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Inhibitory control can be triggered directly via the retrieval of previously acquired stimulus-stop associations from memory. However, a recent study suggests that this item-specific stop learning may be mediated via expectancies of the contingencies in play (Best, Lawrence, Logan, McLaren, & Verbruggen, 2016). This could indicate that stimulus-stop learning also induces strategic proactive changes in performance. We further tested this hypothesis in the present study. In addition to measuring expectancies following task completion, we introduced a between-subjects expectancy manipulation in which one group of participants were informed about the stimulus-stop contingencies and another group did not receive any information about the stimulus-stop contingencies. Moreover, we combined this instruction manipulation with a distractor manipulation that was previously used to examine strategic proactive adjustments. We found that the stop-associated items slowed responding in both conditions. Furthermore, participants in both conditions generated expectancies following task completion that were consistent with the stimulus-stop contingencies. The distractor manipulation was ineffective. However, we found differences in the relationship between the expectancy ratings and task performance: in the instructed condition, the expectancies reliably correlated with the response slowing for the stop-associated items, whereas in the uninstructed condition we found no reliable correlation. These differences between the correlations were reliable, and our conclusions were further supported by Bayesian analyses. We conclude that stimulus-stop associations that are acquired either via task instructions or via task practice have similar effects on behaviour but could differ in how they elicit response slowing.

Event-based prospective memory (PM) involves carrying out intentions when specific events occur and is ubiquitous in everyday life. It consists of a prospective component (rememberingthatsomething must be done) and a retrospective component (rememberingwhatmust be done andwhen). Subjective sleep-related variables may be related to PM performance and an attention-demanding prospective component. In two studies, the relationship of subjective sleepiness and subjective sleep quality with both PM components was investigated with a laboratory PM task and separation of its components via Bayesian multinomial processing tree modeling. In Study 1, neither component of PM was related to naturally occurring subjective sleepiness or sleep quality. In Study 2, sleepiness was experimentally increased by placing some participants in a supine body posture. Testing participants in upright vs. supine posture affected neither PM component. However, body posture moderated the relationship between subjective sleep quality and the prospective component: In supine posture, subjective sleep quality tended to be more positively related to the prospective component. Overall, neither subjective sleepiness nor subjective sleep quality alone was related to PM.

Individual differences in semantic categorization are commonplace. Individuals apply a word like SPORTS to different instances because they employ different conditions for category membership (vagueness in criteria) or because they differ regarding the extent to which they feel the term can be applied given fixed conditions (vagueness in degree). Three individuals may, for instance, disagree as to whether chess and hiking are SPORTS, because one believes SPORTS are competitive in nature, while the other two require SPORTS to be effortful (vagueness in criteria). On the basis of whether they consider hiking sufficiently effortful or not, the latter two individuals might still disagree as to whether to call it a SPORT (vagueness in degree). We investigated whether there are systematic age-related differences in semantic categorization by analyzing the categorization decisions of 1,868 adults for eight semantic categories with a formal model that allows the two sources of categorization differences to be disentangled. We found that young and older adults assess instances differently with respect to the categorization conditions and that older adults employ a lower threshold for category membership than young adults do. We recommend that these criteria and degree differences are taken into account in studies of age-related semantic processing. ispartof: Journal of Cognition vol:2 issue:1 pages:1-20 ispartof: location:England status: published

Learning can modulate various forms of action control, including response inhibition. People may learn associations between specific stimuli and the acts of going or stopping, influencing task performance. The present study tested whether people also learn associations between specific stimuli and features of the stop or no-go signal used in the task. Across two experiments, participants performed a response-inhibition task in which the contingencies between specific stimuli and the spatial locations of the ‘go’ and ‘withhold’ signals were manipulated. The contingencies between specific stimuli and either going or withholding were also manipulated, such that a subset of stimuli were associated with responding and another subset with withholding a response. Although there was clear evidence that participants learned to associate specific stimuli with the acts of going or withholding, there was no evidence that participants acquired the spatial signal-location associations. The absence of signal learning was supported by Bayesian analyses. These findings challenge our previous proposals that learning always influences signal-detection processes in response-inhibition tasks where features of the signal remain the same throughout the task.

Collective intelligence (CI) is said to manifest in a group’s domain general mental ability. It can be measured across a battery of group IQ tests and statistically reduced to a latent factor called the “c-factor.” Advocates have found thec-factor predicts group performance better than individual IQ. We test this claim by meta-analyzing correlations between thec-factor and nine group performance criterion tasks generated by eight independent samples (N = 857 groups). Results indicated a moderate correlation,r, of .26 (95% CI .10, .40). All but four studies comprising five independent samples (N = 366 groups) failed to control for the intelligence of individual members using individual IQ scores or their statistically reduced equivalent (i.e., theg-factor). A meta-analysis of this subset of studies found the average IQ of the groups’ members had little to no correlation with group performance (r = .06, 95% CI −.08, .20). Around 80% of studies did not have enough statistical power to reliably detect correlations between the primary predictor variables and the criterion tasks. Though some of our findings are consistent with claims that a general factor of group performance may exist and relate positively to group performance, limitations suggest alternative explanations cannot be dismissed. We caution against prematurely embracing notions of thec-factor unless it can be independently and robustly replicated and demonstrated to be incrementally valid beyond theg-factor in group performance contexts.

This is a preprint. Please find the published and peer reviewed version of the paper here: https://www.journalofcognition.org/articles/10.5334/joc.80/. Images differ in their intrinsic memorability. The factors driving image memorability are not fully understood. Here, we hypothesized that memorability at least partly depends on goodness of image organization. Good organizations have been associated with fast, efficient processing and robustness against transformation (e.g., shrinking). Based on the main hypothesis, these characteristics would then also pertain to memorable images. Study 1 focused on fast processing and predicted that memorable images are easier to categorize rapidly, while Study 2 predicted that they survive a shrinking transformation better. We used real-life scene images of 14 semantic categories from a previous memorability study. Each image was assigned a “categorizability” and “shrinkability” score based on the average performance across participants on a rapid-scene categorization task (Study 1) and a thumbnail search task (Study 2), respectively. The predicted positive relation between categorizability and memorability was not observed. A post-hoc explanation attributed this null result to a masking role of image distinctiveness. In the thumbnail search task, memorable images were located faster, as predicted, but Study 2 could not rule out that this was merely a result of their distinctiveness. A third study quantified the images on distinctiveness and statistically controlled for this variable in a reanalysis of Study 1 and Study 2. When distinctiveness was controlled for, categorizability and memorability did show a significant positive correlation. Moreover, the results also argued against the alternative explanation of the results of Study 2. Taken together, the results support the hypothesis that goodness of organization contributes to image memorability.

