'I live in extremes': A qualitative investigation of Autistic adults' experiences of inertial rest and motion

LAY ABSTRACT

'Autistic inertia' is a term used by Autistic people to refer to difficulties with starting and stopping tasks. However, there has not been much research on Autistic inertia. The research that is available on Autistic inertia has mostly focused on the negative aspects of inertia, rather than on the possible benefits of needing to continue tasks. In this research, we wanted to understand more about Autistic people's experiences of inertia and to work out what things might influence these experiences. Autistic and non-Autistic researchers spoke in-depth to 24 Autistic adults. We identified four key ideas from people's responses. Autistic people spoke about their inertial 'difficulties moving from one state to another' and described how these challenges affected them 'every single day'. While they experienced inertia as 'the single most disabling part of being Autistic', people also described the positive aspects of inertia, including the joy they felt when completely immersed in a task. Our Autistic participants emphasised that inertial difficulties are experienced by everyone, the intensity of these task-switching difficulties might be especially challenging for Autistic people. Our findings also reveal how Autistic inertia can be seen both as a disabling and as an enabling condition.

Resting state functional connectivity provides mechanistic predictions of future changes in sedentary behavior

Sedentary behaviors are increasing at the cost of millions of dollars spent in health care and productivity losses due to physical inactivity-related deaths worldwide. Understanding the mechanistic predictors of sedentary behaviors will improve future intervention development and precision medicine approaches. It has been posited that humans have an innate attraction towards effort minimization and that inhibitory control is required to overcome this prepotent disposition. Consequently, we hypothesized that individual differences in the functional connectivity of brain regions implicated in inhibitory control and physical effort decision making at the beginning of an exercise intervention in older adults would predict the change in time spent sedentary over the course of that intervention. In 143 healthy, low-active older adults participating in a 6-month aerobic exercise intervention (with three conditions: walking, dance, stretching), we aimed to use baseline neuroimaging (resting state functional connectivity of two a priori defined seed regions), and baseline accelerometer measures of time spent sedentary to predict future pre-post changes in objectively measured time spent sedentary in daily life over the 6-month intervention. Our results demonstrated that functional connectivity between (1) the anterior cingulate cortex and the supplementary motor area and (2) the right anterior insula and the left temporoparietal/temporooccipital junction, predicted changes in time spent sedentary in the walking group. Functional connectivity of these brain regions did not predict changes in time spent sedentary in the dance nor stretch and tone conditions, but baseline time spent sedentary was predictive in these conditions. Our results add important knowledge toward understanding mechanistic associations underlying complex out-of-session sedentary behaviors within a walking intervention setting in older adults.

How to Interpret Resting-State fMRI: Ask Your Participants

Resting-state fMRI (rsfMRI) reveals brain dynamics in a task-unconstrained environment as subjects let their minds wander freely. Consequently, resting subjects navigate a rich space of cognitive and perceptual states (i.e., ongoing experience). How this ongoing experience shapes rsfMRI summary metrics (e.g., functional connectivity) is unknown, yet likely to contribute uniquely to within- and between-subject differences. Here we argue that understanding the role of ongoing experience in rsfMRI requires access to standardized, temporally resolved, scientifically validated first-person descriptions of those experiences. We suggest best practices for obtaining those descriptions via introspective methods appropriately adapted for use in fMRI research. We conclude with a set of guidelines for fusing these two data types to answer pressing questions about the etiology of rsfMRI.

Factors associated with work-related burnout in NHS staff during COVID-19: a cross-sectional mixed methods study

OBJECTIVES

To measure work-related burnout in all groups of health service staff during the COVID-19 pandemic and to identify factors associated with work-related burnout.

DESIGN

Cross-sectional staff survey.

SETTING

All staff grades and types across primary and secondary care in a single National Health Service organisation.

PARTICIPANTS

257 staff members completed the survey, 251 had a work-related burnout score and 239 records were used in the regression analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: (1) Work-related burnout as measured by the Copenhagen Burnout Inventory; (2) factors associated with work-related burnout identified through a multiple linear regression model; and (3) factors associated with work-related burnout identified through thematic analysis of free text responses.

RESULTS

After adjusting for other covariates (including age, sex, job, being able to take breaks and COVID-19 knowledge), we observed meaningful changes in work-related burnout associated with having different COVID-19 roles (p=0.03), differences in the ability to rest and recover during breaks (p<0.01) and having personal protective equipment concerns (p=0.04). Thematic analysis of the free text comments also linked burnout to changes in workload and responsibility and to a lack of control through redeployment and working patterns. Reduction in non-COVID-19 services has resulted in some members of staff feeling underutilised, with feelings of inequality in workload.

CONCLUSIONS

Our analyses support anecdotal reports of staff struggling with the additional pressures brought on by COVID-19. All three of the factors we found to be associated with work-related burnout are modifiable and hence their effects can be mitigated. When we next find ourselves in extraordinary times the ordinary considerations of rest and protection and monitoring of the impact of new roles will be more important than ever.

Brief Report: Can a Composite Heart Rate Variability Biomarker Shed New Insights About Autism Spectrum Disorder in School-Aged Children?

Several studies show altered heart rate variability (HRV) in autism spectrum disorder (ASD), but findings are neither universal nor specific to ASD. We apply a set of linear and nonlinear HRV measures-including phase rectified signal averaging-to segments of resting ECG data collected from school-age children with ASD, age-matched typically developing controls, and children with other psychiatric conditions characterized by altered HRV (conduct disorder, depression). We use machine learning to identify time, frequency, and geometric signal-analytical domains that are specific to ASD (receiver operating curve area = 0.89). This is the first study to differentiate children with ASD from other disorders characterized by altered HRV. Despite a small cohort and lack of external validation, results warrant larger prospective studies.

Oral contraceptive use, especially during puberty, alters resting state functional connectivity

Millions of women worldwide use oral contraceptives (OCs), often starting during puberty/adolescence. It is, however, unknown how OC use during this critical period of development affects the brain. The objective of the current study was to examine resting state functional connectivity (FC) in the default mode network (DMN), central executive network (CEN), salience network (SN), reward network (RN), and subcortical limbic network of the brain using independent component analysis (ICA) between pubertal- and adult-onset OC users (n = 27) and naturally cycling women (n = 48). It was hypothesized that OC use would result in network-specific increases and decreases in FC and that pubertal-onset OC use would result in differences to the aforementioned networks compared to adult-onset OC use. Pubertal-onset OC use is related to heightened FC in the SN compared to adult-onset OC users. In general, OC use also increases connectivity in the SN, CEN, RN, and subcortical limbic network compared to NC women. No significant differences in connectivity were observed in the DMN between OC users and NC women. These findings provide a mechanistic insight for the altered executive functioning and emotion/reward processing previously seen in OC users, which may then increase their vulnerability to mental health conditions.

