin D decient. 38% (14)of vitamin D decient people required oxygen and 48%of vitamin D decient Covid positive patients(17) required prolonged hospitalisation.


2021 ◽  
Author(s):  
Dominic McLean ◽  
Louis Renoult ◽  
George L. Malcolm

AbstractScene meaning is processed rapidly, with ‘gist’ extracted even when presentation duration spans a few dozen milliseconds. This has led some to suggest a primacy of bottom-up information. However, gist research has typically relied on showing successions of unrelated scene images, contrary to our everyday experience in which the world unfolds around us in a predictable manner. Thus, we investigated whether top-down information – in the form of observers’ predictions of an upcoming scene – facilitates gist processing. Within each trial, participants (N=336) experienced a series of images, organised to represent an approach to a destination (e.g., walking down a sidewalk), followed by a final target scene either congruous or incongruous with the expected destination (e.g., a store interior or a bedroom). Over a series of behavioural experiments, we found that: appropriate expectations facilitated gist processing; inappropriate expectations interfered with gist processing; the effect of congruency was driven by provision of contextual information rather than the thematic coherence of approach images, and; expectation-based facilitation was most apparent when destination duration was most curtailed. We then investigated the neural correlates of predictability on scene processing using ERP (N=26). Congruency-related differences were found in a putative scene-selective ERP component, related to integrating visual properties (P2), and in later components related to contextual integration including semantic and syntactic coherence (N400 and P600, respectively). Taken together, these results suggest that in real-world situations, top-down predictions of an upcoming scene influence even the earliest stages of its processing, affecting both the integration of visual properties and meaning.


2020 ◽  
Vol 73 (9) ◽  
pp. 1460-1465 ◽  
Author(s):  
Jonathan Mirault ◽  
Jonathan Grainger

The presentation duration of five-word sequences was varied and participants were asked to judge their grammaticality. The five-word sequences were presented for a variable duration randomly selected between 50 and 500 ms with 50-ms steps and were immediately followed by a masking stimulus. Half of the sequences were correct sentences which were randomly intermixed with ungrammatical sequences formed of the same words in scrambled order. We measured the proportion of correct responses for each presentation duration in the grammatical and ungrammatical conditions, and calculated sensitivity and bias from these measures. Both the sensitivity measure ( d′) and the probability correct responses to grammatical and ungrammatical sequences increased as the stimulus duration increased, with a d′ of 2 and an average percent correct close to 87% for the grammatical sequences already attained at 300 ms. The rate of increase in performance diminished beyond 300 ms. Grammatical decision times were faster and more accurate for the grammatically correct sequences, thus indicating that participants were not responding by detecting illegal word combinations in the ungrammatical sequences. On the basis of these findings, we provide an upper estimate of 300 ms as the time it takes to access reliable syntactic information from five-word sequences in French, and we discuss the implications of this constraint for models of reading.


Perception ◽  
2019 ◽  
Vol 48 (12) ◽  
pp. 1197-1213
Author(s):  
Kun Qian ◽  
Hiroyuki Mitsudo

In the eggs illusion, small patches perceptually deform when placed at the midpoints between the intersections of a regular grid. In this study, we explored the role of orientation processing in the illusion, by manipulating some spatiotemporal stimulus parameters using three psychophysical experiments. In Experiment 1, we manipulated grid luminance and presentation duration as independent variables and found that the illusion occurred even with a brief presentation of approximately 200 to 300 ms. In Experiments 2 and 3, besides presentation duration, we also systematically varied the orientation information of the stimulus. In addition to the original grid pattern, stimuli with only horizontal or vertical bars were employed in Experiment 2. The magnitude of the illusion was significantly weakened under the bar conditions. In Experiment 3, we varied the orientation of the bars stepwise and revealed that the local orientation information around the circular patches and the relative orientation information provided by the orthogonal bars of the grid are contributing factors to the illusion. Based on these results, we discussed the role of orientation processing in generating the eggs illusion.


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