Cognition and action are often intertwined in everyday life. It is thus pivotal to understand how cognitive processes operate with concurrent actions. The present study aims to assess how simple physical effort operationalized as isometric muscle contractions affects visual attention and inhibitory control. In a dual-task paradigm, participants performed a singleton search task and a handgrip task concurrently. In the search task, the target was a shape singleton among distractors with a homogeneous but different shape. A salient-but-irrelevant distractor with a unique color (i.e., color singleton) appeared on half of the trials (Singleton distractor present condition), and its presence often captures spatial attention. Critically, the visual search task was performed by the participants with concurrent hand grip exertion, at 5% or 40% of their maximum strength (low vs. high physical load), on a hand dynamometer. We found that visual search under physical effort is faster, but more vulnerable to distractor interference, potentially due to arousal and reduced inhibitory control, respectively. The two effects further manifest in different aspects of RT distributions that can be captured by different components of the ex-Gaussian model using hierarchical Bayesian method. Together, these results provide behavioral evidence and a novel model for two dissociable cognitive mechanisms underlying the effects of simple muscle exertion on the ongoing visual search process on a moment-by-moment basis.

In 1995, Theeuwes and Godthelp published a paper called “self-explaining roads,” in which they argued for the development of a new concept for approaching safe road design. Since this publication, self-explaining roads (SER) became one of the leading principles in road design worldwide. The underlying notion is that roads should be designed in such a way that road users immediately know how to behave and what to expect on these roads. In other words, the environment should be designed such that it elicits adequate and safe behavior. The present paper describes in detail the theoretical basis for the idea of SER and explains why this has such a large effect on human behavior. It is argued that the notion is firmly rooted in the theoretical framework of statistical learning, subjective road categorization and the associated expectations. The paper illustrates some successful implementation and describes recent developments worldwide.

Citation: Ekroll, V., Svalebjørg, M., Pirrone, A. et al. The illusion of absence: how a common feature of magic shows can explain a class of road accidents. Cogn. Research 6, 22 (2021). The purpose of the present note is to draw attention to the potential role of a recently discovered visual illusion in creating traffic accidents. The illusion consists in a compelling and immediate experience that the space behind an occluding object in the foreground is empty. Although the illusion refers to a region of space, which is invisible due to occlusion (a blind spot), there is evidence to suggest that it is nevertheless driven by visual mechanisms and that it can be just as deceptive and powerful as ordinary visual illusions. We suggest that this novel illusion can make situations involving blind spots in a road user's field of view even more dangerous than one would expect based on the lack of visibility by itself. This could be because it erroneously makes the road user feel that (s)he has actually seen everything there is to see, and thus has verified that the blind spot is empty. This hypothesis requires further testing before definitive conclusions can be drawn, but we wish to make researchers and authorities involved in the analysis of traffic accidents and on-the-spot crash investigations aware of its potential role in order to encourage registration of relevant data and facilitate further research.

AimPrevious research has focused on accuracy associated with real and fake news presented in the form of news headlines only, which does not capture the rich context news is frequently encountered in real life. Additionally, while previous studies on evaluation of real and fake news have mostly focused on characteristics of the evaluator (i.e., analytical reasoning), characteristics of the news stimuli (i.e., news source credibility) and the interplay between the two have been largely ignored. To address these research gaps, this project examined the role of analytical reasoning and news source credibility on evaluation of real and fake full-length news story articles. The project considered both accuracy and perceived credibility ratings as outcome variables, thus qualifying previous work focused solely on news detection accuracy.MethodWe conducted two independent but parallel studies, with Study 2 as a direct replication of Study 1, employing the same design but in a larger sample (Study 1:N = 292 vs. Study 2:N = 357). In both studies, participants viewed 12 full-length news articles (6 real, 6 fake), followed by prompts to evaluate each article’s veracity and credibility. Participants were randomly assigned to view articles with a credible or non-credible source and completed the Cognitive Reflection Test as well as short demographic questions.FindingsConsistent across both studies, higher analytical reasoning was associated with greater fake news accuracy, while analytical reasoning was not associated with real news accuracy. In addition, in both studies, higher analytical reasoning was associated with lower perceived credibility for fake news, while analytical reasoning was not associated with perceived credibility for real news. Furthermore, lower analytical reasoning was associated with greater accuracy for real (but not fake) news from credible compared to non-credible sources, with this effect only detected in Study 2.ConclusionsThe novel results generated in this research are discussed in light of classical vs. naturalistic accounts of decision-making as well as cognitive processes underlying news articles evaluation. The results extend previous findings that analytical reasoning contributes to fake news detection to full-length news articles. Furthermore, news-related cues such as the credibility of the news source systematically affected discrimination ability between real and fake news.

Visual inspection of luggage using X-ray technology at airports is a time-sensitive task that is often supported by automated systems to increase performance and reduce workload. The present study evaluated how time pressure and automation support influence visual search behavior and performance in a simulated luggage screening task. Moreover, we also investigated how target expectancy (i.e., targets appearing in a target-often location or not) influenced performance and visual search behavior. We used a paradigm where participants used the mouse to uncover a portion of the screen which allowed us to track how much of the stimulus participants uncovered prior to their decision. Participants were randomly assigned to either a high (5-s time per trial) or a low (10-s time per trial) time-pressure condition. In half of the trials, participants were supported by an automated diagnostic aid (85% reliability) in deciding whether a threat item was present. Moreover, within each half, in target-present trials, targets appeared in a predictable location (i.e., 70% of targets appeared in the same quadrant of the image) to investigate effects of target expectancy. The results revealed better detection performance with low time pressure and faster response times with high time pressure. There was an overall negative effect of automation support because the automation was only moderately reliable. Participants also uncovered a smaller amount of the stimulus under high time pressure in target-absent trials. Target expectancy of target location improved accuracy, speed, and the amount of uncovered space needed for the search. Significance Statement Luggage screening is a safety–critical real-world visual search task which often has to be done under time pressure. The present research found that time pressure compromises performance and increases the risk to miss critical items even with automation support. Moreover, even highly reliable automated support may not improve performance if it does not exceed the manual capabilities of the human screener. Lastly, the present research also showed that heuristic search strategies (e.g., areas where targets appear more often) seem to guide attention also in luggage screening.

