Adolescent anxiety and aggression can be differentially predicted by electrocortical phase reset variables

Increasing evidence supports the notion that both internalizing (e.g., anxiety) and externalizing (e.g., aggression) behavioral dysregulation are associated with abnormal communication between brain regions. Electroencephalographic (EEG) signals across two electrode sites are said to be coherent with one another when they show consistent phase relations. However, periods of desynchrony with shifting of phase relations are a necessary aspect of information processing. The components of EEG phase reset (‘locking’ when two regions remain in synchrony, and ‘shifting’ when the two regions desynchronize momentarily) show dramatic changes across development. We collected resting EEG data from typically developing 12 to 15-year-olds and calculated phase shift and lock values in the alpha frequency band across 14 pairs of electrodes varying in inter-electrode distance. A composite measure of participants’ aggression levels was positively associated with phase shifting, particularly in the low alpha frequency range, most strongly over the left hemisphere, consistent with the relatively greater left-prefrontal activity reported in aggressive adults. A composite measure of anxiety levels was positively associated with alpha phase locking at sites over both hemispheres, consistent with changes in connectivity reported during anxious thinking in adults. Associations with anxiety could not be explained by traditional EEG coherence measures and suggest that phase shifting and locking might provide an important non-invasive associate of clinically problematic behavior.     

Exemplar theory's predicted typicality gradient can be tested and disconfirmed

One of exemplar theory's central predictions concerns the shape of typicality gradients. The typicality gradient it predicts is a consequence of its exemplar–based comparisons and appears no matter how the theory is evaluated. However, this predicted typicality gradient does not fit the empirical typicality gradients obtained in an influential version of the dot–distortion category task, and this is true even when the exemplar model is made more flexible and mathematically powerful. Thus, exemplar theory is disconfirmed in this domain of categorization. In contrast, prototype theories are consistent with the empirically obtained typicality gradients.     

Extinction can be enhanced by a concurrent excitor

Five experiments used rat subjects to investigate the impact on extinction of the presence of other conditioned stimuli. In Experiments 1 (Pavlovian magazine approach) and 2 (instrumental discriminative training), an excitatory stimulus (X) was extinguished alone, in conjunction with a previously reinforced other stimulus (A), in conjunction with previously nonreinforced other stimulus (B), or it was spared extinction. Responding during extinction was greatest to AX, and subsequent testing of X alone showed AX extinction to have produced the most decrement to X. Experiment 3 found similar results using a within-subject design. Experiment 5 continued separate reinforced presentations of A during extinction. This procedure not only promoted extinction of X but also converted it into a conditioned inhibitor. These experiments bear on the mechanisms of overshadowing and stimulus processing, as well as provide information on the determinants of extinction.     

Seven‐year‐olds’ aggressive choices in a computer game can be predicted in infancy

Concerns about the relationship between computer games and children's aggression have been expressed for decades, but it is not yet clear whether the content of such games evokes aggression or a prior history of aggression promotes children's interest in aggressive games. Two hundred and sixty‐six 7‐year‐old children from a nationally representative longitudinal sample in the UK played a novel computer game (CAMGAME) in which the child's avatar encountered a series of social challenges that might evoke aggressive, prosocial or neutral behaviour. Aggressive choices during the game were predicted by well‐known risk factors for aggressive conduct problems and the children's own early angry aggressiveness as infants. These findings suggest that children who are predisposed to aggression bring those tendencies to virtual as well as real environments.     

Metacognitive illusions can be reduced by monitoring recollection during study

Prior work has shown that judgments of learning (JOLs) are prone to an auditory metacognitive illusion such that loud words are given higher predictions than quiet words despite no differences in recall as a function of auditory intensity. The current study investigated whether judgments of remembering and knowing (JORKs)—judgments that focus participants on whether or not recollective details will be remembered—are less susceptible to such an illusion. In Experiment 1, participants studied single words, making item-by-item JOLs or JORKs immediately after study. Indeed, although increased volume elevated judgement magnitude for both JOLs and JORKs, the effect was significantly attenuated when JORKs were elicited. Experiment 2 replicated this finding and additionally demonstrated that participants making JORKs were less likely than participants making JOLs to choose to restudy quiet words relative to loud words. Taken together, these results suggest that JORKs are impacted less—in terms of both metacognitive monitoring and control—by irrelevant perceptual information than JOLs. More generally, these data support the contention that metacognitive illusions can be attenuated by simply changing the way metacognitive judgments are solicited, an important finding given that subjective experiences guide self-regulated learning.     

