Are Older Adults More Dependent on Visual Information in Regulating Self-Motion Than Younger Adults?

Older adults look at the ground more while they are walking than younger adults do. In the present study, the effect of blocking that exproprioceptive visual information on the walking pattern of older adults was investigated. The first 0.75 m of the floor in front of healthy young adults (n = 10, mean age = 26.0 years) and 2 groups of older adults (n = 10, mean age 65.7 years; and n = 9, mean age = 75.9 years) was occluded. The dependent variables were step velocity, step length, and step frequency. The effect of the manipulation on those kinematic variables increased with age. The older adults had a significant increase in velocity and step length. The possible use of optic flow information from the ground to regulate the velocity of self-motion is discussed.     

Hilbert's Programs and Beyond

Pour résoudre les paradoxes bien connus de la mécanique quantique, on propose une interprétation par ramification (ou univers parallèles) analogue à celle d’Everett, mais avec des différences: (i) on propose une infinité continue de branches, dont les poids (o[ugrave] probabilités) se calculent par intégrale; (ii) les branches sont séparées par des ramifieurs qui se propagent à la vitesse de la lumière. Lorsqu’est négligeable la composante d’énergie négative de la fonction d’onde, le poids de chaque branche en un point donné u est égal au flux du quadrivecteur (courant-densité de présence), soit à travers l'élément d’écran antérieur à u sur lequel l'impact est perçu, soit à travers le cône passé de u si aucun impact n’est perçu.

In order to solve well-known paradoxes in quantum mechanics, we propose a reworking of Everett's interpretation with ramified branches (or many worlds), yet somewhat different: (i) branches form an infinity continuum and each weight (probability) is defined by an integral; (ii) branches are separated by ramifiers which propagate themselves with the velocity of light. Assuming we can neglect the negative-energy component in the wave function, then the weight of each branch at a given point u is equal to the flux of the quadrivector (current-presence density), either through the screen element where the impact occurs, or through the past light-cone of u if no impact occurs.     

‘Metamathematics’ in Transition

In this paper, we trace the conceptual history of the term ‘metamathematics’ in the nineteenth century. It is well known that Hilbert introduced the term for his proof-theoretic enterprise in about 1922. But he was verifiably inspired by an earlier usage of the phrase in the 1870s. After outlining Hilbert's understanding of the term, we will explore the lines of inducement and elucidate the different meanings of ‘metamathematics’ in the final decades of the nineteenth century. Finally, we will investigate the earlier occurrences and come to the conclusion that the conceptual prehistory of the Hilbertian notion of metamathematics dates back to 1870, whereas the history of the word starts in 1799 at the latest.

What is this: metamathematics? It is something amazing everybody, […] since it makes the mind dizzy and withdraws thinking its sole fulcrum.1 ¹ Brunner 1898, p. 832: ‘Was ist das: Metamathematik? Es ist etwas, was einen Jeden in das äusserste Staunen versetzt, […] was das Gehirn schwindlig macht und dem Denken seinen einzigen Stütz- und Angelpunkt zu entziehen droht’.      

Adolescent ethnic prejudice: understanding the effects of parental extrinsic versus intrinsic goal promotion

Based on Self-Determination Theory, the role of parental extrinsic versus intrinsic (E / I) goal promotion for adolescent ethnic prejudice and the mechanisms underlying this effect were examined in a sample of adolescents and their parents. Results indicate that paternal and maternal E / I goal promotion had a significantly positive effect on ethnic prejudice. This effect could be accounted for by differences in adolescent right-wing authoritarianism (RWA) and social dominance orientation (SDO). In addition, differences in adolescent E / I goal pursuit fully mediated the effects of parental E / I goal promotion on RWA and SDO. Finally, the effects of adolescent E / I goal pursuits on ethnic prejudice were fully mediated by RWA and SDO. Implications of these findings will be discussed.     

Emerging Adulthood and Leaving Foster Care: Settings Associated with Mental Health

The present study examined the role of contextual support on mental health during the transition to adulthood within a vulnerable group, adolescents leaving foster care because of their age. Participants were 265 19- to 23-year-olds who retrospectively reported on 3 main contexts of emerging adulthood: housing security, educational achievement, and employment attainment in the first 2 years after leaving foster care. Mental health measured self-reported emotional distress, substance abuse, and deviancy at the time of interview. Growth Mixture Modeling empirically identified 3 latent trajectory classes. Stable-Engaged (41%) experienced secure housing and increasing connections to education and employment over time. Stable-Disengaged (30%) maintained housing but reported decreasing rates of education and small increases in employment. Instable-Disengaged (29%) experienced chronic housing instability, declined connection to education, and failed to attain employment. Stable-Engaged and Stable-Disengaged classes reported better mental health compared to the Instable-Disengaged class, indicating the importance of housing in transitioning to adulthood.     