We investigated the effect of expertise on the wisdom of crowds. Participants completed 60 trials of a numerical estimation task, during which they saw 50–100 asterisks and were asked to estimate how many stars they had just seen. Experiment 1 established that both inner- and outer-crowd wisdom extended to our novel task: Single responses alone were less accurate than responses aggregated across a single participant (showing inner-crowd wisdom) and responses aggregated across different participants were even more accurate (showing outer-crowd wisdom). In Experiment 2, prior to beginning the critical trials, participants did 12 practice trials with feedback, which greatly increased their accuracy. There was a benefit of outer-crowd wisdom relative to a single estimate. There was no inner-crowd wisdom effect, however; with high accuracy came highly restricted variance, and aggregating insufficiently varying responses is not beneficial. Our data suggest that experts give almost the same answer every time they are asked and so they should consult the outer crowd rather than solicit multiple estimates from themselves.

The aim of this study was to examine the impact of predictability on dual-task performance by systematically manipulating predictability in either one of two tasks, as well as between tasks. According to capacity-sharing accounts of multitasking, assuming a general pool of resources two tasks can draw upon, predictability should reduce the need for resources and allow more resources to be used by the other task. However, it is currently not well understood what drives resource-allocation policy in dual tasks and which resource allocation policies participants pursue. We used a continuous tracking task together with an audiomotor task and manipulated advance visual information about the tracking path in the first experiment and a sound sequence in the second experiments (2a/b). Results show that performance predominantly improved in the predictable task but not in the unpredictable task, suggesting that participants did not invest more resources into the unpredictable task. One possible explanation was that the re-investment of resources into another task requires some relationship between the tasks. Therefore, in the third experiment, we covaried the two tasks by having sounds 250 ms before turning points in the tracking curve. This enabled participants to improve performance in both tasks, suggesting that resources were shared better between tasks.

People with visual impairment often rely on their residual vision when interacting with their spatial environments. The goal of visual accessibility is to design spaces that allow for safe travel for the large and growing population of people who have uncorrectable vision loss, enabling full participation in modern society. This paper defines the functional challenges in perception and spatial cognition with restricted visual information and reviews a body of empirical work on low vision perception of spaces on both local and global navigational scales. We evaluate how the results of this work can provide insights into the complex problem that architects face in the design of visually accessible spaces.

Past research suggests that an uncritical or ‘lazy’ style of evaluating evidence may play a role in the development and maintenance of implausible beliefs. We examine this possibility by using a quasi-experimental design to compare how low- and high-quality evidence is evaluated by those who do and do not endorse implausible claims. Seven studies conducted during 2019–2020 provided the data for this analysis (N = 746). Each of the seven primary studies presented participants with high- and/or low-quality evidence and measured implausible claim endorsement and evaluations of evidence persuasiveness (via credibility, value, and/or weight). A linear mixed-effect model was used to predict persuasiveness from the interaction between implausible claim endorsement and evidence quality. Our results showed that endorsers were significantly more persuaded by the evidence than non-endorsers, but both groups were significantly more persuaded by high-quality than low-quality evidence. The interaction between endorsement and evidence quality was not significant. These results suggest that the formation and maintenance of implausible beliefs by endorsers may result from less critical evidence evaluations rather than a failure to analyse. This is consistent with a limited rather than a lazy approach and suggests that interventions to develop analytical skill may be useful for minimising the effects of implausible claims.

Misinformation often has an ongoing effect on people’s memory and inferential reasoning even after clear corrections are provided; this is known as the continued influence effect. In pursuit of more effective corrections, one factor that has not yet been investigated systematically is the narrative versus non-narrative format of the correction. Some scholars have suggested that a narrative format facilitates comprehension and retention of complex information and may serve to overcome resistance to worldview-dissonant corrections. It is, therefore, a possibility that misinformation corrections are more effective if they are presented in a narrative format versus a non-narrative format. The present study tests this possibility. We designed corrections that are either narrative or non-narrative, while minimizing differences in informativeness. We compared narrative and non-narrative corrections in three preregistered experiments (totalN = 2279). Experiment 1 targeted misinformation contained in fictional event reports; Experiment 2 used false claims commonly encountered in the real world; Experiment 3 used real-world false claims that are controversial, in order to test the notion that a narrative format may facilitate corrective updating primarily when it serves to reduce resistance to correction. In all experiments, we also manipulated test delay (immediate vs. 2 days), as any potential benefit of the narrative format may only arise in the short term (if the story format aids primarily with initial comprehension and updating of the relevant mental model) or after a delay (if the story format aids primarily with later correction retrieval). In all three experiments, it was found that narrative corrections are no more effective than non-narrative corrections. Therefore, while stories and anecdotes can be powerful, there is no fundamental benefit of using a narrative format when debunking misinformation.

There is evidence that already in Greco-Roman times, fish with electrical properties were placed on people's heads to relieve certain ailments, such as migraine or mood disorders. Since then, the use of electrical current as a treatment for pathological conditions or deficiencies has been progressively refined towards the development of a safe, effective, and standardized technique that modulates brain functioning. Here we address the basic principles of transcranial electrical stimulation and its use in the modulation of cognitive processes as relevant as attention.

The illusory truth effect occurs when the repetition of a claim increases its perceived truth. Previous studies have demonstrated the illusory truth effect with true and false news headlines. The present study examined the effects that different ratings made during initial exposure have on the illusory truth effect with news headlines. In two experiments, participants (total N = 575) rated a set of news headlines in one of two conditions. Some participants rated how interesting they were, and others rated how truthful they were. Participants later rated the perceived accuracy of a larger set of headlines that included previously rated and new headlines. In both experiments, prior exposure increased perceived accuracy for participants who made initial interest ratings, but not for participants who made initial truthfulness ratings. The increase in perceived accuracy that accompanies repeated exposure was attenuated when participants considered the accuracy of the headlines at initial exposure. Experiment 2 also found evidence for a political bias: participants rated politically concordant headlines as more accurate than politically discordant headlines. The magnitude of this bias was related to performance on a cognitive reflection test; more analytic participants demonstrated greater political bias. These results highlight challenges that fake news presents and suggest that initially encoding headlines’ perceived truth can serve to combat the illusion that a familiar headline is a truthful one.