Acute exposure of rats to a severe stressor alters the circadian pattern of corticosterone and sensitizes to a novel stressor: Relationship to pre-stress individual differences in resting corticosterone levels

Traumatic events have been proposed to be associated with hypo-activity of the hypothalamic-pituitary-adrenal (HPA) axis, but data in animal models exposed to severe stressors are controversial and have important methodological concerns. Individual differences in resting or stress levels of corticosterone might explain some of the inconsistencies. We then studied this issue in male rats exposed to 2 h immobilization on boards (IMO), a severe stressor. Thirty-six rats were blood sampled under resting conditions four times a day on three non-consecutive days. Then, they were assigned to control (n = 14) or IMO (n = 22) to study the HPA response to IMO, the stressor-induced alterations in the circadian pattern of corticosterone (CPCORT), and the behavioral and HPA responsiveness to an open-field. Individual differences in pre-IMO resting corticosterone were inconsistent, but averaging data markedly improved consistency. The CPCORT was markedly altered on day 1 post-IMO (higher trough and lower peak levels), less altered on day 3 and apparently normal on day 7. Importantly, when rats were classified in low and high resting corticosterone groups (LCORT and HCORT, respectively), on the basis of the area under the curve (AUC) of the averaged pre-IMO data, AUC differences between LCORT and HCORT groups were maintained in controls but disappeared in IMO rats during the post-IMO week. Open-field hypo-activity and corticosterone sensitization were similar in LCORT and HCORT groups nine days after IMO. A single IMO exposure causes long-lasting HPA alterations, some of them dependent on pre-stress resting corticosterone levels, with no evidence for post-IMO resting corticosterone hypo-activity.

Stronger resting-state neural oscillations associated with wiser advising from the 2nd- but not the 3rd-person perspective

This is the first electroencephalogram study exploring the personal perspective effect on wise advising. Participants advised hypothetical protagonists in life dilemmas from both the 2nd- and 3rd-person perspective. Their advice for each dilemma was rated by two independent raters on wisdom criteria, i.e., metacognitive humility, metacognitive flexibility, and perspective taking. The results revealed that participants felt a significantly shorter psychological distance from protagonists when advising from the 2nd- (vs. the 3rd-) person perspective, p < 0.001. However, there was no significant effect of perspective condition on the wisdom score. Nevertheless, stronger resting-state absolute EEG powers in the frontal lobe were associated with wiser advising from the 2nd-, but not the 3rd-person perspective. Moreover, Z tests revealed that the correlations between the resting-state absolute EEG powers and wisdom scores were significantly stronger during advising from the 2nd- than the 3rd-person perspective. These results suggest that advising from the 2nd-person perspective was more self-related, and mental activities during rest contributed to advising from the 2nd- but not the 3rd-person perspective.

Abnormal Regional Neural Activity and Reorganized Neural Network in Obesity: Evidence from Resting-State fMRI

OBJECTIVE

This study aimed to investigate regional neural activity and regulation of patterns in the reorganized neural network of obesity and explore the correlation between brain activities and eating behavior.

METHODS

A total of 23 individuals with obesity and 23 controls with normal weight were enrolled. Functional magnetic resonance imaging (fMRI) data were acquired using 3.0-T MRI. Amplitude of low-frequency fluctuation and functional connectivity (FC) analyses were conducted using Data Processing Assistant for resting-state fMRI and Resting-State fMRI Data Analysis Toolkit (REST).

RESULTS

The group with obesity showed increased amplitude of low-frequency values in left fusiform gyrus/amygdala, inferior temporal gyrus (ITG), hippocampus/parahippocampal gyrus, and bilateral caudate but decreased values in right superior temporal gyrus. The group with obesity showed increased FC between left caudate and right superior temporal gyrus, left fusiform gyrus/amygdala and left ITG, right caudate and left fusiform gyrus/amygdala, and right caudate and left hippocampus/parahippocampal gyrus. Dutch Eating Behavior Questionnaire-Emotional scores were positively correlated with FC between left hippocampus/parahippocampal gyrus and right caudate but negatively correlated with FC between left fusiform gyrus/amygdala and left ITG.

CONCLUSIONS

The study indicated the reorganized neural network presented as a bilateral cross-regulation pattern across hemispheres between reward and various appetite-related functional processing, thus affecting emotional and external eating behavior. These results could provide further evidence for neuropsychological underpinnings of food intake and their neuromodulatory therapeutic potential in obesity.

Dopaminergic hypo-activity and reduced theta-band power in autism spectrum disorder: A resting-state EEG study

BACKGROUND

Prior studies using a variety of methodologies have reported inconsistent dopamine (DA) findings in individuals with autism spectrum disorder (ASD), ranging from dopaminergic hypo- to hyper-activity. Theta-band power derived from scalp-recorded electroencephalography (EEG), which may be associated with dopamine levels in frontal cortex, has also been shown to be atypical in ASD. The present study examined spontaneous eye-blink rate (EBR), an indirect, non-invasive measure of central dopaminergic activity, and theta power in children with ASD to determine: 1) whether ASD may be associated with atypical DA levels, and 2) whether dopaminergic dysfunction may be associated with aberrant theta-band activation.

METHOD

Participants included thirty-two children with ASD and thirty-two age-, IQ-, and sex-matched typically developing (TD) children. Electroencephalography and eye-tracking data were acquired while participants completed an eyes-open resting-state session. Blinks were counted and EBR was determined by dividing blink frequency by session duration and theta power (4-7.5 Hz) was extracted from midline leads.

RESULTS

Eye-blink rate and theta-band activity were significantly reduced in children with ASD as compared to their TD peers. For all participants, greater midline theta power was associated with increased EBR (related to higher DA levels).

CONCLUSIONS

These results suggest that ASD may be associated with dopaminergic hypo-activity, and that this may contribute to atypical theta-band power. Lastly, EBR may be a useful tool to non-invasively index dopamine levels in ASD and could potentially have many clinical applications, including selecting treatment options and monitoring treatment response.

Effects of Rest-Break on Mental Fatigue Recovery Determined by a Novel Temporal Brain Network Analysis of Dynamic Functional Connectivity

Mental fatigue is growingly considered to be associated with functional brain dysconnectivity. Although conventional wisdom suggests that rest break is an effective countermeasure, the underlying neural mechanisms and how they modulate fatigue-related brain dysconnectivity is largely unknown. Here, we introduce an empirical method to examine the reorganization of dynamic functional connectivity (FC) in a two-session experiment where one session including a mid-task break (Rest) compared to a successive task design in the other session (No-rest). Temporal brain networks were estimated from 20 participants and the spatiotemporal architecture was examined using our newly developed temporal efficiency analysis framework. We showed that taking a mid-task break leads to a restorative effect towards the end of experiment instead of immediate post-rest behaviour benefits. More importantly, we revealed a potential neural basis of our behaviour observation: the reduced spatiotemporal global integrity of temporal brain network in No-rest session was significantly improved with the break opportunity in the last task block of Rest session. Overall, we provided novel evidence to support beneficial effect of rest breaks in both behaviour performance and brain function. Moreover, these findings extended prior static FC studies of mental fatigue and highlight that altered dynamic FC may underlie cognitive fatigue.

Resting-State Brain Connectivity Predicts Weight Loss and Cognitive Control of Eating Behavior After Vertical Sleeve Gastrectomy

OBJECTIVE

The effects of sleeve gastrectomy (SG) on functional connectivity (FC) and associations with weight loss and eating-related cognitive control were investigated.

