Timing the moment of impact in fast human movements

The reported resolution of timing the moment of impact in fast human movements differs widely depending on the task. Surprisingly, better timing is reported for the demanding task of batting a ball than for the much simpler task of tapping in synchrony with two hands. We wondered whether this is because a sizeable part of timing variability arises from misjudging the distance in the direction of one's own movement, so that moving faster (as the bat does when moving toward a ball) improves timing. We found that moving faster does indeed improve timing in both the above-mentioned tasks. After removing the proposed contribution of misjudging the distance in the direction of one's own movement, we estimated that the remaining standard deviation in timing is just over 6ms for both tasks.     

Temperature dependency in motor skill learning

The present study investigated the role of temperature as a contextual condition for motor skill learning. Precision grip task training occurred while forearm cutaneous temperature was either heated (40-45 °C) or cooled (10-15 °C). At test, temperature was either reinstated or changed. Performance was comparable between training conditions while at test, temperature changes decreased accuracy, especially after hot training conditions. After cold training, temperature change deficits were only evident when concurrent force feedback was presented. These findings are the first evidence of localized temperature dependency in motor skill learning in humans. Results are not entirely accounted for by a context-dependent memory explanation and appear to represent an interaction of neuromuscular and sensory processes with the temperature present during training and test.     

Daily fluctuations in perfectionism dimensions and their relation to eating disorder symptoms

Multidimensional perfectionism has been shown to play an important role in eating disorders (EDs). However, research examining this relation has primarily focused on relatively stable inter-individual differences between persons, thereby failing to examine how these variables are associated within individuals on a daily basis. This study examines how daily fluctuations in Personal Standards (PS) perfectionism and Evaluative Concerns (EC) perfectionism relate to each other and to fluctuations in ED symptoms. Adolescents (N = 275) completed questionnaires each evening during seven consecutive days. Multilevel modeling showed significant day-to-day fluctuations in PS and EC perfectionism, and showed that both dimensions are intertwined in the day. Among females, fluctuations in EC perfectionism co-varied with fluctuations in ED symptoms.     

Language deficits in pre-symptomatic Huntington's disease: evidence from Hungarian

A limited number of studies have investigated language in Huntington’s disease (HD). These have generally reported abnormalities in rule-governed (grammatical) aspects of language, in both syntax and morphology. Several studies of verbal inflectional morphology in English and French have reported evidence of over-active rule processing, such as over-suffixation errors (e.g., walkeded) and over-regularizations (e.g., digged). Here we extend the investigation to noun inflection in Hungarian, a Finno-Ugric agglutinative language with complex morphology, and to genetically proven pre-symptomatic Huntington’s disease (pre-HD). Although individuals with pre-HD have no clinical, motor or cognitive symptoms, the underlying pathology may already have begun, and thus sensitive behavioral measures might reveal already-present impairments. Indeed, in a Hungarian morphology production task, pre-HD patients made both over-suffixation and over-regularization errors. The findings suggest the generality of over-active rule processing in both HD and pre-HD, across languages from different families with different morphological systems, and for both verbal and noun inflection. Because the neuropathology in pre-HD appears to be largely restricted to the caudate nucleus and related structures, the findings further implicate these structures in language, and in rule-processing in particular. Finally, the need for effective treatments in HD, which will likely depend in part on the ability to sensitively measure early changes in the disease, suggests the possibility that inflectional morphology, and perhaps other language measures, may provide useful diagnostic, tracking, and therapeutic tools for assessing and treating early degeneration in pre-HD and HD.     