To better understand the spread of fake news in the Internet age, it is important to uncover the variables that influence the perceived truth of information. Although previous research identified several reliable predictors of truth judgments—such as source credibility, repeated information exposure, and presentation format—little is known about their simultaneous effects. In a series of four experiments, we investigated how the abovementioned factors jointly affect the perceived truth of statements (Experiments 1 and 2) and simulated social media postings (Experiments 3 and 4). Experiment 1 explored the role of source credibility (high vs. low vs. no source information) and presentation format (with vs. without a picture). In Experiments 2 and 3, we additionally manipulated repeated exposure (yes vs. no). Finally, Experiment 4 examined the role of source credibility (high vs. low) and type of repetition (congruent vs. incongruent vs. no repetition) in further detail. In sum, we found no effect of presentation format on truth judgments, but strong, additive effects of source credibility and repetition. Truth judgments were higher for information presented by credible sources than non-credible sources and information without sources. Moreover, congruent (i.e., verbatim) repetition increased perceived truth whereas semantically incongruent repetition decreased perceived truth, irrespectively of the source. Our findings show that people do not rely on a single judgment cue when evaluating a statement’s truth but take source credibility and their meta-cognitive feelings into account.

The “surprisingly popular” method (SP) of aggregating individual judgments has shown promise in overcoming a weakness of other crowdsourcing methods—situations in which the majority is incorrect. This method relies on participants’ estimates of other participants’ judgments; when an option is chosen more often than the average metacognitive judgments of that option, it is “surprisingly popular” and is selected by the method. Although SP has been shown to improve group decision making about factual propositions (e.g., state capitals), its application to future outcomes has been limited. In three preregistered studies, we compared SP to other methods of aggregating individual predictions about future events. Study 1 examined predictions of football games, Study 2 examined predictions of the 2018 US midterm elections, and Study 3 examined predictions of basketball games. When applied to judgments made by objectively assessed experts, SP performed slightly better than other aggregation methods. Although there is still more to learn about the conditions under which SP is effective, it shows promise as a means of crowdsourcing predictions of future outcomes.

Existe evidencia de que en tiempos tan remotos como la antigüedad greco-romana se colocaban peces con propiedades eléctricas sobre la cabeza de personas con el fin de aliviar ciertas dolencias, como la migraña o alteraciones del estado anímico. Desde entonces el empleo de la corriente eléctrica para tratar estados patológicos o deficiencias se ha refinado progresivamente hasta el desarrollo de una técnica protocolizada, segura y eficaz, para modular el funcionamiento cerebral. Aquí abordamos los principios básicos de la estimulación eléctrica transcraneal y su uso en la modulación de procesos cognitivos tan relevantes como la atención.

The last few years have seen a rapid growth of interest amongst researchers in the crossmodal correspondences. One of the correspondences that has long intrigued artists is the putative association between colours and odours. While traditionally conceptualised in terms of synaesthesia, over the last quarter century or so, at least 20 published peer-reviewed articles have assessed the consistent, and non-random, nature of the colours that people intuitively associate with specific (both familiar and unfamiliar) odours in a non-food context. Having demonstrated such consistent mappings amongst the general (i.e. non-synaesthetic) population, researchers have now started to investigate whether they are shared cross-culturally, and to document their developmental acquisition. Over the years, several different explanations have been put forward by researchers for the existence of crossmodal correspondences, including the statistical, semantic, structural, and emotional-mediation accounts. While several of these approaches would appear to have some explanatory validity as far as the odour-colour correspondences are concerned, contemporary researchers have focussed on learned associations as the dominant explanatory framework. The nature of the colour-odour associations that have been reported to date appear to depend on the familiarity of the odour and the ease of source naming, and hence the kind of association/representation that is accessed. While the bidirectionality of odour-colour correspondences has not yet been rigorously assessed, many designers are nevertheless already starting to build on odour-colour crossmodal correspondences in their packaging/labelling/branding work.

Stimulasi pada anak usia dini perlu dilakukan secara seimbang sesuai tahap perkembangannya. Salah satu aspek yang perlu distimulasi adalah aspek perkembangan emosi. Akan tetapi, guru maupun orang tua anak usia dini seringkali merasa kesulitan memberikan stimulasi perkembangan emosi. Penelitian ini bertujuan untuk meningkatkan keterampilan stimulasi perkembangan emosi pada guru PAUD melalui aktivitas storytelling. Aktivitas storytelling dilakukan dalam kelompok kecil sesuai usia dan dipandu oleh guru sebagai fasilitator. Melalui aktivitas ini, guru dapat mengenalkan berbagai emosi dasar, mengajari anak untuk mengenali respons fisiologis yang mengikuti munculnya emosi, serta mendorong anak menggali pengalaman pribadi yang memunculkan respons emosi tertentu.

Various studies have been done to overcome excessive fear of heights. One way to overcome excessive fear of heights is to use exposure therapy. This study aimed to determine the effect of virtual reality heights exposure on physiological response and emotional condition in college students. The hypothesis of this study was that there is a significant effect of virtual reality heights exposure on physiological response and emotional condition that is characterized by changes in skin conductance when the stimulus is presented and changes in emotional condition after the stimulus is presented. The design applied in this study was a non-random pretest and posttest experiment. The results of this study indicated that there is a significant influence of virtual reality exposure on physiological response and emotional condition. Thus, the finding opens up opportunities for therapy using this method in Indonesia.

Performa bermatematika anak-anak Indonesia, dilaporkan jauh di bawah dari harapan. Terdapat indikasi bahwa fungsi eksekutif berperan dalam performa dan prestasi matematika. Penelitian ini bertujuan menguji efektivitas penggunaan training terkomputerisasi yang mengadopsi paradigma pengukuran fungsi eksekutif, untuk mendongkrak performa bermatematika. Paradigma tugas seperti n-back task, flanker task, go no/go task, numerical-estimation task, dan stroop task, dirangkai menjadi suatu latihan melalui aplikasi OpenSesame®. Kelompok eksperimen (n=32), diberikan 45 menit training selama tujuh hari, dan diberikan tes matematika pada pre dan posttest. Kemudian, dibandingkan dengan kelompok kontrol (n=34) yang juga diberikan pretest dan posttest tanpa diberi perlakuan apapun. Hasil pengujian menunjukkan perbedaan rerata yang signifikan (t=-5,04; p0,05). Hasil uji ANAVA terhadap skor kapasitas fungsi eksekutif setiap sesi menunjukkan perbedaan signifikan (F=13,47; p

