Decreasing Sedentary Time during Lessons Reduces Obesity in Primary School Children: The Active Movement Study.

INTRODUCTION: School-based exercise interventions targeted at reducing obesity are often successful in the short term, but they are resource-heavy and do not always lead to long-lasting behaviour changes. This study investigated the effect of reducing sedentary time, rather than increasing exercise, on physical activity (PA) behaviours and obesity in primary school children. METHODS: Thirty UK state primary schools participated in this cluster-controlled intervention study (IDACI score = 0.15 ± 0.07, free school meals = 26 ± 9%). Twenty-six intervention and 4 control schools (intervention = 3,529, control = 308 children) completed the Physical Activity Questionnaire for Children (PAQ-C) in terms 1 and 3. Three intervention and 3 control schools (intervention = 219, control = 152 children) also measured waist-to-height ratio (WTHR). The Active Movement Intervention is a school-based programme which integrates non-sedentary behaviours such as standing and walking in the classroom. Data were analysed via ANCOVAs and multiple linear regressions. RESULTS: WTHR was reduced by 8% in the intervention group only (F(2, 285) = 11.387, p < 0.001), and sport participation increased by 10% in the intervention group only (F(1, 232) = 6.982, p = 0.008). Other PAQ-C measures increased significantly in the intervention group, but there was no group*time interaction. Changes in PAQ-C did not predict reductions in WTHR. Instead, the amount of change in WTHR was predicted by intervention group and by baseline WTHR of the pupil, where children with higher baseline WTHR showed greater reductions (F(2, 365) = 77.21, p < 0.001, R2 = 0.30). Socio-economic status (SES), age, or gender did not mediate any of the changes in the PAQ-C or WTHR. CONCLUSION: Reducing sedentary behaviours during school time can be an effective obesity reduction strategy for primary school children who are overweight. The lack of demographic effects suggests that this method can be effective regardless of the school's SES, pupil age, or gender.

Acute and long-term sleep measurements produce opposing results on sleep quality in 8 and 12 hour shift patterns in law enforcement officers.

The occupational demands of law enforcement increase the risk of poor-quality sleep, putting officers at risk of adverse physical and mental health. This cross-sectional study aimed to characterise sleep quality in day workers, 8 and 12 h rotating shift pattern workers. One hundred eighty-six officers volunteered for the study (37 female, age: 41 ± 7). Sleep quality was assessed using the Pittsburgh sleep quality index, actigraphy and the Leeds sleep evaluation questionnaire. The maximal aerobic capacity (VO2max ) was measured on a treadmill via breath-by-breath analysis. There was a 70% overall prevalence of poor sleepers based on Pittsburgh sleep quality index scores, where 8 h shifts exhibited the worst prevalence (92%, p = 0.029), however, there was no difference between age, gender, or role. In contrast, 12 h shifts exhibited the poorest short-term measures, including awakening from sleep (p = 0.039) and behaviour following wakefulness (p = 0.033) from subjective measures, and poorer total sleep time (p = 0.024) and sleep efficiency (p = 0.024) from the actigraphy. High VO2max predicted poorer wake after sleep onset (Rsq = 0.07, p = 0.05) and poorer sleep latency (p = 0.028). There was no relationship between the Pittsburgh sleep quality index scores and any of the short-term measures. The prevalence of poor sleepers in this cohort was substantially higher than in the general population, regardless of shift pattern. The results obtained from the long- and short-term measures of sleep quality yielded opposing results, where long-term perceptions favoured the 12 h pattern, but short-term subjective and objective measures both favoured the 8 h pattern.

Prefrontal cortical activation associated with prospective memory while walking around a real-world street environment.

