99 research outputs found

    Do illiterates have illusions? A conceptual (non)replication of Luria (1976)

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    Luria (1976) famously observed that people who never learnt to read and write do not perceive visual illusions. We conducted a conceptual replication of the Luria study of the effect of literacy on the processing of visual illusions. We designed two carefully controlled experiments with 161 participants with varying literacy levels ranging from complete illiterates to high literates in Chennai, India. Accuracy and reaction time in the identification of two types of visual shape and color illusions and the identification of appropriate control images were measured. Separate statistical analyses of Experiments 1 and 2 as well as pooled analyses of both experiments do not provide any support for the notion that literacy effects the perception of visual illusions. Our large sample, carefully controlled study strongly suggests that literacy does not meaningfully affect the identification of visual illusions and raises some questions about other reports about cultural effects on illusion perception

    Does using a foreign language reduce mental imagery?

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    In a recent article, Hayakawa and Keysar (2018) propose that mental imagery is less vivid when evoked in a foreign than in a native language. The authors argue that reduced mental imagery could even account for moral foreign language effects, whereby moral choices become more utilitarian when made in a foreign language. Here we demonstrate that Hayakawa and Keysar's (2018) key results are better explained by reduced language comprehension in a foreign language than by less vivid imagery. We argue that the paradigm used in Hayakawa and Keysar (2018) does not provide a satisfactory test of reduced imagery and we discuss an alternative paradigm based on recent experimental developments

    No evidence for embodiment: The motor system is not needed to keep action words in working memory

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    Increasing evidence implicates the sensorimotor systems with high-level cognition, but the extent to which these systems play a functional role remains debated. Using an elegant design, Shebani and PulvermĆ¼ller (2013) reported that carrying out a demanding rhythmic task with the hands led to selective impairment of working memory for hand-related words (e.g., clap), while carrying out the same task with the feet led to selective memory impairment for foot-related words (e.g., kick). Such a striking double dissociation is acknowledged even by critics to constitute strong evidence for an embodied account of working memory. Here, we report on an attempt at a direct replication of this important finding. We followed a sequential sampling design and stopped data collection at N=77 (more than five times the original sample size), at which point the evidence for the lack of the critical selective interference effect was very strong (BF01 = 91). This finding constitutes strong evidence against a functional contribution of the motor system to keeping action words in working memory. Our finding fits into the larger emerging picture in the field of embodied cognition that sensorimotor simulations are neither required nor automatic in high-level cognitive processes, but that they may play a role depending on the task. Importantly, we urge researchers to engage in transparent, high-powered, and fully pre-registered experiments like the present one to ensure the field advances on a solid basis

    The Neuromodulatory and Hormonal Effects of Transcutaneous Vagus Nerve Stimulation as Evidenced by Salivary Alpha Amylase, Salivary Cortisol, Pupil Diameter, and the P3 Event-Related Potential

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    Background Transcutaneous vagus nerve stimulation (tVNS) is a new, non-invasive technique being investigated as an intervention for a variety of clinical disorders, including epilepsy and depression. It is thought to exert its therapeutic effect by increasing central norepinephrine (NE) activity, but the evidence supporting this notion is limited. Objective In order to test for an impact of tVNS on psychophysiological and hormonal indices of noradrenergic function, we applied tVNS in concert with assessment of salivary alpha amylase (SAA) and cortisol, pupil size, and electroencephalograph (EEG) recordings. Methods Across three experiments, we applied real and sham tVNS to 61 healthy participants while they performed a set of simple stimulus-discrimination tasks. Before and after the task, as well as during one break, participants provided saliva samples and had their pupil size recorded. EEG was recorded throughout the task. The target for tVNS was the cymba conchae, which is heavily innervated by the auricular branch of the vagus nerve. Sham stimulation was applied to the ear lobe. Results P3 amplitude was not affected by tVNS (Experiment 1A: Nā€Æ=ā€Æ24; Experiment 1B: Nā€Æ=ā€Æ20; Bayes factor supporting null modelā€Æ=ā€Æ4.53), nor was pupil size (Experiment 2: Nā€Æ=ā€Æ16; interaction of treatment and time: pā€Æ=ā€Æ.79). However, tVNS increased SAA (Experiments 1A and 2: Nā€Æ=ā€Æ25) and attenuated the decline of salivary cortisol compared to sham (Experiment 2: Nā€Æ=ā€Æ17), as indicated by significant interactions involving treatment and time (pā€Æ=ā€Æ.023 and pā€Æ=ā€Æ.040, respectively). Conclusion These findings suggest that tVNS modulates hormonal indices but not psychophysiological indices of noradrenergic function

    Timing of antibiotics, volume, and vasoactive infusions in children with sepsis admitted to intensive care

