When the ordinary seems unexpected: evidence for incremental physical knowledge in young infants

According to a recent account of infants' acquisition of their physical knowledge, the incremental-knowledge account, infants form distinct event categories, such as occlusion, containment, support, and collision events. In each category, infants identify one or more vectors which correspond to distinct problems that must be solved. For each vector, infants acquire a sequence of variables that enables them to predict outcomes within the vector more and more accurately over time. This account predicts that infants who have acquired only a few of the variables in a sequence should err in two ways in violation-of-expectation tasks: (1) they should view impossible events consistent with their incomplete knowledge as expected (errors of omission), and (2) they should view possible events inconsistent with their incomplete knowledge as unexpected (errors of commission). Many reports have shown that infants who have not yet identified a variable in an event category produce errors of omission: they fail to view impossible events involving the variable as unexpected. However, there has been no report revealing errors of commission in infants' responses to possible events. The present research examined whether 3- and 2.5-month-old infants, whose knowledge of occlusion events is very limited, would produce errors of commission as well as errors of omission when responding to these events. At 3 months of age, infants viewed as unexpected a possible event in which a tall cylinder became visible when passing behind a tall screen with a very large opening extending from its upper edge. At 2.5 months, infants viewed as unexpected a possible event in which a tall cylinder became visible when passing behind a tall screen with a very large opening extending from its lower edge. These findings provide a new kind of evidence for the incremental-knowledge account, and more generally for the notion that infants, like older children and adults, engage in rule-based reasoning about physical events.     

The daily life of the garden-variety neurotic: reactivity, stressor exposure, mood spillover, and maladaptive coping

This article describes a series of studies using the daily process paradigm to describe and understand the affective dynamics of people who experience frequent and intense bouts of a wide range of negative emotions. In several studies, community residents reported on problem occurrence and affect several times a day or at the end of the day. We found reliable evidence that persons who scored high (vs. low) in Neuroticism reported more daily problems, tended to react with more severe emotions, experienced more mood spillover from prior occasions, and exhibited stronger reactions to recurring problems (the "neurotic cascade"). The susceptibility of neurotics to stress seems to extend to all types of problems while certain other dimensions of personality (e.g., Agreeableness) are associated with hyperreactivity to particular kinds of problems. The research demonstrates how daily process research can provide insight about classic problems in the field of individual differences.     

Optic-flow-based perception of two-dimensional trajectories and the effects of a single landmark

Human observers can detect their heading direction on a short time scale on the basis of optic flow. We investigated the visual perception and reconstruction of visually travelled two-dimensional (2-D) trajectories from optic flow, with and without a landmark. As in our previous study, seated, stationary subjects wore a head-mounted display in which optic-flow stimuli were shown that simulated various manoeuvres: linear or curvilinear 2-D trajectories over a horizontal plane, with observer orientation either fixed in space, fixed relative to the path, or changing relative to both. Afterwards, they reproduced the perceived manoeuvre with a model vehicle, whose position and orientation were recorded. Previous results had suggested that our stimuli can induce illusory percepts when translation and yaw are unyoked. We tested that hypothesis and investigated how perception of the travelled trajectory depends on the amount of yaw and the average path-relative orientation. Using a structured visual environment instead of only dots, or making available additional extra-retinal information, can improve perception of ambiguous optic-flow stimuli. We investigated the amount of necessary structuring, specifically the effect of additional visual and/or extra-retinal information provided by a single landmark in conditions where illusory percepts occur. While yaw was perceived correctly, the travelled path was less accurately perceived, but still adequately when the simulated orientation was fixed in space or relative to the trajectory. When the amount of yaw was not equal to the rotation of the path, or in the opposite direction, subjects still perceived orientation as fixed relative to the trajectory. This caused trajectory misperception because yaw was wrongly attributed to a rotation of the path: path perception is governed by the amount of yaw in the manoeuvre. Trajectory misperception also occurs when orientation is fixed relative to a curvilinear path, but not tangential to it. A single landmark could improve perception. Our results confirm and extend previous findings that, for unambiguous perception of ego-motion from optic flow, additional information is required in many cases, which can take the form of fairly minimal, visual information.     

Inducing infants to detect a physical violation in a single trial

There is increasing evidence that infants' representations of physical events can be enhanced through appropriate experiences in the laboratory. Most of this research has involved administering infants multiple training trials, often with multiple objects. In the present research, 8-month-olds were induced to detect a physical violation in a single trial. The experiments built on previous evidence that for occlusion events, infants encode height information at about age 3.5 months, but for covering events, they encode height information only at about age 12 months. In two experiments, a short cover was first placed in front of a short or a tall object (occlusion event); next, the cover was lowered over the tall object until it became fully hidden (covering event). Exposure to the occlusion event (but not other events in which height information was not encoded) enabled the infants to detect the violation in the covering event, much earlier than they would have otherwise.     