Rostral PFC (area 10) activation is common during prospective memory (PM) tasks. But it is not clear what mental processes these activations index. Three candidate explanations from cognitive neuroscience theory are: (i) monitoring of the environment; (ii) spontaneous intention retrieval; (iii) a combination of the two. These explanations make different predictions about the temporal and spatial patterns of activation that would be seen in rostral PFC in naturalistic settings. Accordingly, we plotted functional events in PFC using portable fNIRS while people were carrying out a PM task outside the lab and responding to cues when they were encountered, to decide between these explanations. Nineteen people were asked to walk around a street in London, U.K. and perform various tasks while also remembering to respond to prospective memory (PM) cues when they detected them. The prospective memory cues could be either social (involving greeting a person) or non-social (interacting with a parking meter) in nature. There were also a number of contrast conditions which allowed us to determine activation specifically related to the prospective memory components of the tasks. We found that maintaining both social and non-social intentions was associated with widespread activation within medial and right hemisphere rostral prefrontal cortex (BA 10), in agreement with numerous previous lab-based fMRI studies of prospective memory. In addition, increased activation was found within lateral prefrontal cortex (BA 45 and 46) when people were maintaining a social intention compared to a non-social one. The data were then subjected to a GLM-based method for automatic identification of functional events (AIDE), and the position of the participants at the time of the activation events were located on a map of the physical space. The results showed that the spatial and temporal distribution of these events was not random, but aggregated around areas in which the participants appeared to retrieve their future intentions (i.e., where they saw intentional cues), as well as where they executed them. Functional events were detected most frequently in BA 10 during the PM conditions compared to other regions and tasks. Mobile fNIRS can be used to measure higher cognitive functions of the prefrontal cortex in "real world" situations outside the laboratory in freely ambulant individuals. The addition of a "brain-first" approach to the data permits the experimenter to determine not only when haemodynamic changes occur, but also where the participant was when it happened. This can be extremely valuable when trying to link brain and cognition.

An Approach to Neuroimaging Interpersonal Interactions in Mental Health Interventions.

BACKGROUND: Conventional paradigms in clinical neuroscience tend to be constrained in terms of ecological validity, raising several challenges to studying the mechanisms mediating treatments and outcomes in clinical settings. Addressing these issues requires real-world neuroimaging techniques that are capable of continuously collecting data during free-flowing interpersonal interactions and that allow for experimental designs that are representative of the clinical situations in which they occur. METHODS: In this work, we developed a paradigm that fractionates the major components of human-to-human verbal interactions occurring in clinical situations and used functional near-infrared spectroscopy to assess the brain systems underlying clinician-client discourse (N = 30). RESULTS: Cross-brain neural coupling between people was significantly greater during clinical interactions compared with everyday life verbal communication, particularly between the prefrontal cortex (e.g., inferior frontal gyrus) and inferior parietal lobule (e.g., supramarginal gyrus). The clinical tasks revealed extensive increases in activity across the prefrontal cortex, especially in the rostral prefrontal cortex (area 10), during periods in which participants were required to silently reason about the dysfunctional cognitions of the other person. CONCLUSIONS: This work demonstrates a novel experimental approach to investigating the neural underpinnings of interpersonal interactions that typically occur in clinical settings, and its findings support the idea that particular prefrontal systems might be critical to cultivating mental health.

Decreased Exercise-Induced Changes in Prefrontal Cortex Hemodynamics Are Associated With Depressive Symptoms.

People with a depressed mood tend to perform poorly on executive function tasks, which require much of the prefrontal cortex (PFC), an area of the brain which has also been shown to be hypo-active in this population. Recent research has suggested that these aspects of cognition might be improved through physical activity and cognitive training. However, whether the acute effects of exercise on PFC activation during executive function tasks vary with depressive symptoms remains unclear. To investigate these effects, 106 participants were given a cardiopulmonary exercise test (CPET) and were administered a set of executive function tests directly before and after the CPET assessment. The composite effects of exercise on the PFC (all experimental blocks) showed bilateral activation changes in dorsolateral (BA46/9) and ventrolateral (BA44/45) PFC, with the greatest changes occurring in rostral PFC (BA10). The effects observed in right ventrolateral PFC varied depending on level of depressive symptoms (13% variance explained); the changes in activation were less for higher levels. There was also a positive relationship between CPET scores (VO2peak) and right rostral PFC, in that greater activation changes in right BA10 were predictive of higher levels of aerobic fitness (9% variance explained). Since acute exercise ipsilaterally affected this PFC subregion and the inferior frontal gyrus during executive function tasks, this suggests physical activity might benefit the executive functions these subregions support. And because physical fitness and depressive symptoms explained some degree of cerebral upregulation to these subregions, physical activity might more specifically facilitate the engagement of executive functions that are typically associated with hypoactivation in depressed populations. Future research might investigate this possibility in clinical populations, particularly the neural effects of physical activity used in combination with mental health interventions.

