Knowledge that Transforms

Why do children’s memories often differ from adults’ after the same experience? Whereas prior work has focused on children’s immature memory mechanisms to answer this question, here we focus on the costs of attentional lapses for learning. We track sustained attention and memory formation across time in 7- to 10-year-old children and adults ( n = 120) to show that sustained attention causally shapes the fate of children’s individual memories. Moreover, children’s attention lapsed twice as frequently as adults’, and attention fluctuated with memory formation more closely in children than adults. In addition, although attentional lapses impaired memory for expected events in both children and adults, they impaired memory for unexpected events in children only. Our work reveals that sustained attention is an important cognitive factor that controls access to children’s long-term memory stores. Our work also raises the possibility that developmental differences in cognitive performance stem from developmental shifts in the ability to sustain attention.

Prominent theories of visual working memory postulate that the capacity to maintain a particular visual feature is fixed. In contrast to these theories, recent studies have demonstrated that meaningful objects are better remembered than simple, nonmeaningful stimuli. Here, we tested whether this is solely because meaningful stimuli can recruit additional features-and thus more storage capacity-or whether simple visual features that are not themselves meaningful can also benefit from being part of a meaningful object. Across five experiments (30 young adults each), we demonstrated that visual working memory capacity for color is greater when colors are part of recognizable real-world objects compared with unrecognizable objects. Our results indicate that meaningful stimuli provide a potent scaffold to help maintain simple visual feature information, possibly because they effectively increase the objects' distinctiveness from each other and reduce interference.

Much of human learning happens through interaction with other people, but little is known about how this process is reflected in the brains of students and teachers. Here, we concurrently recorded electroencephalography (EEG) data from nine groups, each of which contained four students and a teacher. All participants were young adults from the northeast United States. Alpha-band (8-12 Hz) brain-to-brain synchrony between students predicted both immediate and delayed posttest performance. Further, brain-to-brain synchrony was higher in specific lecture segments associated with questions that students answered correctly. Brain-to-brain synchrony between students and teachers predicted learning outcomes at an approximately 300-ms lag in the students' brain activity relative to the teacher's brain activity, which is consistent with the time course of spoken-language comprehension. These findings provide key new evidence for the importance of collecting brain data simultaneously from groups of learners in ecologically valid settings.

U.S. police departments have attempted to address racial inequities in policing with diversity training. However, little research has evaluated whether these trainings are effective at changing officers’ beliefs, motivations, and actions. To examine their efficacy, we tested a day-long implicit-bias-oriented diversity training designed to increase U.S. police officers’ knowledge of biases, concerns about bias, and use of evidence-based strategies to mitigate bias (total N = 3,764). The training was immediately effective at increasing knowledge about bias, concerns about bias, and intentions to address bias, relative to baseline. However, the effects were fleeting. Although the training was linked to higher knowledge for at least 1 month, it was ineffective at durably increasing concerns or strategy use. These findings suggest that diversity trainings as they are currently practiced are unlikely to change police behavior. We conclude with theorizing about what organizations and training programs could do for greater impact.

Neural processing of objects with action associations recruits dorsal visual regions more than the neural processing of objects without such associations. We hypothesized that because the dorsal and ventral visual pathways have differing proportions of magno- and parvocellular input, there should be behavioral differences in perceptual tasks between manipulable and nonmanipulable objects. This hypothesis was tested in college-age adults across five experiments ( Ns = 26, 26, 30, 25, and 25) using a gap-detection task, suited to the spatial resolution of parvocellular processing, and an object-flicker-discrimination task, suited to the temporal resolution of magnocellular processing. Directly predicted from the cellular composition of each pathway, a strong nonmanipulable-object advantage was observed in gap detection, and a small manipulable-object advantage was observed in flicker discrimination. Additionally, these effects were modulated by reducing object recognition through inversion and by suppressing magnocellular processing using red light. These results establish perceptual differences between objects dependent on semantic knowledge.

This Further Reflections piece was invited by the Editors of the journal to provide additional consideration of some of the significant issues under study in “The Relational Wear and Tear of Everyday Racism Among African American Couples” (Ong et al., 2022) available online at https://doi.org/10.1177/09567976221077041 and on pages XXX–XXX of this issue. Further Reflections are not commentaries on a particular article, though they are inspired by one. Rather, they provide broader perspectives on issues considered in Research Articles, beyond those that authors are able to provide in the Introduction and Discussion sections of their articles. The Editors’ objective with Further Reflections is that they will raise the level of conversation around psychological issues of societal importance. Further Reflections are by invitation only.

Bastian et al. (2014) found that sharing a painful experience promoted later intergroup cooperation. In Bastian et al.’s second experiment, 62 participants were assigned to groups of two to six people each. They performed either two painful or two painless tasks and then played an economic game. The present study consisted of two replications of the experiment: The first was a nonpreregistered pilot study ( N = 153 students from the Czech Republic), and the second was a preregistered direct replication ( N = 158 students from Slovakia). Important deviations from the original procedure were that (a) gender homogeneity of the small groups was balanced across the conditions and (b) the number of participants in each small group was fixed at three. No relevant effect of shared pain on cooperation emerged. The findings indicate that the true effect of shared pain on cooperation obtained in the original study may have been an overestimate or that the effect is not generally valid across various contexts.

Repeatedly exercising a perceptual ability usually leads to improvement, yet it is unclear whether the mechanisms supporting the same perceptual learning could be flexibly adjusted according to the training settings. Here, we trained adult observers in an orientation-discrimination task at either a single (focused) retinal location or multiple (distributed) retinal locations. We examined the observers’ discriminability ( N = 52) and bias ( N = 20) in orientation perception at the trained and untrained locations. The focused and distributed training enhanced orientation discriminability by the same amount and induced a bias in perceived orientation at the trained locations. Nevertheless, the distributed training promoted location generalization of both practice effects, whereas the focused training resulted in specificity. The two training tactics also differed in long-term retention of the training effects. Our results suggest that, depending on the training settings of the same task, the same discrimination learning could differentially engage location-specific and location-invariant representations of the learned stimulus feature.

Theories of how people value and search for information share the assumption that beliefs give rise to the perceived value of information. However, few studies have directly addressed the pre-search processes that influence information-foraging behavior. This experiment examined the influence of pre-search belief updating on the perceived value of information sources. A sample of college students completed a hypothesis-testing, medical-diagnosis task. The experiment used medical tests with equal objective informative value before unveiling a presenting symptom intended to alter the strength of belief in different disease hypotheses. The observed patterns of test selection suggest that changes in beliefs about disease hypotheses result in systematic and predictable changes in test preference—a notion we refer to as the principle of hypothesis-guided search . We also present a simulation of how pre-search processes (e.g., hypothesis generation and working memory capacity) and task variables (e.g., time pressure) influence subsequent information search.

Orientation sensitivity is a fundamental property of the visual system, but not all orientations are created equal. For instance, radially oriented stimuli, aligned with a line intersecting the center of gaze, produce greater activity throughout the visual cortex and are associated with greater perceptual sensitivity compared with other orientations. Here, we discuss a robust visual illusion that is likely related to this preference. Using a continuous response measure, participants ( N = 36 adults) indicated the gap position in a peripheral Landolt C placed in one of eight orientations and eight locations along four meridians (vertical, horizontal, 45°, 135°). The error distributions revealed that the perceived gap was attracted toward the radial axis. For instance, the gap in a regular C would often be wrongly perceived as tilted 45° corresponding to the oblique meridian where it was placed. These findings demonstrate an unsuspected early-vision influence on the perceived orientation of an object.