The role of depressogenic personality and attachment in the intergenerational similarity of depressive symptoms: a study with early adolescents and their mothers

Parental depression has been identified as a risk factor for psychopathology in children, and for child depression in particular. Increasingly, research is addressing the underlying psychological processes that may explain the intergenerational similarity of depressive symptoms. In the present study, we aim to investigate the role of two theoretically relevant vulnerability factors in this intergenerational similarity, that is, (a) dimensions of depressogenic personality (i.e., sociotropy and autonomy) and (b) dimensions of attachment (i.e., anxiety and avoidance). Results in a sample of early adolescents and their mothers show significant intergenerational similarity in both sets of vulnerabilities. Moreover, the intergenerational similarity of both vulnerability factors was found to account for the association between mothers' and children's depressive symptoms. Within each generation there were also meaningful and specific associations between dimensions of depressogenic personality and dimensions of attachment, with sociotropy being primarily related to anxiety and with autonomy being primarily related to avoidance.     

The effect of a non-steroidal anti-inflammatory drug on two important predictors for accidental falls: Postural balance and manual reaction time. A randomized, controlled pilot study

Accidental falls in older individuals are a major health and research topic. Increased reaction time and impaired postural balance have been determined as reliable predictors for those at risk of falling and are important functions of the central nervous system (CNS). An essential risk factor for falls is medication exposure. Amongst the medications related to accidental falls are the non-steroidal anti-inflammatory drugs (NSAIDs). About 1-10% of all users experience CNS side effects. These side effects, such as dizziness, headaches, drowsiness, mood alteration, and confusion, seem to be more common during treatment with indomethacin. Hence, it is possible that maintenance of (static) postural balance and swift reactions to stimuli are affected by exposure to NSAIDs, indomethacin in particular, consequently putting older individuals at a greater risk for accidental falls. The present study investigated the effect of a high indomethacin dose in healthy middle-aged individuals on two important predictors of falls: postural balance and reaction time. Twenty-two healthy middle-aged individuals (59.5 ± 4.7 years) participated in this double-blind, placebo-controlled, randomized crossover trial. Three measurements were conducted with a week interval each. A measurement consisted of postural balance as a single task and while concurrently performing a secondary cognitive task and reaction time tasks. For the first measurement indomethacin 75 mg (slow-release) or a visually identical placebo was randomly assigned. In total, five capsules were taken orally in the 2.5 days preceding assessment. The second measurement was without intervention, for the final one the first placebo group got indomethacin and vice versa. Repeated measures GLM revealed no significant differences between indomethacin, placebo, and baseline in any of the balance tasks. No differences in postural balance were found between the single and dual task conditions, or on the performance of the dual task itself. Similarly, no differences were found on the manual reaction time tasks. The present study showed that a high indomethacin dose does not negatively affect postural balance and manual reaction time in this healthy middle-aged population. Although the relatively small and young sample limits the direct ability to generalize the results to a population at risk of falling, the results indicate that indomethacin alone is not likely to increase fall risk, as far as this risk is related to abovementioned important functions of the CNS, and not affected by comorbidities.     

Dimensions and Correlates of Attention Deficit/Hyperactivity Disorder and Sluggish Cognitive Tempo

The present study examined Sluggish Cognitive Tempo (SCT) in relation to ADHD symptoms, clinical diagnosis, and multiple aspects of adjustment in a clinical sample. Parent and teacher reports were gathered for 322 children and adolescents evaluated for behavioral, emotional, and/or learning problems at a university clinic. Confirmatory factor analyses (CFA) supported the presence of three separate, but correlated factors (SCT, inattention, and hyperactivity/impulsivity) in both parent and teacher ratings. As expected, SCT symptoms were greatest in youth with ADHD Inattentive type, but were also found in non-ADHD clinical groups. SCT symptoms were related to inattention, internalizing, and social problems across both parent and teacher informants; for parent reports, SCT was also related to more externalizing problems. Findings support the statistical validity of the SCT construct, but its clinical utility is still unclear.