METHODS

In a longitudinal study, 14 SG patients (13 female; 42.1 presurgery BMI) completed study visits 1 month pre surgery and 12 months post surgery. Patients completed the Dutch Eating Behavior Questionnaire and resting-state functional magnetic resonance imaging scanning to measure FC. Data were analyzed using a seed-to-voxel approach in the CONN Toolbox to investigate pre-/postsurgery changes (n = 12) and to conduct predictive analysis (n = 14).

RESULTS

Seed-to-voxel analysis revealed changes in magnitude (decreases) and directionality (positively correlated to anticorrelated) of FC pre to post surgery within and between default mode network, salience network, and frontoparietal network nodes [Family-Wise Error (FWE) corrected at P < 0.05]. Baseline FC of the nucleus accumbens (with insula) and hypothalamus (with precentral gyrus) predicted 12-month post-SG % total weight loss (FWE-P < 0.05). Baseline FC of the hippocampus, frontoparietal network, and default mode network nodes predicted improvement in cognitive control of eating behavior 12 months after SG (FWE-P < 0.05).

CONCLUSIONS

Our findings demonstrate changes in FC magnitude and directionality post versus pre surgery within and between resting-state networks and frontal, paralimbic, and visual areas in SG patients. Baseline FC predicted weight loss and changes in cognitive control of food intake behavior at 12 months. These could serve as predictive biomarkers for bariatric surgery.

Dynamic brain network configurations during rest and an attention task with frequent occurrence of mind wandering

Mind wandering (MW) has become a prominent topic of neuroscientific investigation due to the importance of understanding attentional processes in our day-to-day experiences. Emerging evidence suggests a critical role for three large-scale brain networks in MW: the default network (DN), the central executive network (CEN), and the salience network (SN). Advances in analytical methods for neuroimaging data (i.e., dynamic functional connectivity, DFC) demonstrate that the interactions between these networks are not static but dynamically fluctuate over time (Chang & Glover, 2010, NeuroImage, 50(1), 81-98). While the bulk of the evidence comes from studies involving resting-state functional MRI, a few studies have investigated DFC during a task. Direct comparison of DFC during rest and task with frequent MW is scarce. The present study applies the DFC method to neuroimaging data collected from 30 participants who completed a resting-state run followed by two runs of sustained attention to response task (SART) with embedded probes indicating a high prevalence of MW. The analysis identified five DFC states. Differences between rest and task were noted in the frequency of three DFC states. One DFC state characterized by negative DN-CEN/SN connectivity along with positive CEN-SN connectivity was more frequently observed during task vs. rest. Two DFC states, one of which was characterized by weaker connectivity between networks, were more frequently observed during rest than task. These findings suggest that the dynamic relationships between brain networks may vary as a function of whether ongoing cognitive activity unfolds in an "unconstrained" manner during rest or is "constrained" by task demands.

Work design for airport security officers: Effects of rest break schedules and adaptable automation

This study investigated whether there is empirical support for the current EU regulation mandating breaks of at least 10 min after each period of 20 min continuously reviewing X-ray images in airport security screening. As a second goal, it examined whether providing more autonomy to airport security officers (in the form of spontaneous rest breaks and adaptable automation) would improve their performance and subjective state. Seventy-two student participants had to indicate the presence (or absence) of a threat item (either a gun or a knife) in a series of grey-scaled X-ray images of cabin baggage. Three work-rest schedules were examined: spontaneous breaks (i.e. participants could take breaks at any time), two 5-min breaks and two 10-min breaks during a 1-h testing session. Furthermore, half of the participants were assisted in their task by an adaptable support system offering three levels of automation: (1) no support, (2) cues indicating the presence of a potential threat item, and (3) cues indicating the exact location of a potential threat item. Results showed no performance differences between break regimes, which suggests that there may be viable alternatives to the current EU regulations. It also emerged that providing participants with adaptable automation did not lead to better detection performance but resulted in a less positive response bias than participants without automatic support. Implications for current aviation security regulations are discussed.

Neurocircuitry associated with symptom dimensions at baseline and with change in borderline personality disorder

Borderline personality disorder (BPD) is a serious illness associated with chronic suffering and self-injurious behavior. Parsing the relationships between specific symptom domains and their underlying biological mechanisms may help us further understand the neural circuits implicated in these symptoms and how they might be amenable to change with treatment. This study examines the association between symptom dimensions (Affective Disturbance, Cognitive Disturbance, Disturbed Relationships, and Impulsivity) and amygdala resting-state functional connectivity (RSFC) in a sample of adults with BPD (n = 18). We also explored the relationships between change in symptom dimensions and change in amygdala RSFC in a subset of this sample (n = 13) following 8 weeks of quetiapine or placebo. At baseline, higher impulsivity was associated with increased positive RSFC between right amygdala and left hippocampus. There were no significant differences in neural change between treatment groups. Improvement in cognitive disturbance was associated with increased positive RSFC between left amygdala and temporal fusiform and parahippocampal gyri. Improvement in disturbed relationships was associated with increased negative RSFC between right amygdala and frontal pole. These results support that specific dimensions of BPD are associated with specific neural connectivity patterns at baseline and with change, which may represent neural treatment targets.

The local properties of bold signal fluctuations at rest monitor inhibitory control training in adolescents

Inhibitory control (IC) plays a critical role in cognitive and socio-emotional development. Short-term IC training improves IC abilities in children and adults. Surprisingly, few studies have investigated the IC training effect during adolescence, a developmental period characterized by high neuroplasticity and the protracted development of IC abilities. We investigated behavioural and functional brain changes induced by a 5-week computerized and adaptive IC training in adolescents. We focused on the IC training effects on the local properties of functional Magnetic Resonance Imaging (fMRI) signal fluctuations at rest (i.e., Regional Homogeneity [ReHo] and fractional Amplitude of Low Frequency Fluctuations [fALFF]). Sixty adolescents were randomly assigned to either an IC or an active control training group. In the pre- and post-training sessions, cognitive ('Cool') and emotional ('Hot') IC abilities were assessed using the Colour-Word and Emotional Stroop tasks. We found that ReHo and fALFF signals in IC areas (IFG, ACC, Striatum) were associated with IC efficiency at baseline. This association was different for Cool and Hot IC. Analyses also revealed that ReHo and fALFF signals were sensitive markers to detect and monitor changes after IC training, while behavioural data did not, suggesting that brain functional changes at rest precede behavioural changes following training.

Prior head injury but not sex or sports-participation affects expectations for post-injury rest and activity in simulated mild traumatic brain injury

Rest acutely followed by a gradual return to activity is commonly recommended for mild traumatic brain injury (TBI). However, the general public's rest and activity expectations for this injury are unknown, as are the individual factors that might affect them. 165 individuals completed an online survey. A series of between-groups comparisons of expectations for the week following a mild TBI was performed. The comparisons were between individuals with or without a prior mild TBI; sports-playing versus non-sports-playing individuals, and; females versus males. Expectations were elicited for 39 everyday behaviours referred to in mild TBI patient advice. Compared to a rating indicating 'no change' in the amount of pre-injury activity, "rest" was expected for 37 items (p's < .05). Expectations were not different based on participants' sex or sports-participation. However, for seven predominantly cognitive items such as studying, a prior injury increased rest expectations (p < .05; small-to-medium effects). The findings indicate that whilst the proposed activity restrictions are appropriate for some circumstances such as acutely postinjury, they have the potential to be overly strong. To address this potential, especially with first-ever injury, clinicians and sports officials should check their patient's postinjury rest and activity plans when providing active rest advice.

