The debate on the Ego-Depletion Effect: evidence from meta-analysis with the p-Uniform Method

This research was supported by grant PSI2013-45513-P (Ministerio de Economía y Competitividad, Spain

The time course of visual foraging in the lifespan: Spatial scanning, organization search, and target processing

Visual foraging is a variant of visual search, consisting of searching for an undetermined number of targets among distractors (e.g., looking for various LEGO pieces in a box). Under non-exhaustive tasks, the observer scans the display, picking those targets needed, not necessarily all of them, before leaving the search. To understand how the organization of such natural foraging tasks works, several measures of spatial scanning and organization have been proposed in the exhaustive foraging literature: best-r, intertarget distances, PAO, and target intersections. In the present study, we apply these measures and new Bayesian indexes to determine how the time course of visual foraging is organized in a dynamic non-exhaustive paradigm. In a large sample of observers (279 participants, 4–25 years old), we compare feature and conjunction foraging and explore how factors like set size and time course, not previously tested in exhaustive foraging, might afect search organization in non-exhaustive dynamic tasks. The results replicate previous fndings showing younger observers’ searching being less organized, feature conditions being more organized than conjunction conditions, and organization leading to a more efective search. Interestingly, observers tend to be less organized as set size increases, and search is less organized within a patch as it advances in time: Search organization decreases when search termination is coming, suggesting organization measures as potential clues to understand quitting rules in search. Our results highlight the importance of studying search organization in foraging as a critical source of understanding complex cognitive processes in visual searchOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was supported by the Research Grant Project PSI2015-69358-R (MINECO/FEDER) “Ministerio de Economía y Competitividad” (MINECO), and “Fondo Europeo de Desarrollo Regional” (FEDER), given to Beatriz Gil-Gómez de Liaño as PI at Universidad Autónoma de Madrid. Also, part of the research of this study was done thanks to the Fulbright Commission, and the European Union’s Horizon 2020 research and innovation program, Marie Sklodowska-Curie Actions, under Grant FORAGEKID 793268, also granted to Beatriz Gil-Gómez de Liaño at the University of Cambridge, Universidad Complutense de Madrid, and BWH-Harvard Medical Schoo

Foraging behavior in visual search: a review of theoretical and mathematical models in humans and animals

Visual search (VS) is a fundamental task in daily life widely studied for over half a century. A variant of the classic paradigm—searching one target among distractors—requires the observer to look for several (undetermined) instances of a target (so-called foraging) or several targets that may appear an undefined number of times (recently named as hybrid foraging). In these searches, besides looking for targets, the observer must decide how much time is needed to exploit the area, and when to quit the search to eventually explore new search options. In fact, visual foraging is a very common search task in the real world, probably involving additional cognitive functions than typical VS. It has been widely studied in natural animal environments, for which several mathematical models have been proposed, and just recently applied to humans: Lévy processes, composite and area-restricted search models, marginal value theorem, and Bayesian learning (among others). We conducted a systematic search in the literature to understand those mathematical models and study its applicability in human visual foraging. The review suggests that these models might be the first step, but they seem to be limited to fully comprehend foraging in visual search. There are essential variables involving human visual foraging still to be established and understood. Indeed, a jointly theoretical interpretation based on the different models reviewed could better account for its understanding. In addition, some other relevant variables, such as certain individual differences or time perception might be crucial to understanding visual foraging in humansThe present work has been supported by the financed research project of the “Ministerio de Economía y Competitividad de España, Dirección General de Investigación Científica y Técnica”. Ref. PSI2015-69358-

Methods for estimating the sampling variance of the standardized mean difference

One of the most widely used effect size indices for meta-analysis in psychology is the standardized mean difference (SMD). The most common way to synthesize a set of estimates of the SMD is to weight them by the inverse of their variances. For this, it is necessary to estimate the corresponding sampling variances. Meta-analysts have a formula for obtaining unbiased estimates of sampling variances, but they often use a variety of alternative, simpler methods. The bias and efficiency of five different methods that have been proposed and that are implemented in different computerized calculation tools are compared and assessed. The data from a set of published meta-analyses are also reanalyzed, calculating the combined estimates and their confidence intervals, as well as estimates of the specific, between-studies variance, using the five estimation methods. This test of sensitivity shows that the results of a meta-analysis can change noticeably depending on the method used to estimate the sampling variance of SMD values, especially under a random-effects model. Some practical recommendations are made about how to choose and implement the methods in calculation resourcesThis research was supported by a grant from the Ministerio de Economía, Industria y Competitividad of Spain, Project No. PSI2017-82490-P

