Perceiving nonverbal behavior: Neural correlates of processing movement fluency and contingency in dyadic interactions

Despite the fact that nonverbal dyadic social interactions are abundant in the environment, the neural mechanisms underlying their processing are not yet fully understood. Research in the field of social neuroscience has suggested that two neural networks appear to be involved in social understanding: (1) the action observation network (AON) and (2) the social neural network (SNN). The aim of this study was to determine the differential contributions of the AON and the SNN to the processing of nonverbal behavior as observed in dyadic social interactions. To this end, we used short computer animation sequences displaying dyadic social interactions between two virtual characters and systematically manipulated two key features of movement activity, which are known to influence the perception of meaning in nonverbal stimuli: (1) movement fluency and (2) contingency of movement patterns. A group of 21 male participants rated the “naturalness” of the observed scenes on a four‐point scale while undergoing fMRI. Behavioral results showed that both fluency and contingency significantly influenced the “naturalness” experience of the presented animations. Neurally, the AON was preferentially engaged when processing contingent movement patterns, but did not discriminate between different degrees of movement fluency. In contrast, regions of the SNN were engaged more strongly when observing dyads with disturbed movement fluency. In conclusion, while the AON is involved in the general processing of contingent social actions, irrespective of their kinematic properties, the SNN is preferentially recruited when atypical kinematic properties prompt inferences about the agents' intentions. Hum Brain Mapp 35:1362–1378, 2014. © 2013 Wiley Periodicals, Inc.     

Does skin-to-skin contact reduce stress during diaper change in preterm infants?

Background

Skin-to-skin contact reduces pain response in preterm infants subjected to minor painful procedures, such as heel lance. Diaper change is a procedure performed several times daily in hospitalized preterm infants. Routine care giving tasks such as diaper change may be stressful for the infant.

Aims

The purpose of this study was to investigate whether diaper change induces stress and if skin-to-skin contact could reduce such stress, measured by changes in skin conductance.

Study design

This was a randomized crossover pilot study in 19 preterm infants with gestational age between 28 and 34 weeks. The diaper change procedure was done twice in each infant, once during skin-to-skin contact, and once in incubator or bed with the mother present.

Outcome measures

During diaper change heart rate (HR), peripheral oxygen saturation (SpO₂), and changes in skin conductance (SC) peaks per sec, using the Skin Conductance Algesimeter (SCA), were registered.

Results

The mean SC peaks/sec increased/decreased significantly under/after change of diapers which thereby underpins that this is a stressful procedure for the preterm infant.Skin-to-skin contact (SSC) entails significantly lower stress levels (p < 0.05) compared to diaper changed in an incubator/bed measured by the SCA.

Conclusions

Diaper change is a stressful procedure for preterm infants and may be ameliorated by skin-to-skin contact.     

Microglial cell population dynamics in the injured adult central nervous system

Reactive microgliosis is characteristic of trauma and stroke as well as inflammatory and chronic neurodegenerative disease. A conspicuous feature of the microglial reaction to acute neural injury is a massive expansion of the microglial cell population which peaks a few days following injury. New data based on the use of radiation bone marrow-chimeric mice suggest this expansion also involves recruitment of bone marrow-derived cells, which migrate into the neural parenchyma and differentiate into microglia. Here, we discuss the contribution of bone marrow-derived cells to the injury-induced expansion of the microglial cell population, seen in the dentate gyrus with ongoing anterograde axonal and terminal synaptic degeneration, subsequent to transection of the entorhino-dentate perforant path projection. In this paradigm of minor brain injury, the bone marrow-derived cells are grossly outnumbered by activated resident microglia, which express the stem cell antigen CD34 concurrent to a marked capacity for self-renewal. The observation of a mixed origin of lesion-reactive microglia, consisting of a smaller subpopulation of exogenous bone marrow-derived microglia, and a larger population of activated resident microglia, the majority of which express CD34 and undergo proliferation, suggests that lesion-reactive microglia consist of functionally distinct cell populations. The demonstration of an injury-enhanced recruitment of bone marrow-derived cells into the perforant path-denervated dentate gyrus, raises the possibility of using genetically manipulated cells as vectors for lesion-site-specific gene therapy even in minimally injured areas of the central nervous system.     

Stroke-Related Knowledge and Lifestyle Behavior among Stroke Survivors

Aims: Awareness of stroke symptoms and risk factors, and actions taken in order to reduce the risk of new stroke events, should be of great importance among stroke survivors. The aims of this study were to assess changes in stroke-related knowledge and lifestyle behavior among patients experiencing a cerebrovascular event, and to assess the agreement between the patients’ self-reported diagnosis, and the discharge diagnosis. Methods: All patients discharged with a diagnosis of stroke or transient ischemic attack during a 1-year period, received postal survey questionnaires at 3 and 12 months after discharge. The questionnaires included questions about symptom knowledge, lifestyle behavior, and patients were asked to report on their diagnosis. Results: A total of 282 patients were included (mean age 71.8 years, 57.1% men). Self-reported symptom knowledge was increased at 3 months (P < .001), and this persisted at 12 months. There was a poor correlation (r = .082; P = .171) between increasing symptom knowledge and stated lifestyle behavior changes. In all, 63% of the respondents correctly identified their own cerebrovascular subtype. Thirty-seven percent had quit smoking after 12 months, 30% reported that they used less sugary items, and 26% used less fatty food after the cerebrovascular event. Conclusions: Stroke survivors reported increased stroke symptoms knowledge after 3 and 12 months. A proportion of patients made changes in lifestyle behavior. Only 2 out of 3 patients correctly identified their own cerebrovascular subtype, indicating room for improvement in clinical practice when informing and communicating with stroke and transient ischemic attack patients about their diagnosis.     

Trajectories and stability of self‐reported short sleep duration from adolescence to adulthood

The trajectories and stability of self‐reported sleep duration recorded at ages 13, 15, and 23 years on reported sleep duration at age 30 years among 1105 students (55% male) who participated in the Norwegian Longitudinal Health and Behaviour Study were examined. Questionnaire data were used to obtain demographic and sleep variables. Dichotomised short sleep duration was based on normative values and set as ≤8.5 h (age 13 years), ≤8 h (age 15 years) and ≤7 h (ages 23 and 30 years). Results indicated a significant overall reduction in total sleep duration (h per night) across age groups. Sleep duration (continuous) at age 15 and 23 years (whole group) was moderately but positively correlated with sleep duration at age 30 years (P < 0.01). When split by sex, at age 15 years, this association was present among females only (P < 0.01); however, at age 23 years, this association was present in both male and females (both P < 0.001). Categorical short sleep at age 23 years (whole group) was associated with short sleep at age 30 years (unadjusted odds ratio = 3.67, 95% confidence interval 2.36–5.69). Following sex stratification, this effect was significant for both males (unadjusted odds ratio = 3.77, 95% confidence interval: 2.22–6.42) and females (unadjusted odds ratio = 2.71, 95% confidence interval: 1.46–5.04). No associations were noted for categorical short sleep at ages 13 or 15 years, and subsequent short sleep at 30 years. Habitual short sleep duration during middle adulthood is not sustained from the time of early adolescence. Rather, these trends appear to be formed during early adulthood.