Resting-state functional connectivity in medication-naïve adolescents with major depressive disorder

Adolescence is a vulnerable period for major depressive disorder (MDD). The aim of our study was to investigate resting-state functional connectivity (RSFC) in first-episode, medication-naïve adolescent MDD patients. Twenty-three drug-naïve adolescents diagnosed with first-episode MDD and 27 healthy participants were enrolled. Seed-to-voxel RSFC analyses were performed. The frontolimbic circuit regions of interest included the amygdala, anterior cingulate cortex, insula, and hippocampus. A correlation analysis between the RSFC and Children's Depression Inventory, Hamilton depression rating scale, and duration of episodes was performed. The adolescents with MDD exhibited the following characteristics: a lower RSFC between the right amygdala and right superior frontal gyrus; a lower RSFC between the right hippocampus and clusters including the right insula and right middle frontal gyrus; a higher RSFC between the left insula and clusters including the bilateral middle frontal gyrus, right superior frontal gyrus, and right frontal pole; and a higher RSFC between the left dorsal anterior cingulate cortex and a cluster including the left insula. Medication-naïve adolescents with depression display lower connectivity of several brain regions implicated in processing, regulation, and memory of emotions. Higher connectivity was observed in brain regions that potentially explain rumination, impaired concentration, and physiological arousal.

Repetitive verbal behaviors are not always harmful signs: Compensatory plasticity within the language network in aphasia

Repetitive verbal behaviors such as conduite d'approche (CdA) and mitigated echolalia (ME) are well-known phenomena since early descriptions of aphasia. Nevertheless, there is no substantial fresh knowledge on their clinical features, neural correlates and treatment interventions. In the present study we take advantage of three index cases of chronic fluent aphasia showing CdA, ME or both symptoms to dissect their clinical and neural signatures. Using multimodal neuroimaging (structural magnetic resonance imaging and [18]-fluorodeoxyglucose positron emission tomography during resting state), we found that despite of the heterogeneous lesions in terms of etiology (stroke, traumatic brain injury), volume and location, CdA was present when the lesion affected in greater extent the left dorsal language pathway, while ME resulted from preferential damage to the left ventral stream. The coexistence of CdA and ME was associated with involvement of areas overlapping with the structural lesions and metabolic derangements described in the subjects who showed one of these symptoms (CdA or ME). These findings suggest that CdA and ME represent the clinical expression of plastic changes that occur within the spared language network and its interconnected areas in order to compensate for the linguistic functions that previously relied on the activity of the damaged pathway. We discuss the results in the light of this idea and consider alternative undamaged neural networks that may support CdA and ME.

Resting-state anticorrelated networks in Schizophrenia

Converging evidences from different lines of research suggest abnormalities in functional brain connectivity in schizophrenia. While positively correlated brain networks have been well researched, anticorrelated functional connectivity remains under explored. Hence, in this study we examined (1) the resting-state anticorrelated networks in schizophrenia, and (2) the accuracy of support vector machines (SVMs) in differentiating healthy individuals from schizophrenia patients using these anticorrelated networks. The sample consisted of 56 patients with DSM-IV schizophrenia and 56 healthy controls. We computed functional connectivity matrices and used Anticorrelation after Mean of Antilog method (AMA) to select predominantly anticorrelated networks. The basal ganglia, thalamus, lingual gyrus, and cerebellar vermis showed significantly different, Type A (decreased anticorrelation) connections. The medial temporal lobe and posterior cingulate gyri showed significantly different, Type B (increased anticorrelation) connections. Use of SVM on AMA networks showed moderate accuracy in differentiating schizophrenia and healthy controls. Our results suggest that anticorrelated networks between the sub-cortical and cortical areas are abnormal in schizophrenia and this has potential to be a differential biomarker. These preliminary findings, if replicated in future studies with larger number of patients, and advanced machine learning techniques could have potential clinical applications.

Wakeful resting and memory retention: a study with healthy older and younger adults

Studies indicate that a brief period of wakeful rest after learning supports memory retention, whereas distraction weakens it. It is open for investigation whether advanced age has a significant effect on the impact of post-learning wakeful rest on memory retention for verbal information when compared to a cognitively demanding distraction task. In this study, we examined (1) whether post-learning rest promotes verbal memory retention in younger and older adults and (2) whether the magnitude of the rest benefit changes with increasing age. Younger adults and older adults learned and immediately recalled two consecutive word lists. After one word list, participants rested wakefully for 8 min; after the other list, they solved matrices. Memory performance was again tested in a surprise free recall test at the end of the experimental session. We found that, overall, younger adults outperformed older adults. Also, memory retention was higher following a wakeful rest phase compared to distraction. A detailed analysis revealed that this wakeful rest benefit was significant for the older adults group, whereas the younger adults group retained a similar amount of information in both post-encoding conditions. We assume that older adults can profit more from a wakeful rest phase after learning and are more prone to distraction than younger adults. With increasing age, a short break immediately after information uptake may help better retain the previously learned information, while distraction after learning tends to weaken memory retention.

Developmental changes in resting-state functional networks among individuals with and without internalizing psychopathologies

BACKGROUND

Three well-established intrinsic connectivity networks (ICNs) involved in cognitive-affective processing include the cognitive control network (CCN), default mode network (DMN), and salience and emotional network (SEN). Despite recent advances in understanding developmental changes in these ICNs, the majority of research has focused on single seeds or networks in isolation with limited age ranges. Additionally, although internalizing psychopathologies (IPs), such as anxiety and depression, are often characterized by maladaptive cognitive-affective processing styles, it is not clear how IP history influences age-related changes in brain networks.

METHOD

The current study aimed to characterize the normative development of the CCN, DMN, and SEN across a large age-span (7-29 year olds) of typically developing (TD) individuals (n = 97). We also explore how age may impact differences in network connectivity between TD individuals and patients with IPs (n = 136).

RESULTS

Among TD individuals, DMN and CCN connectivity strengthened with age, whereas connectivity between the SEN and ventromedial prefrontal cortex weakened across development. When exploring group (IP vs. TD) differences, the IP group was characterized by greater connectivity between the CCN and cerebellum and between the SEN and caudate from childhood to early adulthood, relative to TD individuals. In addition, patients with IPs, versus TD individuals, exhibited reduced connectivity between the SEN and medial frontal gyrus from adolescence to adulthood.

CONCLUSIONS

The current findings shed light on differential age-related changes in brain network patterns among psychiatrically free, TD individuals and those with internalizing disorders, and may provide plausible targets for novel mechanism-based treatments that differ based on developmental stage.