En busca de una explicación del Efecto Secuencial de Compatibilidad

Se estudia la modulación del Efecto de Compatibilidad (EC) según la compatibilidad del ensayo previo (Efecto Secuencial de Compatibilidad, ESC) en tres tipos de tareas atencionales, flancos verbal, flancos numérico y Stroop espacial, modeladas a partir de Gratton et al., (1992). Las tareas de flancos y Stroop espacial presentan diferente complejidad cognitiva. Se analiza en estas tareas si la modulación del EC está matizada por la repetición de estímulos exactamente iguales consecutivos (puras réplicas) o es independiente de ésta. Se registran datos de tres muestras independientes (Ntotal = 1.159) para averiguar si los resultados logran reproducirse. Se observa EC para las tres tareas atencionales, pero sólo hay ESC en la tarea de Stroop espacial. El efecto se mantiene después de eliminar del análisis los ensayos que son puras réplicas, un resultado inconsistente con las propuestas de Mayr et al. (2003) y Hommel (1998) pero congruente con la Teoría del Conflicto (Botvinick et al., 2001). Además, se analiza la importancia de la complejidad cognitiva en relación a la perspectiva de Botvinick et al. (2004). Desde este punto de vista una mayor complejidad se debería reflejar en una mayor presencia de conflicto cognitivo, y, por tanto, un mayor ESC.The modulation of the Compatibility Effect (CE) according to the compatibility of the previous trial (Sequential Compatibility Effect, SCE) in three types of attentional tasks is explored. The flankers and spatial Stroop tasks have different degrees of cognitive complexity. In all three tasks it is analyzed whether the SCE varies when the stimuli in consecutive trials are exactly the same (pure replicas) or not. The data, collected from three independent samples (total N = 1.159), show the CE in the three tasks. However, SCE only shows up in the spatial Stroop task. The effect is smaller albeit still significant when the pure replica trials are removed, a result inconsistent with those of Mayr et al. (2003) and Hommel (1998) but consistent with the Conflict Theory (Botvinick et al., 2001). Furthermore, we also discuss the importance of cognitive complexity in relation to the perspective of Botvinick et al. (2004). From this point of view more complexity should be reflected in a greater presence of cognitive conflict, and therefore a higher SCE

Regression toward the mean associated with extreme groups and the evaluation of improvement

Regression toward the mean effect (tendency of extreme data to resemble their mean when measurements are repeated) threatened internal validity when, in a group of extreme subjects, we attempted to test whether pre/post difference in values is due to our intervention. We are still unaware how and how much it affects: a) as a function of selection value, and b) statistical testing. This study demonstrates detection, measurement and correction of the effect. Its objective was achieved through a simulation of extreme groups, measured before and after a null treatment. The effect was measured by comparing simulated with assumed sample distribution. Correction was made by calculating the value of the alpha of the testing of the null hypothesis needed to cancel out the effec

A Model of the Formation of Illusory Conjunctions in the Time Domain

The authors present a model to account for the miscombination of features when stimuli are presented using the rapid serial visual presentation (RSVP) technique (illusory conjunctions in the time domain). It explains the distributions of responses through a mixture of trial outcomes. In some trials, attention is successfully focused on the target, whereas in others, the responses are based on partial information. Two experiments are presented that manipulated the mean processing time of the target-defining dimension and of the to-be-reported dimension, respectively. As predicted, the average origin of the responses is delayed when lengthening the target-defining dimension, whereas it is earlier when lengthening the to-be-reported dimension; in the first case the number of correct responses is dramatically reduced, whereas in the second it does not change. The results, a review of other research, and simulations carried out with a formal version of the model are all in close accordance with the predictions.Sin financiación2.498 JCR (2001) Q1, 10/64 Psychology, ExperimentalUE