Background The wisdom of crowds and collective decision-making are important tools for integrating information between individuals, which can exceed the capacity of individual judgments. They are based on different forms of information integration. The wisdom of crowds refers to the aggregation of many independent judgments without deliberation and consensus, while collective decision-making is aggregation with deliberation and consensus. Recent research has shown that collective decision-making outperforms the wisdom of crowds. Additionally, many studies have shown that metacognitive knowledge of subjective confidence is useful for improving aggregation performance. However, because most of these studies have employed relatively simple problems; for example, involving general knowledge and estimating values and quantities of objects, it remains unclear whether their findings can be generalized to real-life situations involving complex information integration. This study explores the performance and process of the wisdom of crowds and collective decision-making by applying the wisdom of crowds with weighted confidence to a survival situation task commonly used in studies of collective decision-making. Results The wisdom of crowds and collective decision-making outperformed individual judgment. However, collective decision-making did not outperform the wisdom of crowds. Contrary to previous studies, weighted confidence showed no advantage from comparison between confidence-weighted and non-weighted aggregations; a simulation analysis varying in group size and sensitivity of confidence weighting revealed interaction between group size and sensitivity of confidence weighting. This reveals that it is because of small group size and not the peculiarity of the survival task that results in no advantage of weighted confidence. Conclusions The study’s findings suggest that the wisdom of crowds could be applicable to complex problem-solving tasks, and interaction between group size and sensitivity of confidence weighting is important for confidence-weighted aggregation effects.

Las letras son estímulos visuales especiales. Inmersas en palabras, nos cuesta mucho distinguir “cedro” de “cerdo”, lo cual se conoce como efecto de transposición. Este efecto sucede en menor grado con secuencias de dígitos o símbolos. ¿Cuándo comienzan las letras a tener ese estatus especial? En un experimento reciente de nuestro laboratorio demostramos que seis días de práctica intensiva no son suficientes, pero ya permiten vislumbrar los inicios de un procesamiento especial de las letras.

Los olvidos en la toma de los fármacos prescritos por los médicos pueden tener consecuencias graves para la salud y la calidad de vida de las personas. En el mercado se pueden encontrar múltiples instrumentos que intentan ayudar en la lucha contra estos olvidos (dispositivos de alarma, pastilleros inteligentes, aplicaciones informáticas…), pero su eficacia no está completamente demostrada y su costo, a menudo, es elevado. Estudios recientes apoyan la eficacia de estrategias psicológicas como el Procedimiento de Consecuencias Diferenciales cuando el número de asociaciones a recordar supera los límites de la memoria de trabajo.

Ser capaces de frenar impulsos que son inadecuados en un momento dado es una habilidad esencial en nuestras vidas. Esta habilidad se ha estudiado fundamentalmente en contextos simples que requieren inhibir una única respuesta ante un único estímulo. Sin embargo, en nuestro día a día es frecuente que tengamos que enfrentarnos a situaciones que requieren inhibir nuestras acciones ante unos estímulos, pero no ante otros. En este artículo presentamos los resultados de recientes estudios conductuales, cerebrales y genéticos sobre este tipo de inhibición, denominada selectiva, que nos ayudan a comprenderla y que abren la puerta a nuevas investigaciones.

It has widely been accepted that aggregating group-level decisions is superior to individual decisions. As compared to individuals, groups tend to show a decision advantage in their response accuracy. However, there has been a lack of research exploring whether group decisions are more efficient than individual decisions with a faster information-processing speed. To investigate the relationship between accuracy and response time (RT) in group decision-making, we applied systems’ factorial technology, developed by Townsend and Nozawa (Journal of Mathematical Psychology 39, 321–359, 1995) and regarded as a theory-driven methodology, to study the information-processing properties. More specifically, we measured the workload capacity CAND(t), which only considers the correct responses, and the assessment function of capacity AAND(t), which considers the speed-accuracy trade-off, to make a strong inference about the system-level processing efficiency. A two-interval, forced-choice oddball detection task, where participants had to detect which interval contains an odd target, was conducted in Experiment 1. Then, in Experiment 2, a yes/no Gabor detection task was adopted, where participants had to detect the presence of a Gabor patch. Our results replicated previous findings using the accuracy-based measure: Group detection sensitivity was better than the detection sensitivity of the best individual, especially when the two individuals had similar detection sensitivities. On the other hand, both workload capacity measures, CAND(t) and AAND(t), showed evidence of supercapacity processing, thus suggesting a collective benefit. The ordered relationship between accuracy-based and RT-based collective benefit was limited to the AAND(t) of the correct and fast responses, which may help uncover the processing mechanism behind collective benefits. Our results suggested that AAND(t), which combines both accuracy and RT into inferences, can be regarded as a novel and diagnostic tool for studying the group decision-making process.

Schizophrenia is associated with a number of deficits in decision-making, but the scope, nature, and cause of these deficits are not completely understood. Here we focus on a particular type of decision, known as the explore/ exploit dilemma, in which people must choose between exploiting options that yield relatively known rewards and exploring more ambiguous options of uncertain reward probability or magnitude. Previous work has shown that healthy people use two distinct strategies to decide when to explore: directed exploration, which involves choosing options that would reduce uncertainty about the reward values (information seeking), and random exploration (exploring by chance), which describes behavioral variability that is not goal directed. We administered a recently developed gambling task designed to quantify both directed and random exploration to 108 patients with schizophrenia (PSZ) and 33 healthy volunteers (HVs). We found that PSZ patients show reduced directed exploration relative to HVs, but no difference in random exploration. Moreover, patients’ directed exploration behavior clusters into two qualitatively different behavioral phenotypes. In the first phenotype, which accounts for the majority of the patients (79%) and is consistent with previously reported behavior, directed exploration is only marginally (but significantly) reduced, suggesting that these patients can use directed exploration, but at a slightly lower level than community controls. In contrast, the second phenotype, comprising 21% of patients, exhibits a form of “extreme ambiguity aversion,” in which they almost never choose more informative options, even when they are clearly of higher value. Moreover, in PSZ, deficits in directed exploration were related to measures of intellectual function, whereas random exploration was related to positive symptoms. Taken together, our results suggest that schizophrenia has differential effects on directed and random exploration and that investigating the explore/exploit dilemma in psychosis patients may reveal subgroups of patients with qualitatively different patterns of exploration.