The effects of habituation and adding a rest-frame on experienced simulator sickness in an advanced mobility scooter driving simulator

The aim of this article is to investigate the effect of a physical rest-frame, habituation and age on simulator sickness in an advanced mobility scooter driving simulator. Twenty-six young and 34 older adults completed a total of 12 drives in an advanced mobility scooter driving simulator over two visits. A 2x2 crossover design was used to measure the effect of a rest frame that was added to the driving simulator on either the first or second visit. The Simulator Sickness Questionnaire was used to measure simulator sickness symptoms. A significant decrease in simulator sickness was observed between the first and the second visit. Older adults reported more severe simulator sickness symptoms compared to younger participants. No effect of rest-frame could be found. Habituation appears to be the most effective method to reduce simulator sickness in an advanced mobility scooter driving simulator. More research is needed to investigate simulator sickness in patient groups. Practitioner summary: Experiencing simulator sickness is a major problem across all types of simulators. The present experiment investigated the effect of a rest-frame, habituation and age on developing simulator sickness symptoms in an advanced mobility scooter driving simulator. Habituation appeared to be the most effective method to reduce simulator sickness.

Does development moderate the effect of early life assaultive violence on resting-state networks? An exploratory study

Current neurocircuitry models of PTSD do not account for developmental effects, despite that early life assaultive violence is a potent risk factor for PTSD. Here, we preliminarily evaluated developmental stage as a moderator of the effect of early life assaultive violence on resting-state connectivity amongst regions associated with emotion generation and regulation using fMRI. Participants were adult women (n = 25) and adolescent girls (n = 36) who had or had not experienced early life assaultive violence. We found significant interactions between developmental stage and trauma exposure on resting-state functional connectivity (FC). Left amygdala connectivity with the left ventral anterior cingulate gyrus (BA 32) was reduced among trauma-exposed compared to control adolescents, but increased among trauma-exposed compared to control adults. A corresponding pattern of results was identified for FC between rostral anterior cingulate gyrus seed region and a similar right ventral anterior superior frontal gyrus cluster. Increased FC in both regions for assaulted adult women scaled positively with self-reported emotion regulation difficulties. Our results should be viewed tentatively due to sample limitations, but provide impetus to examine whether neurocircuitry models of PTSD may be strengthened by accounting for developmental stage.

Neural activity related to volitional regulation of cortical excitability

To date there exists no reliable method to non-invasively upregulate or downregulate the state of the resting human motor system over a large dynamic range. Here we show that an operant conditioning paradigm which provides neurofeedback of the size of motor evoked potentials (MEPs) in response to transcranial magnetic stimulation (TMS), enables participants to self-modulate their own brain state. Following training, participants were able to robustly increase (by 83.8%) and decrease (by 30.6%) their MEP amplitudes. This volitional up-versus down-regulation of corticomotor excitability caused an increase of late-cortical disinhibition (LCD), a TMS derived read-out of presynaptic GABAB disinhibition, which was accompanied by an increase of gamma and a decrease of alpha oscillations in the trained hemisphere. This approach paves the way for future investigations into how altered brain state influences motor neurophysiology and recovery of function in a neurorehabilitation context.

Altered intrinsic local activity and cognitive dysfunction in HIV patients: A resting-state fMRI study

Purpose

To characterize resting-state brain activation patterns and investigate altered areas for cognitive decline in HIV patients.

Methods

Twelve male HIV patients with intact cognition (HIV-IC), 10 with HIV-associated neurocognitive disorder (HAND), and 11 male healthy controls (HC) underwent resting-state functional MRI (rsfMRI). Three rsfMRI values, regional homogeneity (ReHo), amplitude of low-frequency fluctuation (ALFF), and fractional ALFF (fALFF) were calculated and compared between groups. Correlation analyses were performed between rsfMRI values and neuropsychological tests.

Results

rsfMRI analyses revealed decreased rsfMRI values in the frontal areas, and increases in the posterior brain regions for both HIV-IC and HAND compared to HC. When directly compared to HIV-IC, HAND showed lower fALFF in the orbitofrontal cortex and higher ReHo in the primary sensorimotor area. Additionally, decreased orbitofrontal fALFF, increased sensorimotor ReHo, and a larger difference between the two values were highly correlated with decreased verbal memory and executive function in HIV patients.

Conclusions

Regardless of cognitive status, altered local intrinsic activities were found in HIV patients. The orbitofrontal cortex and primary sensorimotor area were more disrupted in HAND relative to HIV-IC and correlated with behavioral performance, suggesting these areas are relevant to cognitive impairment in HIV patients.

The impact of work rest scheduling for prolonged standing activity

Prolonged standing can cause discomfort on the body of the workers and can lead to injury and occupational disease. One of the ergonomic intervention is through improving the work-rest scheduling. The purpose of this study are to identify the fatigue level from the perception of the worker and to investigate the impact of the work-rest scheduling to the standing workers for 12 h working time with a different gender. This study involved two methods which are self-assessment of the worker and direct measurement by using electromyography (EMG). For self-assessment, 80 workers have been interviewed using questionnaire in order to identify the fatigue level. For direct measurement, EMG was attached to the 15 selected workers at their respective leg and lower back to analyse the muscle efforts. In terms of perception, the results show the discomfort and fatigue level at the lower body region in the following order as foot ankle, lower back and leg. There is a significant difference between gender on discomfort pain for foot ankle and leg. The results show short frequent break by 10 min can reduce the fatigue at the leg and infrequent long break is preferable in order to reduce the fatigue at the lower back. In conclusion, it was found that prolonged standing affect the muscle fatigue and discomfort especially lower extremities such as foot ankle, lower back and leg. Besides that, different type of work rest scheduling and gender have significant result towards the muscle fatigue development.

A pilot study of GABAB correlates with resting-state functional connectivity in five depressed female adolescents

Connectivity features based on resting-state (RS) functional magnetic resonance imaging (fMRI) demonstrate great promise as biomarkers to guide diagnosis and treatment in major depressive disorder (MDD). However, there is a pressing need for valid, reliable biomarkers closer to the bedside for clinical research and practice. This study directly compared RS-fMRI connectivity features with transcranial magnetic stimulation (TMS) neurophysiological measures, long interval cortical inhibition (LICI) and cortical silent period (CSP), in female adolescents with MDD. LICI-200 showed the most significant associations with RS functional connectivity features, demonstrating its potential to evaluate the neurochemical underpinnings of network features in MDD.

Myosin Head Configurations in Resting and Contracting Murine Skeletal Muscle

Transgenic mouse models have been important tools for studying the relationship of genotype to phenotype for human diseases, including those of skeletal muscle. We show that mouse skeletal muscle can produce high quality X-ray diffraction patterns establishing the mouse intact skeletal muscle X-ray preparation as a potentially powerful tool to test structural hypotheses in health and disease. A notable feature of the mouse model system is the presence of residual myosin layer line intensities in contracting mouse muscle patterns. This provides an additional tool, along with the I1,1/I1,0 intensity ratio, for estimating the proportions of active versus relaxed myosin heads under a given set of conditions that can be used to characterize a given physiological condition or mutant muscle type. We also show that analysis of the myosin layer line intensity distribution, including derivation of the myosin head radius, Rm, may be used to study the role of the super-relaxed state in myosin regulation. When the myosin inhibitor blebbistatin is used to inhibit force production, there is a shift towards a highly quasi-helically ordered configuration that is distinct from the normal resting state, indicating there are more than one helically ordered configuration for resting crossbridges.

