Dynamic stability control during perturbed walking can be assessed by a reduced kinematic model across the adult female lifespan

The current study aimed to determine potential differences in dynamic stability control during perturbed walking across the adult female lifespan and to test the hypothesis that such differences can be assessed by a reduced kinematic model. 11 young-aged (22–30 years), 9 middle-aged (41–59 years) and 14 old-aged (62–75 years) female adults walked on a treadmill while the right leg was unexpectedly perturbed once during the swing phase. Margin of stability (MS) at touchdown was investigated using a full body and a reduced kinematic model. After the perturbation, all age groups showed a lower MS compared to non-perturbed gait (baseline), leading to negative MS. Four old-aged adults failed to cope with the task (only preventing a fall by grasping). The remaining ten old-aged and the middle-aged subjects required three more recovery steps than the young-aged adults to get back to baseline MS. Moreover, there were no differences between kinematic models, and both methods demonstrated similar age-related findings. We concluded that the ability to control dynamic stability during perturbed walking by enlarging the base of support has already begun to deteriorate by middle age. Further, the valid agreement between kinematic models shows that such differences can be assessed by using just four body markers.     

Exploring Similarities and Differences in Personal Epistemologies of U.S. and German Elementary School Teachers

The current study examines the personal epistemology of fourth-grade elementary school teachers from Germany (n = 10) and the United States (n = 10) to gain a more nuanced understanding of teachers’ beliefs about knowledge and knowing through a cross-cultural lens. Analyses of semi-structured interviews reveal similarities and differences in the statements of teachers. Four themes are identified: The majority of teachers believed that (a) knowing is uncertain and (b) knowledge has domain-specific qualities; (c) U.S. teachers seemed to view knowledge more as being embedded within their community, while (d) German teachers discussed more internal knowledge sources. The general discussion includes possible cross-cultural explanations for these four emerging themes and points tentatively to developmental issues stemming from uncertainty beliefs. Conceptual and educational implications are discussed and suggestions for future research are given.     

Pseudocontingencies derived from categorically organized memory representations

Pseudocontingencies (PCs) allow for inferences about the contingency between two variables X and Y when the conditions for genuine contingency assessment are not met. Even when joint observations X _i and Y _i about the same reference objects i are not available or are detached in time or space, the correlation r(X _i ,Y _i ) is readily inferred from base rates. Inferred correlations are positive (negative) if X and Y base rates are skewed in the same (different) directions. Such PC inferences afford useful proxies for actually existing contingencies. While previous studies have focused on PCs due to environmental base rates, the present research highlights memory organization as a natural source of PC effects. When information about two attributes X and Y is represented in a hierarchically organized categorical memory code, as category-wise base rates p(X) and p(Y), the reconstruction of item-level information from category base rates will naturally produce PC effects. Three experiments support this contention. When the yes base rates of two respondents in four questionnaire subscales (categories) were correlated, recalled and predicted item-level responses were correlated in the same direction, even when the original responses to specific items within categories were correlated in the opposite direction.     

Evidence for Implicit Learning in Syntactic Comprehension

This study provides evidence for implicit learning in syntactic comprehension. By reanalyzing data from a syntactic priming experiment (Thothathiri & Snedeker, 2008), we find that the error signal associated with a syntactic prime influences comprehenders' subsequent syntactic expectations. This follows directly from error‐based implicit learning accounts of syntactic priming, but it is unexpected under accounts that consider syntactic priming a consequence of temporary increases in base‐level activation. More generally, the results raise questions about the principles underlying the maintenance of implicit statistical knowledge relevant to language processing, and about possible functional motivations for syntactic priming.     

Visual image retention does not contribute to modulation of event-related potentials by mental rotation

Rotation of a visual image in mind is associated with a slow posterior negative deflection of the event-related potential (ERP), termed rotation-related negativity (RRN). Retention of a visual image in short-term memory is also associated with a slow posterior negative ERP, termed negative slow wave (NSW). We tested whether short-term memory retention, indexed by the NSW, contributes to the RRN. ERPs were recorded in the same subjects in two tasks, a mental rotation task, eliciting the RRN, and a visual short-term memory task, eliciting the NSW. Over both right and left parietal scalp, no association was found between the NSW and the RRN amplitudes. Furthermore, adjusting for the effect of the NSW had no influence on a significant association between the RRN amplitude and response time, an index of mental rotation performance. Our data indicate that the RRN reflects manipulation of a visual image but not its retention in short-term memory.     

What Harmony Could and Could Not Be

The notion of harmony has played a pivotal role in a number of debates in the philosophy of logic. Yet there is little agreement as to how the requirement of harmony should be spelled out in detail or even what purpose it is to serve. Most, if not all, conceptions of harmony can already be found in Michael Dummett's seminal discussion of the matter in The Logical Basis of Metaphysics. Hence, if we wish to gain a better understanding of the notion of harmony, we do well to start here. Unfortunately, however, Dummett's discussion is not always easy to follow. The following is an attempt to disentangle the main strands of Dummett's treatment of harmony. The different variants of harmony as well as their interrelations are clarified and their individual shortcomings qua interpretations of harmony are demonstrated. Though no attempt is made to give a detailed alternative account of harmony here, it is hoped that our discussion will lay the ground for an adequate rigorous treatment of this central notion.     

The anxiety buffering function of close relationships: mortality salience effects on the readiness to compromise mate selection standards

This research examines the utility of a terror management approach to understanding the motivations and emotional consequences of compromise in mate selection. One hundred and sixty‐eight undergraduates completed a self‐esteem scale and a scale tapping ideal mate characteristics, and were then assigned either to a mortality salience, physical pain salience, or neutral condition. Half of the participants rated their readiness to compromise ideal mate standards and the remaining half completed a neutral scale. Then, participants completed a scale tapping their emotional state. Mortality salience led participants to significantly compromise their mate requirements. This effect seemed to be most pronounced among high self‐esteem participants who also experienced the greatest amount of guilt when compromising under mortality salient conditions. Low self‐esteem participants who compromised under mortality salient conditions reacted with higher levels of shame. The results are discussed in terms of the anxiety buffering functions of close relationships. Copyright © 2002 John Wiley & Sons, Ltd.     

The Proposition of a General Version of the Theory of Planned Behavior: Predicting Ecological Behavior1

The present paper explores whether the theory of planned behavior (TPB) must abandon the notion that perceived behavioral control (PBC) has a direct influence on behavior. In a cross‐sectional survey of 895 Swiss residents, our hypothesis was tested by means of structural equation models. Applied specifically, PBC turned out to be a significant direct predictor of one's performance. A general version of the TPB based on aggregated measures, however, revealed PBC's direct influence on behavior to be nonsignificant and, presumably, a non‐universally applicable and thus nongeneralizable part of the theory. Intention determined 51% to 52% of people's ecological behavior, which supports the claim of a strong attitude‐behavior relation. Attitude, subjective norms, and PBC, the 3 TPB components, account for 81% of intention's variance.     

Habitualität als Potentialität: Zur Konkretisierung des Ich bei Husserl

Ohne Zusammenfassung