Using the variability of continuous relative phase as a measure to discriminate between healthy and injured runners

Several studies have used variability of continuous relative phase (CRP) to investigate overuse injuries, since low variability is thought to be related to running injuries. This study investigates whether the analysis of CRP variability leads to additional information about possible differences or similarities between healthy and injured runners. Further, a decision about future applications of CRP variability should be based on the ability to implement and interpret data. 18 healthy female runners (CO) and 18 female runners who suffered from iliotibial band syndrome (ITBS) were evaluated by calculating CRP variability for 4 coupling pairs. Besides analyzing continuous variability of CRP, we also averaged it for the whole stance phase and for four predefined stance phase intervals. Confidence intervals were displayed and independent t-tests for comparing the two groups were conducted. During initial and terminal stance phase as well as after heel-off an increase in CRP variability was detected for both groups of runners. In contrast, the foot flat period was characterized by stable joint coordination and a decrease in variability. This paper presents possible interpretations of CRP variability but no statistically significant differences in CRP variability were found between the two groups of runners. Despite the missing statistical significance, a relationship between high CRP variability and injury seems to be conceivable, since the injured runners demonstrated an increased variability for all couplings in the first half of the stance phase. Further application of CRP variability in biomechanical research is essential to determine whether a relationship exists between injury and coordination variability.     

Brain-to-brain coupling: a mechanism for creating and sharing a social world

Cognition materializes in an interpersonal space. The emergence of complex behaviors requires the coordination of actions among individuals according to a shared set of rules. Despite the central role of other individuals in shaping one's mind, most cognitive studies focus on processes that occur within a single individual. We call for a shift from a single-brain to a multi-brain frame of reference. We argue that in many cases the neural processes in one brain are coupled to the neural processes in another brain via the transmission of a signal through the environment. Brain-to-brain coupling constrains and shapes the actions of each individual in a social network, leading to complex joint behaviors that could not have emerged in isolation.     

Dual-tasking alleviated sleep deprivation disruption in visuomotor tracking: an fMRI study

Effects of dual-responding on tracking performance after 49-h of sleep deprivation (SD) were evaluated behaviorally and with functional magnetic resonance imaging (fMRI). Continuous visuomotor tracking was performed simultaneously with an intermittent color-matching visual detection task in which a pair of color-matched stimuli constituted a target and non-matches were non-targets. Tracking error means were binned time-locked to stimulus onset of the detection task in order to observe changes associated with dual-responding by comparing the error during targets and non-targets. Similar comparison was made with fMRI data. Our result showed that despite a significant increase in the overall tracking error post SD, from 20 pixels pre SD to 45 pixels post SD, error decreased to a minimum of about 25 pixels 0-6s after dual-response. Despite an overall reduced activation post SD, greater activation difference between targets and non-targets was found post SD in task-related regions, such as the left cerebellum, the left somatosensory cortex, the left extrastriate cortex, bilateral precuneus, the left middle frontal gyrus, and the left motor cortex. Our results suggest that dual-response helps to alleviate performance impairment usually associated with SD. The duration of the alleviation effect was on the order of seconds after dual-responding.     

Family relations, mental health and adherence to nutritional guidelines in patients facing dialysis initiation

This study investigated the effect of family relations on patients' adjustment to dialysis. The two main aims were to develop a family typology, and to explore the influence of family profile on the patient's anxiety, depression and adherence to nutritional guidelines. The sample consisted of 120 patients (mean age 63 years; 67.5% of men). They completed several measures 1, 6 and 12 months after dialysis initiation. The scales used were the Family Relationship Index and the Hospital Anxiety and Depression Scale. Perceived adherence to nutritional guidelines was assessed using two visual analogical scales. Results showed that family relations remained stable over time. Cluster analysis yielded three family profiles, which were named conflict, communicative and supportive families. Patients belonging to conflict families perceived themselves as less adhering to nutritional guidelines. For these patients, anxiety and depressive moods increased significantly over time, whereas mental health remained stable over time for communicative and supportive families. This research underlines that family relations are essential in global consideration of the care of patients treated by dialysis. Conflict families seem especially at risk. They should be identified early to help them adapt to this stressful treatment.     

Persuasion or Alignment?