Most everyday activities involve delayed intentions referring to different event structures and timelines. Yet, past research has mostly considered prospective memory (PM) as a dual-task phenomenon in which the primary task to fulfill PM intentions is realized within an ongoing secondary task. We hypothesized that these simplified simulations of PM may have obscured the role of spatial relational processing that is functional to represent and meet the increased temporal demands in more complex PM scenarios involving multiple timelines. To test this spatiotemporal hypothesis, participants monitored four digital clocks, with PM deadlines referring either to the same clock (single-context condition) or different clocks (multiple-context condition), along with separate tests of spatial ability (mental rotation task) and executive functioning (working memory updating). We found that performance in the mental rotation task incrementally explained PM performance in the multiple-context, but not in the single-context, condition, even after controlling for individual differences in working memory updating and ongoing task performance. These findings suggest that delayed intentions occurring in multiple ongoing task contexts reflect independent contributions of working memory updating and mental rotation and that spatial relational processing may specifically be involved in higher cognitive functions, such as complex PM in multiple contexts or multitasking.

Debate regarding the best way to test and measure eyewitness memory has dominated the eyewitness literature for more than 30 years. We argue that resolution of this debate requires the development and application of appropriate measurement models. In this study we developed models of simultaneous and sequential lineup presentations and used these to compare these procedures in terms of underlying discriminability and response bias, thereby testing a key prediction of diagnostic feature detection theory, that underlying discriminability should be greater for simultaneous than for stopping-rule sequential lineups. We fit the models to the corpus of studies originally described by Palmer and Brewer (2012, Law and Human Behavior, 36(3), 247–255), to data from a new experiment and to eight recent studies comparing simultaneous and sequential lineups. We found that although responses tended to be more conservative for sequential lineups there was little or no difference in underlying discriminability between the two procedures. We discuss the implications of these results for the diagnostic feature detection theory and other kinds of sequential lineups used in current jurisdictions.

According to the influential “Two Visual Pathways” hypothesis, the cortical visual system is segregated into two pathways, with the ventral, occipitotemporal pathway subserving object perception, and the dorsal, occipitoparietal pathway subserving the visuomotor control of action. However, growing evidence suggests that the dorsal pathway also plays a functional role in object perception. In the current article, we present evidence that the dorsal pathway contributes uniquely to the perception of a range of visuospatial attributes that are not redundant with representations in ventral cortex. We describe how dorsal cortex is recruited automatically during perception, even when no explicit visuomotor response is required. Importantly, we propose that dorsal cortex may selectively process visual attributes that can inform the perception of potential actions on objects and environments, and we consider plausible developmental and cognitive mechanisms that might give rise to these representations. As such, we consider whether naturalistic stimuli, such as real-world solid objects, might engage dorsal cortex more so than simplified or artificial stimuli such as images that do not afford action, and how the use of suboptimal stimuli might limit our understanding of the functional contribution of dorsal cortex to visual perception.

¿Mejora la meditación mindfulness la capacidad de dirigir nuestra atención y acciones de forma flexible y eficaz hacia metas relevantes? Describimos a continuación el primer metaanálisis que examina la eficacia del entrenamiento en meditación mindfulness en la mejora del control ejecutivo. El estudio sintetiza un total de 13 ensayos controlados aleatorizados llevados a cabo en población adulta, en los que el rendimiento en esta función cognitiva se evaluó a través de pruebas neuropsicológicas y tareas cognitivas informatizadas. Los resultados del metaanálisis indican que la práctica de meditación mindfulness ejerce una mejora modesta, pero consistente, del control ejecutivo.

Languages differ qualitatively in their numeral systems. At one extreme, some languages have a small set of number terms, which denote approximate or inexact numerosities; at the other extreme, many languages have forms for exact numerosities over a very large range, through a recursively defined counting system. Why do numeral systems vary as they do? Here, we use computational analyses to explore the numeral systems of 30 languages that span this spectrum. We find that these numeral systems all reflect a functional need for efficient communication, mirroring existing arguments in other semantic domains such as color, kinship, and space. Our findings suggest that cross-language variation in numeral systems may be understood in terms of a shared functional need to communicate precisely while using minimal cognitive resources.

Background In criminal investigations, uncooperative witnesses might deny knowing a perpetrator, the location of a murder scene or knowledge of a weapon. We sought to identify markers of recognition in eye fixations and confidence judgments whilst participants told the truth and lied about recognising faces (Experiment 1) and scenes and objects (Experiment 2) that varied in familiarity. To detect recognition we calculated effect size differences in markers of recognition between familiar and unfamiliar items that varied in familiarity (personally familiar, newly learned). Results In Experiment 1, recognition of personally familiar faces was reliably detected across multiple fixation markers (e.g. fewer fixations, fewer interest areas viewed, fewer return fixations) during honest and concealed recognition. In Experiment 2, recognition of personally familiar non-face items (scenes and objects) was detected solely by fewer fixations during honest and concealed recognition; differences in other fixation measures were not consistent. In both experiments, fewer fixations exposed concealed recognition of newly learned faces, scenes and objects, but the same pattern was not observed during honest recognition. Confidence ratings were higher for recognition of personally familiar faces than for unfamiliar faces. Conclusions Robust memories of personally familiar faces were detected in patterns of fixations and confidence ratings, irrespective of task demands required to conceal recognition. Crucially, we demonstrate that newly learned faces should not be used as a proxy for real-world familiarity, and that conclusions should not be generalised across different types of familiarity or stimulus class.

Teachers sometimes believe in the efficacy of instructional practices that have little empirical support. These beliefs have proven difficult to efface despite strong challenges to their evidentiary basis. Teachers typically develop causal beliefs about the efficacy of instructional practices by inferring their effect on students’ academic performance. Here, we evaluate whether causal inferences about instructional practices are susceptible to an outcome density effect using a contingency learning task. In a series of six experiments, participants were ostensibly presented with students’ assessment outcomes, some of whom had supposedly received teaching via a novel technique and some of whom supposedly received ordinary instruction. The distributions of the assessment outcomes was manipulated to either have frequent positive outcomes (high outcome density condition) or infrequent positive outcomes (low outcome density condition). For both continuous and categorical assessment outcomes, participants in the high outcome density condition rated the novel instructional technique as effective, despite the fact that it either had no effect or had a negative effect on outcomes, while the participants in the low outcome density condition did not. These results suggest that when base rates of performance are high, participants may be particularly susceptible to drawing inaccurate inferences about the efficacy of instructional practices.