The role of anterior prefrontal cortex (area 10) in face-to-face deception measured with fNIRS.

Anterior prefrontal cortex (PFC, Brodmann area 10) activations are often, but not always, found in neuroimaging studies investigating deception, and the precise role of this area remains unclear. To explore the role of the PFC in face-to-face deception, we invited pairs of participants to play a card game involving lying and lie detection while we used functional near infrared spectroscopy (fNIRS) to record brain activity in the PFC. Participants could win points for successfully lying about the value of their cards or for detecting lies. We contrasted patterns of brain activation when the participants either told the truth or lied, when they were either forced into this or did so voluntarily and when they either succeeded or failed to detect a lie. Activation in the anterior PFC was found in both lie production and detection, unrelated to reward. Analysis of cross-brain activation patterns between participants identified areas of the PFC where the lead player's brain activity synchronized their partner's later brain activity. These results suggest that during situations that involve close interpersonal interaction, the anterior PFC supports processing widely involved in deception, possibly relating to the demands of monitoring one's own and other people's behaviour.

Short-Term Fasting Selectively Influences Impulsivity in Healthy Individuals.

Previous research has shown that short-term fasting in healthy individuals is associated with changes in risky decision-making. The current experiment was designed to examine the influence of short-term fasting in healthy individuals on four types of impulsivity: reflection impulsivity, risky decision-making, delay aversion, and action inhibition. Participants were tested twice, once when fasted for 20 h, and once when satiated. Participants demonstrated impaired action inhibition when fasted; committing significantly more errors of commission during a food-related Affective Shifting Task. Participants also displayed decreased reflection impulsivity when fasted, opening significantly more boxes during the Information Sampling Task (IST). There were no significant differences in performance between fasted and satiated sessions for risky decision-making or delay aversion. These findings may have implications for understanding eating disorders such as Bulimia Nervosa (BN). Although BN has been characterized as a disorder of poor impulse control, inconsistent findings when comparing individuals with BN and healthy individuals on behavioral measures of impulsivity question this characterization. Since individuals with BN undergo periods of short-term fasting, the inconsistent findings could be due to differences in the levels of satiation of participants. The current results indicate that fasting can selectively influence performance on the IST, a measure of impulsivity previously studied in BN. However, the results from the IST were contrary to the original hypothesis and should be replicated before specific conclusions can be made.

Mentalising and conversation-following in autism.

Some people with autism spectrum disorders have been observed to experience difficulties with making correct inferences in conversations in social situations. However, the nature and origin of their problem is rarely investigated. This study used manipulations of video stimuli to investigate two questions. The first question was whether it is the number of people involved in social situations, that is, the source of problems in following conversations, or whether it is the increased mentalising demands required to comprehend interactions between several people. The second question asked was whether the nature and pattern of the errors that autism spectrum disorder participants show are the same as typically developing people make when they make an error. In total, 43 typically developed adults and 30 adults diagnosed with autism spectrum disorder were studied. We found that it was the amount of mentalising required, rather than the number of people involved, which caused problems for people with autism spectrum disorder in following conversations. Furthermore, the autism spectrum disorder participants showed a more heterogeneous pattern of errors, showing less agreement among themselves than the typically developed group as to which test items were hardest. So, fully understanding the observed behaviour consequent upon weakness in mentalising ability in people with autism spectrum disorders requires consideration of factors other than mentalising.

The present and future use of functional near-infrared spectroscopy (fNIRS) for cognitive neuroscience.

The past few decades have seen a rapid increase in the use of functional near-infrared spectroscopy (fNIRS) in cognitive neuroscience. This fast growth is due to the several advances that fNIRS offers over the other neuroimaging modalities such as functional magnetic resonance imaging and electroencephalography/magnetoencephalography. In particular, fNIRS is harmless, tolerant to bodily movements, and highly portable, being suitable for all possible participant populations, from newborns to the elderly and experimental settings, both inside and outside the laboratory. In this review we aim to provide a comprehensive and state-of-the-art review of fNIRS basics, technical developments, and applications. In particular, we discuss some of the open challenges and the potential of fNIRS for cognitive neuroscience research, with a particular focus on neuroimaging in naturalistic environments and social cognitive neuroscience.