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    Introduction: Early administration of antibiotics for sepsis, and of fluid boluses and vasoactive agents for septic shock, is recommended. Evidence for this in children is limited. Methods: The Alberta Sepsis Network prospectively enrolled eligible children admitted to the Pediatric Intensive Care Unit (PICU) with sepsis from 04/2012-10/2014. Demographics, severity of illness, and outcomes variables were prospectively entered into the ASN database after deferred consent. Timing of interventions were determined by retrospective chart review using a study manual and case-report-form. We aimed to determine the association of intervention timing and outcome in children with sepsis. Univariate (t-test and Fisher's Exact) and multiple linear regression statistics evaluated predictors of outcomes of PICU length of stay (LOS) and ventilation days. Results: Seventy-nine children, age median 60 (IQR 22-133) months, 40 (51 %) female, 39 (49 %) with severe underlying co-morbidity, 44 (56 %) with septic shock, and median PRISM-III 10.5 [IQR 6.0-17.0] were enrolled. Most patients presented in an ED: 36 (46 %) at an outlying hospital ED, and 21 (27 %) at the Children's Hospital ED. Most infections were pneumonia with/without empyema (42, 53 %), meningitis (11, 14 %), or bacteremia (10, 13 %). The time from presentation to acceptable antibiotic administration was a median of 115.0 [IQR 59.0-323.0] minutes; 20 (25 %) of patients received their antibiotics in the first hour from presentation. Independent predictors of PICU LOS were PRISM-III, and severe underlying co-morbidity, but not time to antibiotics. In the septic shock subgroup, the volume of fluid boluses given in the first 2 hours was independently associated with longer PICU LOS (effect size 0.22 days; 95 % CI 0.5, 0.38; per ml/kg). Independent predictors of ventilator days were PRISM-III score and severe underlying co-morbidity. In the septic shock subgroup, volume of fluid boluses in the first 2 hours was independently associated with more ventilator days (effect size 0.09 days; 95 % CI 0.02, 0.15; per ml/kg). Conclusion: Higher volume of early fluid boluses in children with sepsis and septic shock was independently associated with longer PICU LOS and ventilator days. More study on the benefits and harms of fluid bolus therapy in children are needed

    Development and validation of a novel personalized electronic patient-reported outcome measure to assess quality of life (Q-LIFE): a prospective observational study in people with Cystic Fibrosis

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    Background: Generic and disease-specific patient-reported outcome measures (PROMs) may lack relevance and sensitivity on a patient-level in chronic diseases with differential disease expression and high individual variability, such as Cystic Fibrosis (CF). This study aimed to develop and validate a novel personalized electronic PROM (ePROM) that captures relevant aspects of quality of life in individuals with CF. Methods: The Q-Life app was developed as a short personalized ePROM to assess individual quality of life. Psychometric properties were assessed in a single-center cross-sectional study between September 2019 and September 2021 and in a prospective cohort study between September 2021 and September 2022. Findings: Combined studies included 223 participants (median age: 24 years, IQR: 19.0ā€“32.5 years, range: 12.0ā€“58.0 years). Internal consistency (Cronbach's alpha: 0.83ā€“0.90) and test-retest reliability (intraclass correlation coefficient: 0.90; 95% CI: 0.65ā€“0.92; p < 0.001) of quality of life (Q-Life) scores were strong. Q-Life scores were associated with overall Cystic Fibrosis Questionnaire-Revised (CFQ-R) scores (Ļ = 0.71; p < 0.001), CFQ-R respiratory domain scores (Ļ = 0.57; p < 0.001) and forced expiratory volume in 1s (Ļ = 0.41; p < 0.001). Furthermore, Q-Life scores improved from 65.0 (IQR: 45.0ā€“63.3) at baseline to 84.2 (IQR: 75.0ā€“95.0) and 87.5 (IQR: 75.0ā€“100.0) after 3 and 6 months of elexacaftor/tezacaftor/ivacaftor treatment (change: 20.8; 95% CI: 17.5ā€“25.0; p < 0.001), comparable to CFQ-R respiratory domain scores (change: 22.2, 95% CI: 19.4ā€“25.0, p < 0.001). Interpretation: The Q-Life app is a reliable, valid and sensitive personalized ePROM to measure all aspects of quality of life that really matter to individuals with Cystic Fibrosis. This patient-centered approach could provide important advantages over generic and disease-specific PROMs in the era of personalized medicine and value-based healthcare. Funding: Dutch Cystic Fibrosis Foundation, Health-Holland

    Visual Search Strategies of Soccer Players Executing a Power vs. Placement Penalty Kick

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    Introduction: When taking a soccer penalty kick, there are two distinct kicking techniques that can be adopted; a ā€˜powerā€™ penalty or a ā€˜placementā€™ penalty. The current study investigated how the type of penalty kick being taken affected the kickerā€™s visual search strategy and where the ball hit the goal (end ball location). Method: Wearing a portable eye tracker, 12 university footballers executed 2 power and placement penalty kicks, indoors, both with and without the presence of a goalkeeper. Video cameras were used to determine initial ball velocity and end ball location. Results: When taking the power penalty, the football was kicked significantly harder and more centrally in the goal compared to the placement penalty. During the power penalty, players fixated on the football for longer and more often at the goalkeeper (and by implication the middle of the goal), whereas in the placement penalty, fixated longer at the goal, specifically the edges. Findings remained consistent irrespective of goalkeeper presence. Discussion/conclusion: Findings indicate differences in visual search strategy and end ball location as a function of type of penalty kick. When taking the placement penalty, players fixated and kicked the football to the edges of the goal in an attempt to direct the ball to an area that the goalkeeper would have difficulty reaching and saving. Fixating significantly longer on the football when taking the power compared to placement penalty indicates a greater importance of obtaining visual information from the football. This can be attributed to ensuring accurate foot-to-ball contact and subsequent generation of ball velocity. Aligning gaze and kicking the football centrally in the goal when executing the power compared to placement penalty may have been a strategy to reduce the risk of kicking wide of the goal altogether
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