Mechanical invariants are implicated in dynamic touch as a function of their salience in the stimulus flow

The authors investigated the mechanical basis of length perception through dynamic touch using specially designed rods in which the various moments of mass distribution (mass, static moment, and rotational inertia) were varied independently. In a series of 4 experiments, exploration style and rod orientation were manipulated such that the relative salience of moments of mass distribution varied markedly. Results showed that perceived length was based on the most salient moments. The authors concluded that the notion of salience is crucial for understanding the implication of moments of mass distribution in length perception and that it should play a pivotal role in developing an encompassing theory of dynamic touch.     

Motor limitation in dual-task processing under ballistic movement conditions

The standard bottleneck model of the psychological refractory period (PRP) assumes that the selection of the second response is postponed until the first response has been selected. Accordingly, dual-task interference is attributed to a single central-processing bottleneck involving decision and response selection, but not the execution of the response itself. In order to critically examine the assumption that response execution is not part of this bottleneck, we systematically manipulated the temporal demand for executing the first response in a classical PRP paradigm. Contrary to the assumption of the standard bottleneck model, this manipulation affected the reaction time for Task 2. Specifically, reaction time for Task 2 increased with execution time for Task 1. This carryover effect from Task 1 to Task 2 provides evidence for the notion that response execution can be part of the processing bottleneck.     

Psychosocial stress enhances time-based prospective memory in healthy young men

Forgetting of intentions (such as to take one's medication) is the most frequent everyday memory failure. No study so far has looked into the possible consequences stress might exert on memory for intentions (i.e., prospective memory). Twenty healthy young male adults were exposed to a psychosocial stress test and a non-stress condition. After a delay of 15 min, a time- and an event-based prospective memory task were administered during the peak of cortisol concentrations. Results show that participants performed significantly better in the time-based memory task after stress in comparison to the non-stress condition. In contrast, there was no stress effect on event-based prospective memory. The results demonstrate that prospective memory might be enhanced when participants are exposed to stress prior to the memory task and that this effect is associated to stress-related glucocorticoid effects.     

Adolescent outcomes of childhood conduct disorder among clinic-referred boys: predictors of improvement

Much remains to be learned about the adolescent outcomes of clinic-referred boys whose childhood conduct problems are serious enough to meet diagnostic criteria for conduct disorder (CD). Six structured diagnostic assessments were conducted over 7 years of 73 clinic-referred 7–12-year-old boys who met criteria for CD in Wave 1. There were substantial individual differences in the adolescent outcomes of CD, ranging from worsening to sustained recovery, with most boys showing persistent, but fluctuating levels of CD. Improvement in CD was not accounted for by treatment or incarceration, but more positive outcomes over Waves 2–7 were predicted prospectively with substantial accuracy, using a combination of baseline predictors: less initial severity of CD, fewer symptoms of attention-deficit hyperactivity disorder, higher child verbal intelligence, greater family socioeconomic advantage, and not having antisocial biological parents.     

Aiming at a far target under different viewing conditions: visual control in basketball jump shooting

Most research on visual search in aiming at far targets assumes preprogrammed motor control implying that relevant visual information is detected prior to the final shooting or throwing movements. Eye movement data indirectly support this claim for stationary tasks. Using the basketball jump shot as experimental task we investigated whether in dynamic tasks in which the target can be seen until ball release, continuous, instead of preprogrammed, motor control is possible. We tested this with the temporal occlusion paradigm: 10 expert shooters took shots under four viewing conditions, namely, no vision, full vision, early vision (vision occluded during the final +/-350 ms before ball release), and late vision (vision occluded until these final +/-350 ms). Late-vision shooting appeared to be as good as shooting with full vision while early-vision performance was severely impaired. The results imply that the final shooting movements were controlled by continuous detection and use of visual information until ball release. The data further suggest that visual and movement control of aiming at a far target develop in close correspondence with the style of execution.     

