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In the research reported here, we found evidence of the cheerleader effect—people seem more attractive in a group than in isolation. We propose that this effect arises via an interplay of three cognitive phenomena: (a) The visual system automatically computes ensemble representations of faces presented in a group, (b) individual members of the group are biased toward this ensemble average, and (c) average faces are attractive. Taken together, these phenomena suggest that individual faces will seem more attractive when presented in a group because they will appear more similar to the average group face, which is more attractive than group members’ individual faces. We tested this hypothesis in five experiments in which subjects rated the attractiveness of faces presented either alone or in a group with the same gender. Our results were consistent with the cheerleader effect. [ABSTRACT FROM PUBLISHER]

Real-world visual searches often contain a variable and unknown number of targets. Such searches present difficult metacognitive challenges, as searchers must decide when to stop looking for additional targets, which results in high miss rates in multiple-target searches. In the study reported here, we quantified human strategies in multiple-target search via an ecological optimal foraging model and investigated whether searchers adapt their strategies to complex target-distribution statistics. Separate groups of individuals searched displays with the number of targets per trial sampled from different geometric distributions but with the same overall target prevalence. As predicted by optimal foraging theory, results showed that individuals searched longer when they expected more targets to be present and adjusted their expectations on-line during each search by taking into account the higher-order, across-trial target distributions. However, compared with modeled ideal observers, participants systematically responded as if the target distribution were more uniform than it was, which suggests that training could improve multiple-target search performance. [ABSTRACT FROM AUTHOR]

Probabilistic models of cognition characterize the abstract computational problems underlying inductive inferences and identify their ideal solutions. This approach differs from traditional methods of investigating human cognition, which focus on identifying the cognitive or neural processes that underlie behavior and therefore concern alternative levels of analysis. To evaluate the theoretical implications of probabilistic models and increase their predictive power, we must understand the relationships between theories at these different levels of analysis. One strategy for bridging levels of analysis is to explore cognitive processes that have a direct link to probabilistic inference. Recent research employing this strategy has focused on the possibility that the Monte Carlo principle—which concerns sampling from probability distributions in order to perform computations—provides a way to link probabilistic models of cognition to more concrete cognitive and neural processes. [ABSTRACT FROM PUBLISHER]

Over the past year, a heated discussion about ‘circular’ or ‘nonindependent’ analysis in brain imaging has emerged in the literature. An analysis is circular (or nonindependent) if it is based on data that were selected for showing the effect of interest or a related effect. The authors of this paper are researchers who have contributed to the discussion and span a range of viewpoints. To clarify points of agreement and disagreement in the community, we collaboratively assembled a series of questions on circularity herein, to which we provide our individual current answers in ≤100 words per question. Although divergent views remain on some of the questions, there is also a substantial convergence of opinion, which we have summarized in a consensus box. The box provides the best current answers that the five authors could agree upon. [ABSTRACT FROM AUTHOR]

Decades of research suggest that selective attention is critical for binding the features of objects together for conscious perception. A fundamental question, however, remains unresolved: How do people perceive objects, albeit with binding errors (illusory conjunctions ), when attentional resolution is poor? We used a novel technique to investigate how features are selected to create percepts of bound objects. We measured the correlation of errors (intrusions) in color and identity reports in spatial and temporal selection tasks under conditions of varying spatial or temporal uncertainty. Our findings suggest that attention selects each feature independently by randomly sampling from a probability distribution over space or time. Thus, veridical perception of bound object features arises only when attentional selection is sufficiently precise that the independently sampled features originate from a single object. [ABSTRACT FROM PUBLISHER]

The article presents the author's comments on an article about correlation between brain activity and behavioral measures of personality, emotion, and social cognition. He says that the magnitude of inflation varies from study to study, leaving no possibility to correct or estimate the inflation of any given result. He suggests to use independent methods to compute unbiased correlation coefficients, as it allows for simpler and more transparent inferential tests.

Functional magnetic resonance imaging (fMRI) studies of emotion, personality, and social cognition have drawn much attention in recent years, with high-profile studies frequently reporting extremely high (e.g., >.8) correlations between brain activation and personality measures. We show that these correlations are higher than should be expected given the (evidently limited) reliability of both fMRI and personality measures. The high correlations are all the more puzzling because method sections rarely contain much detail about how the correlations were obtained. We surveyed authors of 55 articles that reported findings of this kind to determine a few details on how these correlations were computed. More than half acknowledged using a strategy that computes separate correlations for individual voxels and reports means of only those voxels exceeding chosen thresholds. We show how this nonindependent analysis inflates correlations while yielding reassuring-looking scattergrams. This analysis technique was used to obtain the vast majority of the implausibly high correlations in our survey sample. In addition, we argue that, in some cases, other analysis problems likely created entirely spurious correlations. We outline how the data from these studies could be reanalyzed with unbiased methods to provide accurate estimates of the correlations in question and urge authors to perform such reanalyses. The underlying problems described here appear to be common in fMRI research of many kinds—not just in studies of emotion, personality, and social cognition. [ABSTRACT FROM AUTHOR]

To achieve enduring retention, people must usually study information on multiple occasions. How does the timing of study events affect retention? Prior research has examined this issue only in a spotty fashion, usually with very short time intervals. In a study aimed at characterizing spacing effects over significant durations, more than 1,350 individuals were taught a set of facts and—after a gap of up to 3.5 months—given a review. A final test was administered at a further delay of up to 1 year. At any given test delay, an increase in the interstudy gap at first increased, and then gradually reduced, final test performance. The optimal gap increased as test delay increased. However, when measured as a proportion of test delay, the optimal gap declined from about 20 to 40% of a 1-week test delay to about 5 to 10% of a 1-year test delay. The interaction of gap and test delay implies that many educational practices are highly inefficient. [ABSTRACT FROM AUTHOR]

How does temporal selection work, and along what dimensions does it vary from one instance to the next? We explored these questions using a phenomenon in which temporal selection goes awry. In the attentional blink, subjects fail to report the second of a pair of targets (T1 and T2) when they are presented at stimulus onset asynchronies (SOAs) of roughly 200 to 500 ms. We directly tested the properties of temporal selection during the blink by analyzing distractor intrusions at a fast rate of item presentation. Our analysis shows that attentional selection is (a) suppressed, (b) delayed, and (c) diffused in time during the attentional blink. These effects are dissociated by their time course: The measure of each effect returns to the baseline value at a different SOA. Our results constrain theories of the attentional blink and indicate that temporal selection varies along at least three dissociable dimensions: efficacy, latency, and precision. [ABSTRACT FROM AUTHOR]

The article discusses a study on the probabilistic representations in an individual's estimation responses. The study involved recruiting 428 participants from an Internet-based subject pool, and asking them questions that will probe their real-world knowledge. Some respondents were asked to make a second guess for each question immediately after completing the questionnaire, others were asked for second guesses after three weeks. Analysis of the data revealed that the average of the two guesses from each person was more accurate than either guess alone.