Older readers can be distracted by embellishing graphics in text

In most research on graphics in text students learn the content for a test (e.g., Mayer, 2002). The present study examined whether one of the principles from that literature, namely the deleterious effect of extraneous graphic information, would apply to adults who were consulting a leaflet to answer questions. The study used a mixed factorial design with 48 participants from three age bands (young-adult, young-old, old-old). Participants used two leaflets to answer questions, one without graphics and the other with either extraneous embellishing or supportive explanatory graphics. Relative to leaflets without graphics, the old-old participants were significantly slower finding information when leaflets contained embellishing but not explanatory graphics. The graphics had no effect on the other age groups. These findings suggest that either the reading task or the thematic relevance of the extraneous graphics may limit their negative effects for most adults but that negative effects recur for older readers.     

Visual apparent motion can be modulated by task-irrelevant lexical information

Previous studies have repeatedly demonstrated the impact of Gestalt structural grouping principles upon the parsing of motion correspondence in ambiguous apparent motion. Here, by embedding Chinese characters in a visual Ternus display that comprised two stimulus frames, we showed that the perception of visual apparent motion can be modulated by activation of task-irrelevant lexical representations. Each frame had two disks, with the second disk of the first frame and the first disk of the second frame being presented at the same location. Observers could perceive either "element motion," in which the endmost disk is seen as moving back and forth while the middle disk at the central position remains stationary, or "group motion," in which both disks appear to move laterally as a whole. More reports of group motion, as opposed to element motion, were obtained when the embedded characters formed two-character compound words than when they formed nonwords, although this lexicality effect appeared to be attenuated by the use of the same characters at the overlapping position across the two frames. Thus, grouping of visual elements in a changing world can be guided by both structural principles and prior world knowledge, including lexical information.     

数量信息不能引发符号的空间表征

该研究为了考察数量信息能否独立引发符号的空间表征,采用若干面积不等的圆和点数不同的点阵作为实验刺激,让被试用左右手按键,判断圆面积的大小,以及点阵点数的多少。结果发现,无论在面积大小判断任务中,还是在点数数量判断任务中,都没有产生SNARC效应。这说明,单纯的数量信息,并不能引发符号进行空间表征。这一结果也在一定程度上支持了Gevers等人的假设:数字的空间表征,是由数字的顺序性信息决定的,而并非是由其数量信息决定的。     

The influence of the human TMJ eminence inclination on predicted masticatory muscle forces

Aim of this paper was to investigate the change in masticatory muscle forces and temporomandibular joint (TMJ) reaction forces simulated by inverse dynamics when the steepness of the anterior fossa slope was varied. We used the model by de Zee et al. (2007) created in AnyBody™. The model was equipped with 24 musculotendon actuators. Mandibular movement was governed by the trajectory of the incisal point. The TMJ was modelled as a planar constraint canted 5° medially and the caudal inclination relative to the occlusal plane was varied from 10° to 70°. Our models showed that for the two simulated movements (empty chewing and unilateral clenching) the joint reaction forces were smallest for the eminence inclination of 30° and 40° and highest for 70°. The muscle forces were relatively insensitive to change of the eminence inclination for the angles between 20° and 50°. This did not hold for the pterygoid muscle, for which the muscle forces increased continually with increasing fossa inclination. For empty chewing the muscle force reached smaller values than for clenching. During clenching, the muscle forces changed by up to 200 N.     

Visual search for object orientation can be modulated by canonical orientation

The authors studied the influence of canonical orientation on visual search for object orientation. Displays consisted of pictures of animals whose axis of elongation was either vertical or tilted in their canonical orientation. Target orientation could be either congruent or incongruent with the object's canonical orientation. In Experiment 1, vertical canonical targets were detected faster when they were tilted (incongruent) than when they were vertical (congruent). This search asymmetry was reversed for tilted canonical targets. The effect of canonical orientation was partially preserved when objects were high-pass filtered, but it was eliminated when they were low-pass filtered, rendering them as unfamiliar shapes (Experiment 2). The effect of canonical orientation was also eliminated by inverting the objects (Experiment 3) and in a patient with visual agnosia (Experiment 4). These results indicate that orientation search with familiar objects can be modulated by canonical orientation, and they indicate a top-down influence on orientation processing.     

