Assessment of postural control in patients with Parkinson’s disease: Sway ratio analysis

Analysis of the postural stability impairments in neurodegenerative diseases is a very demanding task. Age-related declines in posturographic indices are usually superimposed on effects associated with the pathology and its treatment. We present the results of a novel postural sway ratio (SR) analysis in patients with Parkinson’s disease (PD) and age-matched healthy subjects. The sway ratios have been assessed based upon center of foot-pressure (CP) signals recorded in 55 parkinsonians (Hoehn and Yahr: 1-3) and 55 age-matched healthy volunteers while standing quiet with eyes open (EO) and then with eyes closed (EC). Complementing classical sway measure abnormalities, the SR exhibited a high discriminative power for all controlled factors: pathology, vision, and direction of sway. Both the anteroposterior (AP) and mediolateral (ML) sway ratios were significantly increased in PD patients when compared to the control group. An additional SR increase was observed in the response to eyes closure. The sway ratio changes documented here can be attributed to a progressive decline of a postural stability control due to pathology. In fact, a significant correlation between the mediolateral SR under EO conditions and Motor Exam (section III) score of the UPDRS was found. The mediolateral sway ratios computed for EO and EC conditions significantly correlated with the CP path length (r = .87) and the mean anteroposterior CP position within the base of support (r = .38). Both indices reflect postural stability decline and fall tendency # in parkinsonians. The tremor-type PD patients (N = 34) showed more pronounced relationships between the mediolateral SR and selected items from the UPDRS scale, including: falls (Kendall Tau = .47, p < .05), rigidity (.45, p < .05), postural stability (retropulsion) (.52), and the Motor Exam score (.73). The anteroposterior SR correlated only with tremor (Kendal Tau = .77, p < .05). It seems that in force plate posturography the SR can be recommended as a single reliable measure that allows for a better quantitative assessment of postural stability impairments.     

Emotion-induced retrograde amnesia and trait anxiety

Emotional arousal can both enhance and impair memory. Considering that both emotional memory and trait anxiety (TA) have been associated with adrenergic activity, the authors investigated whether there is an association between 2 opposite emotional memory biases and the TA. The authors used a procedure recently put forward by B. A. Strange, R. Hurlemann, and R. J. Dolan (2003) to elicit an emotion-induced retrograde amnesia (ERA) coupled to an emotional memory enhancement (EME). The authors contrasted the association between these emotional memory biases and the TA in several conditions involving different levels of encoding and types of recall. The results presented here indicated a significant interaction of the TA with EME and ERA and the dependency of these biases on the consciously controlled use of memory.     

Self-serving biases: The role of perspective-taking

This research explores the role of perspective taking in self-serving biases. Assisted by a confederate, 80 subjects performed an impression-formation task and were given either success or failure bogus feedback. One week later, half of the subjects watched their performance on videotape and provided causal attributions (‘observers’). The other half simply gave causal attributions (‘actors’). Thus, the experiment employed a modified version of the actor/observer paradigm with one group of subjects taking the perspective of observers (‘observers’) and one group of subjects keeping their original perspective (‘actors’). The aim of this study was to test whether the change of perspective would increase dispositional causal attributions both in success and failure conditions. Results showed that subjects gave greater causal weight to internal factors (ability, effort) and less causal weight to external factors (task characteristics, collaboration with the partner) in the success than in the failure condition. Moreover, in a direct comparison task, subjects attributed a greater percentage of responsibility to themselves than to their partner in the success than in the failure condition. However, the type of perspective produced no significant effects, but showed an attenuation of self-serving biases for observers as compared to actors. A motivational explanation of the results is proposed.     

Mobilizing cause supporters through group‐based interaction

Collective action expresses group‐based identities, formed by supporters seeking to further particular social causes. While the development of groups linked to action necessitates interaction among supporters, little research has examined how these groups form. Utilizing responses of supporters who participated in 1 of 29 action‐planning sessions, this research presents an initial attempt to identify the ingredients important to this process. It shows that to the extent that the actions agreed on in the course of group interactions were seen as capable of making a difference (action efficacy), and worthy of public expression (action voice), supporters’ group‐based identification was enhanced. This in turn increased their willingness to engage in collective action. Practical implications and avenues for future research to understand the mobilization process are discussed.     

Squares in Fork Arrow Logic

In this paper we show that the class of fork squares has a complete orthodox axiomatization in fork arrow logic (FAL). This result may be seen as an orthodox counterpart of Venema's non-orthodox axiomatization for the class of squares in arrow logic. FAL is the modal logic of fork algebras (FAs) just as arrow logic is the modal logic of relation algebras (RAs). FAs extend RAs by a binary fork operator and are axiomatized by adding three equations to RAs equational axiomatization. A proper FA is an algebra of relations where the fork is induced by an injective operation coding pair formation. In contrast to RAs, FAs are representable by proper ones and their equational theory has the expressive power of full first-order logic. A square semantics (the set of arrows is U×U for some set U) for arrow logic was defined by Y. Venema. Due to the negative results about the finite axiomatizability of representable RAs, Venema provided a non-orthodox finite axiomatization for arrow logic by adding a new rule governing the applications of a difference operator. We address here the question of extending the type of relational structures to define orthodox axiomatizations for the class of squares. Given the connections between this problem and the finitization problem addressed by I. Németi, we suspect that this cannot be done by using only logical operations. The modal version of the FA equations provides an orthodox axiomatization for FAL which is complete in view of the representability of FAs. Here we review this result and carry it further to prove that this orthodox axiomatization for FAL also axiomatizes the class of fork squares.     

Role of psychosocial risk factors in predicting maternal and paternal depressive symptomatology during pregnancy

The aim of the present study was to investigate the role of several psychosocial risk factors in predicting depressive symptomatology during pregnancy in mothers and fathers, respectively. A total of 146 primiparous mothers and 105 primiparous fathers reporting a psychosocial risk condition were recruited independently from maternity and child health services, during the second trimester of pregnancy. All parents were evaluated for depressive symptomatology, anxiety, and perceived social support. Two hierarchical multiple regression analyses were performed to determine the role of psychosocial factors in predicting depressive symptomatology during pregnancy, in mothers and fathers. Marital dissatisfaction, personal history of depression, and personal trait anxiety were identified as significant predictors of depressive symptomatology during pregnancy, both in mothers and in fathers. Family history of substance abuse, conflictual relationship with the parents in the past year, and bereavement in the past year were identified as significant factors contributing to elevated depressive symptoms during pregnancy in mothers, but not fathers. In this study, several psychosocial risk factors were consistently related to an increase in maternal and paternal depressive symptoms during pregnancy; some of these factors seem to be specifically related to maternal depressive mood.     

Executive Functions in School‐age Children: Influence of Age,Gender, School Type and Parental Education

Summary: This study aimed to evaluate whether age, gender, type of school and parental education could predict executive performance in school‐age children. Unconstrained, phonemic and semantic verbal fluency tasks (n = 402), as well as the Hayling Sentence Completion Test (n = 275) and the Random Number Generation task (n = 274) were administered to typically developing 6‐to‐12‐year‐old children. A hierarchical regression analysis was performed (p ≤ 0.05). The most significant explanatory models involved child age and parental education, as well as these two variables in addition to the type of school attended by the child. The main individual predictors of executive performance were age and school type. These results may be related to structural and functional alterations in the brain, an increased repertoire of cognitive strategies, the effects of education and the intensity of environmental cognitive stimulation. These findings may contribute to the development of stimulation and intervention programs for EF in clinical and educational settings.Copyright © 2017 John Wiley & Sons, Ltd.