BackgroundSpatial thinking skills are strongly correlated with achievement in Science, Technology, Engineering, and Mathematics (STEM) fields and emerging research suggests that interventions aimed at building students’ skills will likely yield measurable impacts on learning across K-12 settings. The importance of spatial thinking in science has received increased attention in academic discussions; however, the intentional practice of teaching spatial thinking skills is still largely absent from K-12 education. The translation of science into educational practice is challenging for a variety of reasons, including the difficulty “translating” research findings into practical applications and limited resources to support its development, implementation, and evaluation. Given these obstacles, one may ask “can spatial thinking be brought to the classroom?” In this paper, we argue that in order to effectively move research into the classroom, we must first systematically explorehowspatial thinking can be translated into practice.ApproachWe present a use-inspired, integrative framework that draws upon planned action and translation science theories, as well as research from cognitive, developmental, educational, and implementation sciences, to guide the infusion of spatial thinking into science curricula. In theKnowledge Translation Framework(KTF), translation is conceived as a multistage process, proceeding through seven stages: (1) the identification of relevant disciplinary and contextual knowledge, (2) the synthesis and translation of knowledge into guidelines to support the infusion of knowledge into the curriculum, (3) the development of tools to support curriculum development, implementation, and track the translation process, (4) the iterative development and refinement of the spatially-enhanced curriculum, (5) the creation of an analysis plan to evaluate the impact of the spatial enhancements and other contextual features on learning, (6) the development and implementation of an intervention plan, and (7) the evaluation of the intervention.ConclusionThe KTF is a use-inspired, integrative framework that unpacks the translation process and offers practical guidance on how a team may synthesize scientific and contextual knowledge, infuse it into a curriculum, and evaluate its impact in ways that will yield scientific understandingandpractical knowledge. We also provide illustrative examples of how this approach was used to spatially enhance an elementary science curriculum.

Background This study investigated the impact of handedness on a common spatial abilities task, the mental rotation task (MRT). The influence of a right-handed world was contrasted with people’s embodied experience with their own hands by testing both left- and right-handed people on an MRT of right- and left-hand stimuli. An additional consideration is the influence of matching the shape of the hand stimuli with the proprioception of one’s own hands. Two orthogonal hypothesis axes were crossed to yield four competing hypotheses. One axis contrasted (i) embodied experience versus (ii) world knowledge; the other axis contrasted (a) the match between the visual image of a hand on the screen and one’s own hand versus (b) the resemblance of the shape outline information from the hand stimuli with the proprioception of one’s own hands. Results Among people with mixed handedness, right-handers performed more accurately for left-hand stimuli, while left-handers had a trend for higher accuracy for right-hand stimuli. For people with extreme handedness, right-handers outperformed left-handers. Regardless of group, there was no significant variation in performance for left-hand stimuli, with only right-hand stimuli producing significant variation. Conclusions No hypothesis fully aligned with all the data. For left-hand stimuli, the consistent performance across groups does not provide support for embodied experience, while world knowledge might influence all groups similarly. Alternatively, the within-group variation for mixed-handed people supports embodied experience in the hand MRT, likely processed through visual-proprioceptive integration.

Los niños víctimas de maltrato con frecuencia tienen problemas a la hora de lidiar con las emociones negativas y a menudo desarrollan enfermedades psiquiátricas, entre las que se incluye el trastorno de estrés postraumático complejo (TEPC). Estudios recientes muestran que estos niños prestan atención a caras que expresan alegría, tristeza o amenaza de un modo diferente a como lo hacen los niños que no sufren maltrato. Tales sesgos atencionales parecen, además, estar relacionados con la posterior aparición de problemas clínicos y sociales, lo que sugiere que intentemos intervenir sobre ellos.

Stres akademik menjadi permasalahan yang banyak terjadi pada mahasiswa. Berbagai penyesuaian yang harus dihadapinya dalam peran dan lingkungan barunya tersebut kerapkali menjadi stressor tersendiri, terlebih bagi mahasiswa yang tidak memiliki kemampuan koping yang adaptif. Penelitian ini bertujuan untuk melihat pengaruh program pelatihan strategi koping fokus emosi untuk menurunkan tingkat stres akademik pada mahasiswa. Desain studi menggunakan metode eksperimen quasi dengan one group pretest–posttest design . Subjek dalam penelitian berjumlah 16 mahasiswa ( M =19,81 tahun; SD =0,911) dari salah satu perguruan tinggi di Yogyakarta, Indonesia. Instrumen pengukuran yang digunakan meliputi Skala Koping Fokus Emosi dan Skala Stres Akademik. Analisis statistik paired sample t-test menunjukkan bahwa pelatihan strategi koping fokus emosi terbukti dapat menurunkan stres akademik pada mahasiswa dengan t (15)=2,149; p =0,048 ( p

Basic cognitive research can help to explain our response to wine, and the myriad factors that affect it. Wine is a complex, culture-laden, multisensory stimulus, and our perception/experience of its properties is influenced by everything from the packaging in which it is presented through the glassware in which it is served and evaluated. A growing body of experiential wine research now demonstrates that a number of contextual factors, including everything from the colour of the ambient lighting through to background music can exert a profound, and in some cases predictable, influence over the tasting experience. Sonic seasoning - that is, the matching of music or soundscapes with specific wines in order to accentuate or draw attention to certain qualities/attributes in the wine, such as sweetness, length, or body, also represents a rapidly growing area of empirical study. While such multisensory, experiential wine research undoubtedly has a number of practical applications, it also provides insights concerning multisensory perception that are relevant to basic scientists. Furthermore, the findings of the wine research are also often relevant to those marketers interested in understanding how the consumers’ perception of any other food or beverage product can potentially be modified.