Persuasion is a fact of social life, one upon which positive and negative views can be taken. Argumentative rhetoric is often functionally defined as aiming to persuade. Different views on persuasion are taken in argumentative studies, and many other disciplines focus on persuasion. This article takes an “inter-discursive” view of argumentation, and, following the “Hamblin’s trend”, suggests a possible replacement for the concept of persuasion by the inter-discursive concept of alignment.     

Protecting Against Low‐Probability Disasters: The Role of Worry

We carry out a large monetary stakes insurance experiment with very small probabilities of losses and ambiguous as well as exact probabilities. Many individuals do not want to pay anything for insurance whether the probabilities are given exactly or are ambiguous. Many others, however, are willing to pay surprisingly large amounts. With ambiguity, the percentage of those paying nothing is smaller and the willingness to pay (WTP) of the other individuals larger than with exact probabilities. Comparing elasticities with ambiguity, we find that worry is much more important than subjective probability in determining WTP for insurance. Furthermore, when the ambiguous loss probability is increased by a factor of 1000, it has almost no effect on WTP. Copyright © 2011 John Wiley & Sons, Ltd.     

Human visual short-term memory precision can be varied at will when the number of retained items is low

It has been debated whether human visual working memory is limited by the number of items or the precision with which they are represented. In the research reported here, we show that the precision of working memory can be flexibly and willfully controlled, but only if the number of retained items is low. Electroencephalographic recordings revealed that a neural marker for visual working memory (contralateral delay activity, or CDA) that is known to increase in amplitude with the number of retained items was also affected by the precision with which items were retained. However, willfully enhanced precision increased CDA amplitude only when the number of retained items was low. These results show that both the number and the (willfully controlled) precision of retained items constrain visual working memory: People can enhance the precision of their visual working memory, but only for a few items.     

Anxiety and Depression in Patients with Amyotrophic Lateral Sclerosis and Their Caregivers

A large number of studies have investigated a variety of psychological aspects in people with Amyotrophic Lateral Sclerosis, but there is still considerable uncertainty concerning the actual morbidity, in particular for anxiety. We aim to evaluate depression levels and anxiety disposition in ALS patients and their caregivers, in comparison to healthy controls. We conducted a cross-sectional comparison between people with ALS, their caregivers and a non-clinical control group in order to evaluate anxiety and depression levels. 40 ALS patients, their caregivers and 40 healthy adult subjects completed the Beck Depression Inventory II (BDI-II) and the State-Trait Anxiety Inventory—Y2 scale (STAI). We compared overall and single item scores in order to find differences between the three groups. BDI-II scores were significantly different between groups. Depression scores were higher for patients than for healthy controls, in both somatic and psychological sub-scales. Caregivers presented higher levels of psychological depression in comparison with healthy controls, and lower scores of somatic depression in comparison to patients. No differences were found in trait anxiety levels comparing the three groups. ALS patients and their caregivers developed more depression related symptomatology than the non-clinical sample. However, susceptibility to anxiety for both patients and caregivers seemed to be at a normal level.     

Sex differences of salivary cortisol secretion in patients with major depression

Depression is associated with increased cortisol secretion and occurs more often in women than in men. Thus, it has been hypothesized that differences in cortisol secretion might, in part, be responsible for the greater risk of developing depression in women. However, only few studies have examined sex differences in baseline cortisol secretion in depressed patients and healthy controls. We examined sex effects on cortisol secretion in 52 medication-free patients with major depression (37 women, 15 men, mean ± SD age 35 ± 11 years, Hamilton Depression Scale mean score 27 ± 5) and 50 healthy age- and sex-matched control subjects. Salivary cortisol concentrations were measured at 8:00, 12:00, 16:00, and 22:00 h. Repeated measures analysis of covariance revealed a group × sex interaction (p = 0.05). Post hoc tests revealed higher cortisol concentrations in depressed compared to healthy men [F(1;29) = 7.5, p = 0.01]. No differences were found between depressed and non-depressed women. Our results do not support the hypothesis that differences in cortisol secretion between depressed and non-depressed subjects are more pronounced in women than in men. Study characteristics and methods as well as sex-specific confounding variables such as menstrual cycle, menopause and the use of oral contraceptives may account for inconclusive results across studies.