Mechanisms underlying spatial coding in a multiple-item Simon task

Choice responses are faster when target position and response side correspond than when they do not, even if target position is response-irrelevant. This "Simon effect" has also been observed in case of multi-item arrays. Generally, it is assumed that an automatically generated spatial response code is responsible for the effect. The referential-coding account assumes that this code is directly related to the target, although the moment of production of the code is not fully clear. The attention-shift account assumes that the code is directly related to the direction of the most recent attentional shift. An experiment was performed in which left or right target locations were indicated by arrows occurring before (precue), simultaneous with (simcue), or after (postcue) six-element arrays. Overt responses and EEG potentials were recorded. The Simon effect was present in all conditions, and decreased when responses were slower. No relation was found between amplitude of posterior lateralized components and the magnitude of the Simon effect. A posterior contralateral negativity was also found after presenting the arrays in the precue condition, which might reflect the reorienting of attention toward the target position. The results are more favorable to the referential-coding account although this account becomes very similar to the attention-shift hypothesis as the moment of formation of the spatial response code is related to effective target onset rather than to stimulus onset.     

Perception of motion affects language processing

Recently developed accounts of language comprehension propose that sentences are understood by constructing a perceptual simulation of the events being described. These simulations involve the re-activation of patterns of brain activation that were formed during the comprehender's interaction with the world. In two experiments we explored the specificity of the processing mechanisms required to construct simulations during language comprehension. Participants listened to (and made judgments on) sentences that described motion in a particular direction (e.g. "The car approached you"). They simultaneously viewed dynamic black-and-white stimuli that produced the perception of movement in the same direction as the action specified in the sentence (i.e. towards you) or in the opposite direction as the action specified in the sentence (i.e. away from you). Responses were faster to sentences presented concurrently with a visual stimulus depicting motion in the opposite direction as the action described in the sentence. This suggests that the processing mechanisms recruited to construct simulations during language comprehension are also used during visual perception, and that these mechanisms can be quite specific.     

Spatial iconicity affects semantic relatedness judgments

Three experiments were conducted to examine whether spatial iconicity affects semantic-relatedness judgments. Subjects made speeded decisions with regard to whether members of a simultaneously presented word pair were semantically related. In Experiment 1, the words were presented one above the other. In the experimental pair, the words denoted parts of larger objects (e.g., ATTIC-BASEMENT). The words were either in an iconic relation with their referents (e.g., ATTIC presented above BASEMENT) or in a reverse-iconic relation (BASEMENT above ATTIC). The reverse-iconic condition yielded significantly slower semantic-relatedness judgments than did the iconic condition. Experiments 2 and 3 showed that this effect did not occur when the words were presented horizontally, thus ruling out that the iconicity effect is due to the order in which the words are read. Two alternative explanations for this finding are discussed.     

Reading problems and depressed mood

Although reading difficulties show well-established overlaps with disruptive behavior disorders in childhood, much less is known about reading-disabled children's vulnerability to emotional difficulties. Using longitudinal data from 6 assessments of boys in the Pittsburgh Youth Study, we found robust links between severe, persistent reading problems and increased risk for depressed mood in a community sample of boys aged 7 and 10 years at initial assessment, though not in those who had already entered their teens. These associations could not be accounted for in terms of selected family risks or comorbid disruptive behaviors; instead, the pattern of the findings pointed to the existence of more direct causal processes whereby reading problems influence younger boys' risk of depressed mood.     

Effects of negation and situational presence on the accessibility of text information

In 2 experiments, participants read narratives containing a color term that was mentioned either within the scope of an explicit negative or not, and with the described situation being such that the color was either present or not. Accessibility of the color term was measured by means of a probe-recognition task either 500 ms (Experiment 1) or 1,500 ms (Experiment 2) after participants read the sentence mentioning color. After the 500-ms delay, the accessibility of the color term was influenced by the structure of the sentence. After the 1,500-ms delay, the accessibility was influenced by the content of the described situation. These results are consistent with the view that comprehenders construct a linguistic representation of the text as well as a situation model in which only present properties are represented. An alternative account, according to which comprehenders only construct a perceptual simulation of the described situation, is discussed.