The impact of sedentarism on heart rate variability (HRV) at rest and in response to mental stress in young women

Sedentarism is one of the main risk factors for the onset of cardiometabolic diseases. Some biomarkers, such as heart rate variability (HRV), have been largely studied and found to be involved in the genesis of the dysfunctions associated with sedentary behavior. However, comparatively few studies have focused on the female sex. The objective of this study was to analyze the hemodynamic, autonomic and quality of life parameters at rest and in response to mental stress of sedentary and physically active young women. A total of 96 women, 18-30 years of age, were divided into sedentary (SW = 48) and active (AW = 48) groups. Anthropometric, hemodynamic and quality of life parameters were evaluated and the R-R interval was recorded to quantify the cardiac autonomic modulation at rest and in response to the Stroop Color Test. The groups were similar in age, weight, height, body mass index, fat percentage, systolic and diastolic blood pressure values and glycemia. The physical health domain of quality of life was compromised in the SW group. The SW group presented higher heart rate, lower variance of RR interval and RMSSD and higher cardiac sympathovagal balance (LF/HF) both at rest and in response to the mental stress test. We concluded that sedentary lifestyle in women induces impairment in autonomic cardiac modulation at rest and in response to physiological stress, compromising the quality of life, even before altering any cardiovascular or metabolic clinical parameters, reinforcing the potential role of HRV as early marker of cardiovascular risk in this population.

Action plan interrupted: resolution of proactive interference while coordinating execution of multiple action plans during sleep deprivation

The ability to retain an action plan to execute another is necessary for most complex, goal-directed behavior. Research shows that executing an action plan to an interrupting event can be delayed when it partly overlaps (vs. does not overlap) with the retained action plan. This phenomenon is known as partial repetition costs (PRCs). PRCs reflect proactive interference, which may be resolved by inhibitory, executive control processes. We investigated whether these inhibitory processes are compromised due to one night of sleep deprivation. Participants were randomized to a sleep-deprived group or a well-rested control group. All participants performed an action planning task at baseline after a full night of sleep, and again either after a night of sleep deprivation (sleep-deprived group) or a full night of sleep (control group). In this task, two visual events occurred in a sequence. Participants retained an action plan to the first event in working memory while executing a speeded action to the second (interrupting) event; afterwards, they executed the action to the first event. The two action plans either partly overlapped (required the same hand) or did not (required different hands). Results showed slower responses to the interrupting event during sleep deprivation compared to baseline and the control group. However, the magnitude of the PRCs was no different during sleep deprivation compared to baseline and the control group. Thus, one night of sleep deprivation slowed global responses to the interruption, but inhibitory processes involved in reducing proactive interference while responding to an interrupting event were not compromised. These findings are consistent with other studies that show sleep deprivation degrades global task performance, but does not necessarily degrade performance on isolated, executive control components of cognition. The possibility that our findings involve local as opposed to central inhibition is also discussed.

Endocrine regulation of migratory departure from stopover: Evidence from a longitudinal migratory restlessness study on northern wheatears

Most migrating birds make stopovers to replenish fuel stores. The decision to resume migration from stopover to a large extent shapes the temporal organization of migration. This decision is known to be shaped by a suite of intrinsic and extrinsic factors such as the bird's fuel stores and current weather conditions. However, how departures from stopover are physiologically regulated is largely unknown. We here present data that strongly indicate that corticosterone, a hormone with a stimulatory effect on locomotion, acts as a mediator between fuel stores and departure from stopover. In migrating northern wheatears (Oenanthe oenanthe) temporarily caged at stopover, we observed a positive relationship between the change in fuel stores and the concurrent change in glucocorticoid metabolite (GCM) levels measured in the birds' droppings. We also found a positive relationship between the change in GCM levels and the change in the intensity of nocturnal migratory restlessness. As in northern wheatears nocturnal migratory restlessness is an accurate proxy for stopover departure likelihood, our results indicate that corticosterone mediates between fuel stores and the decision to resume migration. Our unique longitudinal study represents a considerable advance in our understanding of the endocrine regulation of avian migration.

Impact of previous episodes of hepatic encephalopathy on short-term brain function recovery after liver transplantation: a functional connectivity strength study

Neuropsychological studies have documented an incomplete reversal of pre-existing cognitive dysfunction in cirrhotic patients after liver transplantation (LT) and have found this is more severe in patients with hepatic encephalopathy (HE). In this study, we aimed to investigate the impact of prior HE episodes on post-transplantation brain function recovery. Resting-state functional magnetic resonance imaging data was collected from 30 healthy controls and 33 cirrhotic patients (HE, n = 15 and noHE, n = 18) before and one month after LT. Long- and short-range functional connectivity strength (FCS) analysis indicated that before transplantation both noHE and HE groups showed diffuse FCS abnormalities relative to healthy controls. For the noHE group, the abnormal FCS found before LT largely returned to normal levels after LT, except for in the cerebellum, precuneus, and orbital middle frontal gyrus. However, the abnormal FCS prior to LT was largely preserved in the HE group, including high-level cognition-related (frontal and parietal lobes) and vision-related areas (occipital lobe, cuneus, and precuneus). In addition, comparisons between HE and noHE groups revealed that weaker FCS in default mode network (DMN) in HE group persisted from pre- to post- LT. Correlation analysis showed that changes in FCS in the left postcentral and right middle frontal gyrus correlated with alterations in neuropsychological performance and ammonia levels. In conclusion, the findings in this study demonstrate potential adverse effects of pre-LT episode of HE on post-LT brain function recovery, and reveal that DMN may be the most affected brain region by HE episodes, which can't be reversed by LT.

Functional work breaks in a high-demanding work environment: an experimental field study

Work breaks are known to have positive effects on employees' health, performance and safety. Using a sample of twelve employees working in a stressful and cognitively demanding working environment, this experimental field study examined how different types of work breaks (boxing, deep relaxation and usual breaks) affect participants' mood, cognitive performance and neurophysiological state compared to a control condition without any break. In a repeated measures experimental design, cognitive performance was assessed using an auditory oddball test and a Movement Detection Test. Brain cortical activity was recorded using electroencephalography. Individual's mood was analysed using a profile of mood state. Although neurophysiological data showed improved relaxation of cortical state after boxing (vs. 'no break' and 'deep relaxation'), neither performance nor mood assessment showed similar results. It remains questionable whether there is a universal work break type that has beneficial effects for all individuals. Practitioner Summary: Research on work breaks and their positive effects on employees' health and performance often disregards break activities. This experimental field study in a stressful working environment investigated the effect of different work break activities. A universal work break type that is beneficial for this workplace could not be identified.