The pursuit of happiness can be lonely

Few things seem more natural and functional than wanting to be happy. We suggest that, counter to this intuition, valuing happiness may have some surprising negative consequences. Specifically, because striving for personal gains can damage connections with others and because happiness is usually defined in terms of personal positive feelings (a personal gain) in western contexts, striving for happiness might damage people's connections with others and make them lonely. In 2 studies, we provide support for this hypothesis. Study 1 suggests that the more people value happiness, the lonelier they feel on a daily basis (assessed over 2 weeks with diaries). Study 2 provides an experimental manipulation of valuing happiness and demonstrates that inducing people to value happiness leads to relatively greater loneliness, as measured by self-reports and a hormonal index (progesterone). In each study, key potential confounds, such as positive and negative affect, were ruled out. These findings suggest that wanting to be happy can make people lonely. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Amplitude of constant-current pulses can be preset

The required magnitude of stimulation current can be adjusted with a voltage divider, consisting of a 10-turn potentiometer and a digital dial. This method of adjustment offers greater convenience than depending solely on a monitoring oscilloscope for current readings, especially when frequent changes in stimulation current must be made. Tissue polarization is prevented by a shunt gate, which is in operation during the pulse interval.     

Action goal selection and motor planning can be dissociated by tool use

The preparation of eye or hand movements enhances visual perception at the upcoming movement end position. The spatial location of this influence of action on perception could be determined either by goal selection or by motor planning. We employed a tool use task to dissociate these two alternatives. The instructed goal location was a visual target to which participants pointed with the tip of a triangular hand-held tool. The motor endpoint was defined by the final fingertip position necessary to bring the tool tip onto the goal. We tested perceptual performance at both locations (tool tip endpoint, motor endpoint) with a visual discrimination task. Discrimination performance was enhanced in parallel at both spatial locations, but not at nearby and intermediate locations, suggesting that both action goal selection and motor planning contribute to visual perception. In addition, our results challenge the widely held view that tools extend the body schema and suggest instead that tool use enhances perception at those precise locations which are most relevant during tool action: the body part used to manipulate the tool, and the active tool tip.     

Set-specific capture can be reduced by preemptively occupying a limited-capacity focus of attention

Recent work has shown that contingent attentional capture effects can be especially large when multiple attentional sets for color guide visual search (Moore & Weissman, 2010). In particular, this research suggests that detecting a target-colored (e.g., orange) distractor leads the corresponding attentional set (e.g., identify orange letters) to enter a limited-capacity focus of attention in working memory, where it remains briefly while the distractor is being attended. Consequently, the ability to identify a differently-colored (e.g., green) target 100-300 ms later is impaired because the appropriate set (e.g., identify green letters) cannot also enter the focus of attention. In two experiments, we investigated whether such set-specific capture can be reduced by preemptively occupying the focus of attention. As predicted, a target-colored central distractor presented 233 ms before a target-colored peripheral distractor eliminated set-specific capture arising from the peripheral distractor. Moreover, this effect was observed only when the central distractor's color (e.g., orange) (a) matched a different set than the upcoming peripheral distractor's color (e.g., green) and (b) matched the same set as the upcoming central target's color (e.g., orange). We conclude that the same working memory limitations that give rise to set-specific capture can be preemptively exploited to reduce it.     

Retrieval of event files can be conceptually mediated

Distractor-based retrieval of event files was assessed with a sequential priming experiment using a four-choice identification task. Pictures or sounds of four different animals (frog, chicken, lamb, singing bird) had to be categorized by pressing one of four keys. On each trial, a target and a distractor stimulus were presented simultaneously in different modalities. The relevant modality switched randomly between trials. Distractor repetition effects were modulated by the response relation between the prime and probe: Repeating the prime distractor in the probe produced facilitation if the response repeated, but not if a different response had to be given in the prime and probe. Repeating the prime distractor in the probe led to an automatic retrieval of the prime response. Importantly, this distractor-based response retrieval effect also emerged for those sequences in which the modality of the repeated distractor was switched between the prime and probe. This cross-modal priming effect indicates that distractors were integrated into event files on a conceptual level and that response retrieval processes were mediated by conceptual codes of the distractor stimuli.     

Race and gender of faces can be ignored

Past research indicates that faces can be more difficult to ignore than other types of stimuli. Given the important social and biological relevance of race and gender, the present study examined whether the processing of these facial characteristics is mandatory. Both unfamiliar and famous faces were assessed. Participants made speeded judgments about either the race (Experiment 1) or gender (Experiments 2–4) of a target name under varying levels of perceptual load, while ignoring a flanking distractor face that was either congruent or incongruent with the race/gender of the target name. In general, distractor–target congruency effects emerged when the perceptual load of the relevant task was low but not when the load was high, regardless of whether the distractor face was unfamiliar or famous. These findings suggest that face processing is not necessarily mandatory, and some aspects of faces can be ignored.