Persepsi masyarakat tentang narapidana memberikan efek yang buruk terhadap persepsi narapidana tentang diri mereka sehingga tahanan anak merasa rendah diri menghadapi penerimaan masyarakat setelah masa hukuman berakhir. Penelitian ini menggunakan Program AKTIF (Aku Positif) yang bertujuan untuk meningkatkan harga diri remaja yang berhadapan dengan hukum menjelang masa bebas. Desain yang digunakan dalam penelitian ini adalah untreated control group design with dependent pretest and posttest samples. Analisis data yang digunakan dalam penelitian ini adalah uji statistik non parametrik Wilcoxon. Subjek penelitian berjumlah 12 orang remaja yang sedang menjalani masa tahanan (usia 16-18 tahun). Hasil penelitian menunjukkan bahwa terdapat peningkatan skor self-esteem lebih tinggi U(n=6)=0,027, p

Objective: to compare mountaineers with and without asymptomatic sleep apnea (OSA) before the ascent and to study high altitude-related sleep disorders, its interaction with metabolic, neuroendocrine and immunological components. Material and Methods: During an expedition to Mount Aconcagua, researchers assessed the respiratory polygraphy (RP), clinical condition and inflammatory parameters, and rhythm of cortisol secretion in mountaineers sleeping at different altitude camps. Results: 8 athletes (4 women), 36 years old (25-51) participated. Baseline and final BMI were; 23.6 (20.9-28.7) and 22.77 (20.9-27.7), respectively: p

Introduction: There are still many gaps in research concerning the effect of different physical training modalities on sleep quality in the population underwent coronary artery bypass graft (CABG) surgeries. Objective: The purpose of this study was to compare the effect of different exercise types on sleep quality and functional capacity after CABG. Material and Methods: 80 Participants aged 45-65 years were randomized to two groups: aerobic group (AG), and combined aerobic and resistance group (ARG). Training lasted ten consecutive weeks with 30 uninterrupted sessions. The actigraph together with Pittsburg Sleep Quality Index (PSQI) were used in sleep quality assessment. Six-minute walk test (6MWT) was used in assessment of functional capacity. The actigraph (Actiwatch Minimitter Company, Incorporated (INC) - Sunriver, OR, USA) was placed on the non-dominant wrist and activities were monitored continuously while being recorded at one-minute intervals. The participants kept the device for a period of 96 hours, filled PSQI, and did 6MWT before the first and last training sessions. Results: There was significant decrease in the mean value of sleep latency, fragmentation index, light sleep duration and sleep quality scores (p

Background Social media is an increasingly popular outlet for leisure and social interaction. On many social media platforms, the user experience involves commenting on or responding to user-generated content, such as images of cats, food, and people. In two experiments, we examined how the act of commenting on social media images impacts subsequent memory of those images, using Instagram posts as a test case. This project was inspired by recent findings of laboratory studies of conversation which found that describing a picture for a conversational partner boosts recognition memory for those images. Here we aimed to understand how this finding translates to the more ecologically valid realm of social media interactions. A second motivation for the study was the popularity of food- and dieting-related content on Instagram and prior findings that use of Instagram in particular is associated with disordered eating behaviors. Results Across two experiments, we observed that commenting on Instagram posts consistently boosted subsequent recognition and that correct recognition increased with comment length. Stable individual differences in recognition memory were observed, and “unhealthy” food images such as chocolates were particularly well remembered; however, these memory findings did not relate to self-reported eating behavior. Conclusions Taken together, our findings show that the way in which we engage with social media content shapes subsequent memory of it, raising new questions about how our online lives persist in memory over time, potentially shaping future behavior.

Background: Little is known on sleep quality of children with atopic dermatitis (AD) during flares and how treatment impacts their sleep. The purpose of this study is to evaluate variations in sleep quality of children with AD during flares and its response to intensified treatment. Material and Methods: Prospective case-crossover study in 10 children with moderate-severe AD. At baseline, AD severity was assessed using SCORAD and patients were prescribed intensified AD therapy. All subjects were monitored by actigraphy during 14 days and returned for SCORAD assessment. Results: Subjects’ age was 5.6 ± 5.3 years; 50% were female. Sleep duration was decreased in all subjects and awakenings were increased in 90%. Parental perception of sleep significantly differed from actigraphy results: parents estimated less sleep duration and less awakenings. Nocturnal sleep efficiency at baseline was reduced in 50%. After intensified treatment, median SCORAD decreased from 58.5 to 31.3 (p=0.005), with significant improvement in sleep loss and pruritus visual analogue scales. Despite improvement of SCORAD and parental perception of sleep loss and pruritus, objective sleep duration and efficiency measured by actigraphy did not vary significantly after intensified treatment. Change in SCORAD, sleep loss and pruritus scales did not correlate significantly with change in sleep duration, efficiency or other actigraphic sleep quality measurements. Conclusions: Children with moderate-severe AD have sleep quality abnormalities, with decreased sleep duration, low sleep efficiency and increased awakenings. Improvement in AD severity upon intensified AD treatment was associated with improved parental perception of sleep loss, but not of objective sleep quality assessed by actigraphy.

Considering how spatial thinking connects to Science, Technology, Engineering and Mathematics (STEM) outcomes, recent studies have evaluated how spatial interventions impact elementary students’ math learning. While promising, these interventions tend to overlook other factors affecting math learning; perceptions of math abilities, beliefs about math, and math anxiety can also impact math performance. Additionally, perceptions of spatial skill and spatial anxiety impact spatial performance. This study investigated how elementary teachers’ perceptions of spatial thinking connects with math perceptions. Specifically, we focused on teachers’ attitudes and beliefs around three topics: teaching and learning math, spatial abilities, and spatial thinking in mathematics. We found that lower spatial anxiety related to lower anxiety about teaching math, greater alignment between math beliefs and math standards, and greater efficacy in teaching and learning math. Further, a factor analysis showed one factor that connected stereotypical math thinking with both math and spatial anxiety, and another that connected spatial competencies, teaching and learning math, and spatial thinking within math. To further evaluate spatial thinking in math, we introduced a math categorization and verified it using teachers’ ratings of teaching difficulty, visualization helpfulness, and spatial-thinking involvement. Structural equation models revealed that the level of spatial-thinking categorization was the best model of all three of the teachers’ ratings. Overall, results showed numerous connections between teachers’ attitudes and beliefs about mathematics and spatial thinking. Future intervention studies should consider teachers who are spatial and/or math-anxious, and future research should investigate the role of stereotypical thinking in spatial and math anxiety.

Children’s capacity to understand other people’s false beliefs is commonly tested in tasks in which children must predict the behavior of a person who has wrong information about an event. The results of new, non-verbal false belief tasks have led several researchers to conclude that false belief attribution appears during the second year of life. However, the available evidence is still inconclusive. In the present article, we show the findings of the first meta-analysis of all non-verbal false belief tasks. Results indicate that 2-year-old children might attribute false beliefs, but they also reveal a high heterogeneity in the effects and possible publication biases.