You can't always get what you want: effortful control and children's responses to undesirable gifts

This study examined individual differences in children's regulation of emotional expression after receiving desirable and undesirable gifts. Effortful control, the ability to suppress a dominant response in favor of a subdominant one, was measured using a battery of behavioral tasks. Reactions to the gifts were videotaped, and emotional expression was coded. Age predicted effortful control, but not emotional displays. Effortful control predicted similarity of children's displays of positive affect after receiving the two gifts. Specifically, children high in effortful control showed similar amounts of positive affect after receiving the desirable and undesirable gifts, whereas children low in effortful control showed less positive affect after receiving the undesirable gift than after receiving the desirable gift. Results are discussed in terms of temperament and the development of socially appropriate expressive behavior.     

Activating the critical lure during study is unnecessary for false recognition

Participants studied lists of nonwords (e.g., froost, floost, stoost, etc.) that were orthographic-phonologically similar to a nonpresented critical lure, which was also a nonword (e.g., ploost). Experiment 1 showed a high level of false recognition for the critical lure. Experiment 2 showed that the false recognition effect was also present for forewarned participants who were informed about the nature of the false recognition effect and told to avoid making false recognition judgments. The present results show that false recognition effects can be obtained even when the critical lure itself is not stored during study. This finding is problematic for accounts that attribute false memories to implicit associative responses or spreading activation but is easily explained by global familiarity models of recognition memory.     

Intergroup threat,knowledge of the outgroup,and willingness to purchase ingroup and outgroup products: The mediating role of intergroup emotions

Established theories have acknowledged that intergroup threat is one of the key determinants of intergroup attitudes and behaviours, but how intergroup threat can affect consumer behaviour remains unclear. Here, four preregistered studies (total N = 988) examined the effect of intergroup threat (manipulated in terms of realistic and symbolic threats) on consumers’ willingness to purchase ingroup and outgroup products. In the context of China–West relations, we measured Chinese consumers’ willingness to purchase Chinese (ingroup) and Western (outgroup) products. These studies together revealed that realistic and symbolic threats (versus control) increased willingness to purchase ingroup products and decreased willingness to purchase outgroup products, regardless of the product category. Studies 3a and 3b also measured knowledge of the outgroup as a potential moderator, revealing that realistic threat (versus control) reduced willingness to purchase outgroup products only among individuals who had less knowledge of the outgroup. Furthermore, Study 3b showed that the intergroup threat manipulation indirectly influenced consumers’ willingness to purchase ingroup/outgroup products through increased anger and decreased hope. We discussed the contributions to the intergroup relations and consumer behaviour literature and the implications for transnational marketing practices, as well as the limitations of this research.     

Ability to stand alone and processing of open-class and closed-class words: Isolation versus context

Four experiments investigating processing of closed-class and open-class words in isolation and in sentence contexts are reported. Taft (1990) reported that closed-class words which could not meaningfully stand alone and open-class words which could not meaningfully stand alone incurred longer lexical decision responses than did control words. Taft also reported that closed-class and open-class words which could stand alone meaningfully were not associated with longer lexical decision responses than were control words. Experiments 1 and 2 replicated Taft 's effect of ability to stand alone on lexical decision responses to closed-class and open-class words presented in isolation. In Experiments 3 and 4, the same lexical decision targets were presented as part of semantically neutral context sentences in a moving window paradigm. The stand-alone effect was not present in Experiments 3 and 4. The results suggest Toft's conclusion that meaningfulness of a word influences lexical decision needs revision. An explanation is provided according to which support from message level and syntactic and lexical sources in sentence contexts influence words' perceived “meaningfulness.”     

Case vignette: child abuse or acceptable cultural norms -- child psychiatrist's response; ethical issues in culturally relevant interventions; cultural contexts

Three families from the nation of the Gambia have become socially acquainted in the greater Metropolis area where they have relocated from their native country. All three families have preadolescent daughters. None of the girls has as yet undergone the ritual "female circumcision" commonly practiced in their native country. Five of the six parents think it would be a good idea to hold such a ritual ceremony in Metropolis next month. The sixth parent is uneasy about the procedure and wonders if it is appropriate anyway. The parent comes to talk with you, a physician or mental health professional, about this. The parent describes concerns about the procedure and the practice in general, but notes that some groups in the United States do "similar things," referring to the ritual circumcision of Jewish boys at 8 days of age. The parent adds that if the procedure is not possible in the United States, it could be done in the Gambia when the family returns there on holiday. Discussants were asked for their opinions regarding advice to the parent's ethical obligations (especially in the case of mandated reporting of suspected child abuse).