Resting state functional connectivity in primary insomnia, generalized anxiety disorder and controls

Sleep abnormalities are extremely common in anxiety disorders and may contribute to their development and persistence. Their shared pathophysiological mechanisms could thus serve as biomarkers or targets for novel therapeutics. Individuals with Primary Insomnia were age- and sex-matched to controls and to persons with Generalized Anxiety Disorder. All underwent fMRI resting-state scans at 3-T. In Primary Insomnia and controls, sleep was recorded for 2 weeks using diaries and actigraphy. All participants completed state-anxiety and neuroticism inventories. Whole-brain connectivity of 6 fear- and extinction-related seeds were compared between the 3 groups using ANOVA. The only significant between-group main effect was seen for connectivity between the left amygdala seed and a bilateral cluster in the rostral anterior cingulate cortex. The latter is believed to exert top-down control over amygdala activity and their interaction may thus constitute an emotion regulatory circuit. This connectivity was significantly greatest in controls while Primary Insomnia was intermediate between that of controls and Generalized Anxiety Disorder. Across Primary Insomnia and control subjects, mean connectivity decreased with poorer sleep. Across all 3 groups, connectivity decreased with greater neuroticism and pre-scan anxiety. Decreased top-down control of the amygdala may increase risk of developing an anxiety disorder with preexisting Primary Insomnia.

Neural complexity as a potential translational biomarker for psychosis

BACKGROUND

The adaptability of the human brain to the constantly changing environment is reduced in patients with psychotic disorders, leading to impaired cognitive functions. Brain signal complexity, which may reflect adaptability, can be readily quantified via resting-state functional magnetic resonance imaging (fMRI) signals. We hypothesized that resting-state brain signal complexity is altered in psychotic disorders, and is correlated with cognitive impairment.

METHODS

We assessed 156 healthy controls (HC) and 330 probands, including 125 patients with psychotic bipolar disorder (BP), 107 patients with schizophrenia (SZ), 98 patients with schizoaffective disorder (SAD) and 230 of their unaffected first-degree relatives (76 BPR, 79 SADR, and 75 SZR) from four sites of the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) consortium. Using multi-scale entropy analysis, we determined whether patients and/or relatives had pathologic differences in complexity of resting-state fMRI signals toward regularity (reduced entropy in all time scales), or toward uncorrelated randomness (increased entropy in fine time scales that decays as the time scale increases) and how these complexity differences might be associated with cognitive impairment.

RESULTS

Compared to HC subjects, proband groups showed either decreased complexity toward regularity or toward randomness. SZ probands showed decreased complexity toward regular signal in hypothalamus, and BP probands in left inferior occipital, right precentral and left superior parietal regions, whereas no brain region with decreased complexity toward regularity was found in SAD probands. All proband groups showed significantly increased brain signal randomness in dorsal and ventral prefrontal cortex (PFC), and unaffected relatives showed no complexity differences in PFC regions. SZ had the largest area of involvement in both dorsal and ventral PFC. BP and SAD probands shared increased brain signal randomness in ventral medial PFC, BP and SZ probands shared increased brain signal randomness in ventral lateral PFC, whereas SAD and SZ probands shared increased brain signal randomness in dorsal medial PFC. Only SZ showed increased brain signal randomness in dorsal lateral PFC. The increased brain signal randomness in dorsal or ventral PFC was weakly associated with reduced cognitive performance in psychotic probands.

CONCLUSION

These observations support the loss of brain complexity hypothesis in psychotic probands. Furthermore, we found significant differences as well as overlaps of pathologic brain signal complexity between psychotic probands by DSM diagnoses, thus suggesting a biological approach to categorizing psychosis based on functional neuroimaging data.

The impact of intraoperative microbreaks with exercises on surgeons: A multi-center cohort study

Recent literature has demonstrated ergonomic risk to surgeons in the operating room. One method used in other industries to mitigate these ergonomic risks is the incorporation of microbreaks. Thus, intraoperative microbreaks with exercises in a non-crossover design were studied. Fifty-six attending surgeons from 4 Medical Centers volunteered first in a day of their regular surgeries and then second day where there were microbreaks with exercises that could be performed in the sterile field, answering questions after each case, without significantly increasing the duration of their surgeries. Surgeons self-reported improvement or no change in their mental focus (88%) and physical performance (100%) for the surgical day incorporating microbreaks with exercises. Discomfort in the shoulders was significantly reduced while distractions and flow impact was minimal. Eighty-seven percent of the surgeons wanted to incorporate the microbreaks with exercises into their OR routine. Intraoperative microbreaks with exercises may be a way to mitigate work-related musculoskeletal fatigue, pain and injury.

Psychological Impact of Cognitive Rest Following Sport-Related Concussion on Low Socioeconomic Status Adolescent Patients

PURPOSE

Describe the psychological impact of cognitive rest in adolescents recovering from concussion from sport-related concussion.

METHODS

Eight male football players with a previous sport concussion and full recovery completed semi-structured interviews during focus group sessions. Using content analysis, the researchers independently analyzed notes and transcriptions to identify themes associated with the psychological impact of cognitive rest.

RESULTS

Common themes included: 1) sport as social support, and 2) boredom-complicated recovery following cognitive rest.

CONCLUSIONS

The current treatment protocol indicating cognitive rest and removal from school and sport may be detrimental in a population that is peer-dependent. Future research should explore generalizability and additional factors that may complicate psychological recovery of adolescent athletes following concussive injuries.

[Correlation of Resting State Functional Connectivity with Behavioral and Psychological Indices]

In recent years, a large amount of data was published about resting state networks (RSN), namely, continu- ously recorded brain activity in a state of quiet wakefulness. In particular, such states are reflected in the spa- tial maps of active regions of the brain, obtained by means of functional magnetic resonance imaging (fMRI). RSNs have stable and reproducible spatial structure over time in healthy subjects, but may differ substantially in clinical pathology. One of the important parameters of the brain activity is functional connectivity (FC) of individual elements within a network or between resting state networks. This review considers results of the studies focused at correlation of behavioral indicators and FC of brain areas activated during resting state. In addition, we describe data on reproducibility of RSN over time in healthy subjects, as well as data on changes in FC-of networks, depending on the individual experience.

Postpartum Practices and Depression Prevalences: Technocentric and Ethnokinship Cultural Perspectives

Reports of non-Western prevalence of postpartum depression (PPD) are highly variable. This variation may indicate that the label of PPD may be unacceptable in some groups or not used, that manifestations may vary by culture, or that cross-cultural diagnostic standards do not match Western clinical criteria. These factors complicate efforts to explore the relationship of postpartum traditional practices to PPD between Western and non-Western cultures. Although Stern and Kruckman viewed PPD as a culture-bound phenomenon of Western culture, an expanding international literature has demonstrated that PPD occurs in a variety of countries. To address these issues, the authors examined the literature to describe cultural postpartum traditions, to explore possible relationships among practices and PPD prevalence, to critique the culture-bound theory, and to discuss clinical practice implications.

Resting-state qEEG predicts rate of second language learning in adults

Understanding the neurobiological basis of individual differences in second language acquisition (SLA) is important for research on bilingualism, learning, and neural plasticity. The current study used quantitative electroencephalography (qEEG) to predict SLA in college-aged individuals. Baseline, eyes-closed resting-state qEEG was used to predict language learning rate during eight weeks of French exposure using an immersive, virtual scenario software. Individual qEEG indices predicted up to 60% of the variability in SLA, whereas behavioral indices of fluid intelligence, executive functioning, and working-memory capacity were not correlated with learning rate. Specifically, power in beta and low-gamma frequency ranges over right temporoparietal regions were strongly positively correlated with SLA. These results highlight the utility of resting-state EEG for studying the neurobiological basis of SLA in a relatively construct-free, paradigm-independent manner.