Stress or no stress: mineralocorticoid receptors in the forebrain regulate behavioral adaptation

Corticosteroid effects on cognitive abilities during behavioral adaptation to stress are mediated by two types of receptors. While the glucocorticoid receptor (GR) is mainly involved in the consolidation of memory, the mineralocorticoid receptor (MR) mediates appraisal and initial responses to novelty. Recent findings in humans and mice suggest that under stress, the MR might be involved in the use of different learning strategies. Here, we used male mice lacking the MR in the forebrain (MR(CaMKCre)), which were subjected to 5-10 min acute restraint stress, followed 30 min later by training trials on the circular hole board. Mice had to locate an exit hole using extra- and intra-maze cues. We assessed performance and the use of spatial and stimulus-response strategies. Non-stressed MR(CaMKCre) mice showed delayed learning as compared to control littermates. Prior stress impaired performance in controls, but did not further deteriorate learning in MR(CaMKCre) mice. When stressed, 20-30% of both MR(CaMKCre) and control mice switched from a spatial to a stimulus-response strategy, which rescued performance in MR(CaMKCre) mice. Furthermore, MR(CaMKCre) mice showed increased GR mRNA expression in all CA areas of the hippocampus and an altered basal and stress-induced corticosterone secretion, which supports their role in the modulation of neuroendocrine activity. In conclusion, our data provide evidence for the critical role of MR in the fast formation of spatial memory. In the absence of forebrain MR spatial learning performance was under basal circumstances impaired, while after stress further deterioration of performance was rescued by switching behavior increasingly to a stimulus-response strategy.     

Error reactivity in self-paced performance: Highly-accurate individuals exhibit largest post-error slowing

Reaction time is typically increased following an erroneous response. This post-error slowing is traditionally explained by a strategic adjustment of response threshold towards more conservative behaviour. A recently proposed orienting account provides an alternative explanation for post-error slowing. According to this account, committing an error evokes an orienting response (OR), which inhibits information processing in the subsequent trial, resulting in slow and inaccurate performance. We tested a straightforward prediction of the orienting account in the context of self-paced performance, adopting an individual-differences approach: Post-error slowing should be larger the less frequent an error is. To this end, participants were classified into three groups differing in overall performance accuracy. Larger post-error slowing and stronger post-error accuracy decrease were observed for the high-accuracy group than for the two other groups. Practice pronounced the post-error accuracy decline, especially for the high-accuracy group. The results are consistent with the orienting account of post-error slowing but are problematic for accounts based on strategic evaluation mechanisms.     

Merging on mayday: subgroup and superordinate identification as joint moderators of threat effects in the context of European Union's expansion

Threat has been proposed as an important cause of prejudice with social identification moderating its effects. In the context of the expansion of the European Union, two studies (N = 216 students and N = 107 non‐students) examined how people with different levels of subgroup and superordinate identification respond to threats from an outgroup nested within the same superordinate category as the ingroup. Across experiments, a consistent finding was that participants who strongly identified with the subgroup (Germany) and the superordinate group (Europe) at the same time were most susceptible to a subtle manipulation of threat. Among these participants, threat increased prejudice (Studies 1 and 2) and ingroup projection (Study 2). Findings are discussed with regard to theoretical models of subgroup relations, especially the ingroup projection model, as well as the European integration process. Copyright © 2006 John Wiley & Sons, Ltd.     

Zahnhartsubstanzschäden bei Essstörungen

Eating disorders such as anorexia nervosa and bulimia nervosa lead to several serious physical problems. One possible consequence is acid-related dental erosion. Dental erosion can be identified early and is caused by exogenic (selection of food) and / or endogenic (gastric acid) factors. That is why dentists play an important role in the early identification of eating disorders as well as in the prevention and therapy of dental erosion. They should be important collaborators of psychotherapists. We review characteristic damages to the teeth that are seen in eating disorders as well as preventive and therapeutic interventions. Psychotherapists should be informed about dental problems and preventive strategies to educate their patients.     

Degree of malignancy in multiple sclerosis: clinicopathologic mortality study

Basing on the neuropathologic findings (acute, subacute resp. chronic demyelination) in 58 cases with multiple sclerosis (MS) the determination of the degree of defect in relation to the duration of working capacity and disability has been carried out in comparison with an index made up for progression and malignancy of the disease. In the final phase of illness an acute exacerbation was noteworthy from the morphological point of view in 48.3% of the patients; in these cases was established a hightened index of malignancy. Differences of sex distribution a. o. pointed to a longer lasting defective (chronic) stage in women. The assessment of progression after a five-year period of examination by a limiting malignancy-index allows a probable prognosis to the chances and the risk of the developing process of disease and may be of importance for care.