Test-potentiated learning of motor sequences

We investigated effects of retrieving body movements from memory on subsequent re-encoding of these movements (i.e., test-potentiated learning). In Experiment 1, participants first learned to perform 12 sequential finger movements as responses to letter stimuli. Eight of these movements then had to be recalled in response to their stimuli (initial test). Subsequently, learning trials were repeated for four of the previously to-be-retrieved movements as well as the previously not-to-be-retrieved movements. Restudy benefited from prior retrieval. In a final test, again requiring motoric recall in response to letter stimuli, performance was better for restudied items that were previously cued for retrieval as compared to items that had been restudied without prior retrieval. However, no such indirect testing benefit occurred when initial and final testing formats were incongruent, that is, when participants had to recall the stimuli in response to movements as cues at the final test. In Experiment 2, we replicated the finding of test-potentiated learning with a different design, manipulating initial-testing status between participants.     

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.     

Self-regulation and selective exposure: the impact of depleted self-regulation resources on confirmatory information processing

In the present research, the authors investigated the impact of self-regulation resources on confirmatory information processing, that is, the tendency of individuals to systematically prefer standpoint-consistent information to standpoint-inconsistent information in information evaluation and search. In 4 studies with political and economic decision-making scenarios, it was consistently found that individuals with depleted self-regulation resources exhibited a stronger tendency for confirmatory information processing than did individuals with nondepleted self-regulation resources. Alternative explanations based on processes of ego threat, cognitive load, and mood were ruled out. Mediational analyses suggested that individuals with depleted self-regulation resources experienced increased levels of commitment to their own standpoint, which resulted in increased confirmatory information processing. In sum, the impact of ego depletion on confirmatory information search seems to be more motivational than cognitive in nature.     

Multiple conflict-driven control mechanisms in the human brain

Conflict between competing neural representations is thought to serve as an internal signal for the recruitment of 'cognitive control', which resolves conflict by biasing information processing in line with current task demands. Because conflict can occur at different levels of stimulus and response representations, several recent investigations have examined whether conflict-driven cognitive control is domain-general or domain-specific, that is, whether control recruited by one type of conflict affects the resolution of another, but these studies have produced contrary conclusions. I argue here that a critical reading of this literature indicates that the effects of conflict-driven control are domain-specific and are probably mediated by multiple, independent conflict-control loops that can operate in parallel.     

Change of reference frame for tactile localization during child development

Temporal order judgements (TOJ) for two tactile stimuli, one presented to the left and one to the right hand, are less precise when the hands are crossed over the midline than when the hands are uncrossed. This ‘crossed hand’ effect has been considered as evidence for a remapping of tactile input into an external reference frame. Since late, but not early, blind individuals show such remapping, it has been hypothesized that the use of an external reference frame develops during childhood. Five‐ to 10‐year‐old children were therefore tested with the tactile TOJ task, both with uncrossed and crossed hands. Overall performance in the TOJ task improved with age. While children older than 5½ years displayed a crossed hand effect, younger children did not. Therefore the use of an external reference frame for tactile, and possibly multisensory, localization seems to be acquired at age 5.     

Acquiring experiential traces in word-referent learning

In two experiments, we investigated the activation of perceptual representations of referent objects during word processing. In both experiments, participants learned to associate pictures of novel three-dimensional objects with pseudowords. They subsequently performed a recognition task (Experiment 1) or a naming task (Experiment 2) on the object names while being primed with different types of visual stimuli. Only the stimuli that the participants had encountered as referent objects during the training phase facilitated recognition or naming responses. New stimuli did not facilitate the processing of object names, even if they matched a schematic or prototypical representation of the referent object that the participants might have abstracted during word-referent learning. These results suggest that words learned by way of examples of referent objects are associated with experiential traces of encounters with these objects.     

Why and when justice sensitivity leads to pro- and antisocial behavior

People differ in how injustice-sensitive they are either as victims or as observers. Whereas observer sensitivity is positively related to cooperative behavior, victim sensitivity promotes antisocial and egoistic behavior. The present article investigates the dynamics underlying these effects. Participants played an online-based public goods game and were informed about the number of people who violated a fairness rule in previous rounds of the game (no, some, or many violators). High victim-sensitive participants contributed less to the public good even in the “some violators” condition. High observer-sensitive participants contributed more to the public good even in the “many violators” condition. The findings correspond with the sensitivity to mean intentions model and cannot be explained by individual differences in general trust.     

Biased assimilation: the role of source position

Biased assimilation is the tendency to evaluate belief‐consistent information more positively than belief‐inconsistent information. Previous research has demonstrated that biased assimilation is due to an inconsistency between an argument and the recipient's position toward this argument. The present research revealed that an inconsistency between a source's position (independently of the argument) and the recipient's position is also responsible for biased assimilation. In two studies, participants evaluated arguments stated by a politician. Party affiliation of the politician was correctly labeled, incorrectly labeled, or not labeled. The politicians' arguments were evaluated more favorably by their respective voters when party affiliation was correctly labeled. This biased evaluation diminished when party affiliation was not labeled and even slightly reversed when party affiliation was incorrectly labeled. Copyright © 2008 John Wiley & Sons, Ltd.