Examining parental stress and its link to hair cortisol and DHEA levels in kindergartners.

BACKGROUND: Parental work-family conflict (WFC) and parental household income have been linked to negative outcomes for children. So far, no study has associated these two stressors with the hair concentration of cortisol (HCC) and dehydroepiandrosterone (DHEA) in kindergarteners as a measurement of their objective stress. METHODS AND MEASURES: 44 children (40.91% female) with a mean age of 5.16 years and their parents participated in this cross-sectional study. Children's cortisol and DHEA measurements reflected the hormones produced over the past two months. Parents filled out questionnaires concerning their WFC and parenting behavior. RESULTS: Higher maternal WFC and a lower parental net household income were negatively associated with the DHEA and positively with HCC/DHEA ratio of their children. No significant associations were found between HCC and any included variables. Paternal WFC had no impact on the stress hormones and negatively affected parenting behavior of both parents. Levels of stress hormones were not correlated with parenting behavior. CONCLUSION: The present results indicated a higher stress exposure in children of mothers with a higher WFC and lower net household income. Conceivably, this may have led to an accumulation of allostatic load. Potential influences of demographic variables on the children's hormones are discussed.

SensAA-Design and Verification of a Cloud-Based Wearable Biomechanical Data Acquisition System.

Exoskeletons designed to assist patients with activities of daily living are becoming increasingly popular, but still are subject to research. In order to gather requirements for the design of such systems, long-term gait observation of the patients over the course of multiple days in an environment of daily living are required. In this paper a wearable all-in-one data acquisition system for collecting and storing biomechanical data in everyday life is proposed. The system is designed to be cost efficient and easy to use, using off-the-shelf components and a cloud server system for centralized data storage. The measurement accuracy of the system was verified, by measuring the angle of the human knee joint at walking speeds between 3 and 12 km/h in reference to an optical motion analysis system. The acquired data were uploaded to a cloud database via a smartphone application. Verification results showed that the proposed toolchain works as desired. The system reached an RMSE from 2.9° to 8°, which is below that of most comparable systems. The system provides a powerful, scalable platform for collecting and processing biomechanical data, which can help to automize the generation of an extensive database for human kinematics.

Elevated EEG heartbeat-evoked potentials in adolescents with more ADHD symptoms.

INTRODUCTION: Symptoms of attention deficit hyperactivity disorder (ADHD) are associated with a variety of mental abnormalities, but little is known about the perception and processing of internal signals, i.e., interoception, in individuals with ADHD symptoms. This study aimed to investigate the association between ADHD symptoms and the heartbeat-evoked potential (HEP), known as a neural correlate of automatic interoceptive processing of cardiac signals, in adolescents. METHODS: HEPs of 47 healthy adolescent participants (53.2 % female) with a mean age of 14.29 years were measured during an emotional face recognition task. In addition, participants completed a self-report screening for ADHD symptoms. RESULTS: ADHD symptoms were positively related to the HEP activity during the task in three of eight EEG sectors in the left hemisphere, as well as in all sectors in the right hemisphere. DISCUSSION: This study is the first to demonstrate preliminary a relationship between the strength of HEP activity and ADHD symptoms in awake subjects. This finding of higher HEP amplitudes in subjects with more ADHD symptoms can be interpreted in terms of (i) increased arousal, (ii) altered neural processing of internal processes in an emotion-relevant task, and (iii) a misaligned precision-weighting process of task-irrelevant stimuli according to the predictive coding framework. These different interpretations could be reflected by previous studies showing heterogeneity of psychological deficits in individuals with ADHD symptoms. However, the generalizability to patients with diagnosed ADHD is limited due to the measurement tool for ADHD symptoms and the sample characteristics.