Number of Players and Relative Pitch Area per Player: Comparing Their Influence on Heart Rate and Physical Demands in Under-12 and Under-13 Football Players

The aim of the present study is to analyse the influence of different large-sided games (LSGs) on the physical and physiological variables in under-12s (U12) and -13s (U13) soccer players. The effects of the combination of different number of players per team, 7, 9, and 11 (P7, P9, and P11, respectively) with three relative pitch areas, 100, 200, and 300 m² (A100, A200, and A300, respectively), were analysed in this study. The variables analysed were: 1) global indicator such as total distance (TD); work:rest ratio (W:R); player-load (PL) and maximal speed (V_max); 2) heart rate (HR) mean and time spent in different intensity zones of HR (<75%, 75–84%, 84–90% and >90%), and; 3) five absolute (<8, 8–13, 13–16 and >16 Km h^-1) and three relative speed categories (<40%, 40–60% and >60% V_max). The results support the theory that a change in format (player number and pitch dimensions) affects no similarly in the two players categories. Although it can seem that U13 players are more demanded in this kind of LSG, when the work load is assessed from a relative point of view, great pitch dimensions and/or high number of player per team are involved in the training task to the U12 players. The results of this study could alert to the coaches to avoid some types of LSGs for the U12 players such as: P11 played in A100, A200 or A300, P9 played in A200 or A300 and P7 played in A300 due to that U13>U12 in several physical and physiological variables (W:R, time spent in 84–90%HR_max, distance in 8–13 and 13–16 Km h^-1 and time spent in 40–60%V_max). These results may help youth soccer coaches to plan the progressive introduction of LSGs so that task demands are adapted to the physiological and physical development of participants.

Job demands and resting and napping opportunities for nurses during night shifts: impact on sleepiness and self-evaluated quality of healthcare

The aim of this field study is to describe night shift resting and napping strategies and to examine their beneficial effects on sleepiness and quality of work. The study was carried out with 16 nurses working in an intensive care unit. Data collected during 20 night shifts were related to job demands (systematic observations), to the duration and timing of rests and naps taken by nurses (systematic observations, sleep diaries), to sleepiness (Karolinska Sleepiness Scale), and to quality of work scores (visual analog scale). The results showed that the number of rests and naps depended on the job demands. Resting and napping lowered the levels of sleepiness at the end of the shift. There was no direct relationship between sleepiness and the quality of work score. Discussions about the choice of indicators for the quality of work are necessary. Suggestions for implementing regulations for prescribed napping during night shifts are presented.

Resting-state functional connectivity and nicotine addiction: prospects for biomarker development

Given conceptual frameworks of addiction as a disease of intercommunicating brain networks, examinations of network interactions may provide a holistic characterization of addiction-related dysfunction. One such methodological approach is the examination of resting-state functional connectivity, which quantifies correlations in low-frequency fluctuations of the blood oxygen level-dependent magnetic resonance imaging signal between disparate brain regions in the absence of task performance. Here, evidence of differentiated effects of chronic nicotine exposure, which reduces the efficiency of network communication across the brain, and acute nicotine exposure, which increases connectivity within specific limbic circuits, is discussed. Several large-scale resting networks, including the salience, default, and executive control networks, have also been implicated in nicotine addiction. The dynamics of connectivity changes among and between these large-scale networks during nicotine withdrawal and satiety provide a heuristic framework with which to characterize the neurobiological mechanism of addiction. The ability to simultaneously quantify effects of both chronic (trait) and acute (state) nicotine exposure provides a platform to develop a neuroimaging-based addiction biomarker. While such development remains in its early stages, evidence of coherent modulations in resting-state functional connectivity at various stages of nicotine addiction suggests potential network interactions on which to focus future addiction biomarker development.

Proneness to social anxiety modulates neural complexity in the absence of exposure: A resting state fMRI study using Hurst exponent

To test the hypothesis that brain activity is modulated by trait social anxiety, we measured the Hurst Exponent (HE), an index of complexity in time series, in healthy individuals at rest in the absence of any social trigger. Functional magnetic resonance imaging (fMRI) time series were recorded in 36 subjects at rest. All volunteers were healthy without any psychiatric, medical or neurological disorder. Subjects completed the Liebowitz Social Anxiety Scale (LSAS) and the Brief Fear of Negative Evaluation (BFNE) to assess social anxiety and thoughts in social contexts. We also obtained the fractional Amplitude of Low Frequency Fluctuations (fALFF) of the BOLD signal as an independent control measure for HE data. BFNE scores correlated positively with HE in the posterior cingulate/precuneus, while LSAS scores correlated positively with HE in the precuneus, in the inferior parietal sulci and in the parahippocamus. Results from fALFF were highly consistent with those obtained using LSAS and BFNE to predict HE. Overall our data indicate that spontaneous brain activity is influenced by the degree of social anxiety, on a continuum and in the absence of social stimuli. These findings suggest that social anxiety is a trait characteristic that shapes brain activity and predisposes to different reactions in social contexts.

Boosting long-term memory via wakeful rest: intentional rehearsal is not necessary, consolidation is sufficient

People perform better on tests of delayed free recall if learning is followed immediately by a short wakeful rest than by a short period of sensory stimulation. Animal and human work suggests that wakeful resting provides optimal conditions for the consolidation of recently acquired memories. However, an alternative account cannot be ruled out, namely that wakeful resting provides optimal conditions for intentional rehearsal of recently acquired memories, thus driving superior memory. Here we utilised non-recallable words to examine whether wakeful rest boosts long-term memory, even when new memories could not be rehearsed intentionally during the wakeful rest delay. The probing of non-recallable words requires a recognition paradigm. Therefore, we first established, via Experiment 1, that the rest-induced boost in memory observed via free recall can be replicated in a recognition paradigm, using concrete nouns. In Experiment 2, participants heard 30 non-recallable non-words, presented as ‘foreign names in a bridge club abroad’ and then either rested wakefully or played a visual spot-the-difference game for 10 minutes. Retention was probed via recognition at two time points, 15 minutes and 7 days after presentation. As in Experiment 1, wakeful rest boosted recognition significantly, and this boost was maintained for at least 7 days. Our results indicate that the enhancement of memory via wakeful rest is not dependent upon intentional rehearsal of learned material during the rest period. We thus conclude that consolidation is sufficient for this rest-induced memory boost to emerge. We propose that wakeful resting allows for superior memory consolidation, resulting in stronger and/or more veridical representations of experienced events which can be detected via tests of free recall and recognition.

[The influence of movement's observation on recuperation after physical fatigue]

The study aim was to investigate effects of mental activity, accompanied by mu-rhythm depression, on recuperation after physical fatigue. In a study participants performed 11 one minute bouts of static hand grip intermitted by 2 minutes restpauses. During pauses participants watched video with either dynamic hand grips (biological movements) or deformation of geometric figure (control). Obtained data showed there was a significant depression of mu-rhythm during biological movement's observation. There was significant fatigue of subjects in an exercise with physical activity, but there was no reliable influence of performed mental activity on recovery after fatigue.