Executive function in high-functioning autism: Decision-making consistency as a characteristic gambling behaviour.

Restricted and repetitive patterns of behaviours, interests, or activities are a critical diagnostic criterion for autism spectrum disorder (ASD). Previous studies using gambling paradigms with ASD populations have identified that, unlike typically developed control participants, people with a diagnosis of ASD tend to maintain particular response patterns regardless of the magnitude of potential outcomes to uncertain gains or losses. Here we designed a gambling test that permitted calculation of the response consistency in gambling choices in situations that presented varying expected outcomes in terms of gains or losses. The task was administered to 33 adults with a diagnosis of ASDs and compared to a group of 47 typically-developed (TD) control participants who were matched for age and IQ. When presented with choices where participants could either make a risky gamble or a safe choice in terms of gains or losses (e.g., 20% chance of winning £5 vs. 100% chance of winning £1), the ASD participants did not differ from the TDs in their overall risk-taking behaviour. However, they were more consistent in their individual choices from trial to trial. Furthermore, the proportion of participants who either implemented an invariate response strategy (e.g., either always choosing the most risky or most "safe" option) was significantly higher in the ASD group compared with the controls. Additionally, while the ASD group were slower to make their responses in the win frame and the first half of the lose frame, by the end of the task their decision times were the same as the TD controls. These findings suggest that the ASD tendency towards repetitive behaviour may demonstrate itself even in high-level decision-making tasks, which needs to be understood if we are to be sure what such tasks are measuring.

Fifty Years of Prefrontal Cortex Research: Impact on Assessment.

Our knowledge of the functions of the prefrontal cortex, often called executive, supervisory, or control, has been transformed over the past 50 years. After operationally defining terms for clarification, we review the impact of advances in functional, structural, and theoretical levels of understanding upon neuropsychological assessment practice as a means of identifying 11 principles/challenges relating to assessment of executive function. Three of these were already known 50 years ago, and 8 have been confirmed or emerged since. Key themes over this period have been the emergence of the use of naturalistic tests to address issues of "ecological validity"; discovery of the complexity of the frontal lobe control system; invention of new tests for clinical use; development of key theoretical frameworks that address the issue of the role of prefrontal cortex systems in the organization of human cognition; the move toward considering brain systems rather than brain regions; the advent of functional neuroimaging, and its emerging integration into clinical practice. Despite these huge advances, however, practicing neuropsychologists are still desperately in need of new ways of measuring executive function. We discuss pathways by which this might happen, including decoupling the two levels of explanation (information processing; brain structure) and integrating very recent technological advances into the neuropsychologist's toolbox. (JINS, 2017, 23, 755-767).

A novel GLM-based method for the Automatic IDentification of functional Events (AIDE) in fNIRS data recorded in naturalistic environments.

Recent technological advances have allowed the development of portable functional Near-Infrared Spectroscopy (fNIRS) devices that can be used to perform neuroimaging in the real-world. However, as real-world experiments are designed to mimic everyday life situations, the identification of event onsets can be extremely challenging and time-consuming. Here, we present a novel analysis method based on the general linear model (GLM) least square fit analysis for the Automatic IDentification of functional Events (or AIDE) directly from real-world fNIRS neuroimaging data. In order to investigate the accuracy and feasibility of this method, as a proof-of-principle we applied the algorithm to (i) synthetic fNIRS data simulating both block-, event-related and mixed-design experiments and (ii) experimental fNIRS data recorded during a conventional lab-based task (involving maths). AIDE was able to recover functional events from simulated fNIRS data with an accuracy of 89%, 97% and 91% for the simulated block-, event-related and mixed-design experiments respectively. For the lab-based experiment, AIDE recovered more than the 66.7% of the functional events from the fNIRS experimental measured data. To illustrate the strength of this method, we then applied AIDE to fNIRS data recorded by a wearable system on one participant during a complex real-world prospective memory experiment conducted outside the lab. As part of the experiment, there were four and six events (actions where participants had to interact with a target) for the two different conditions respectively (condition 1: social-interact with a person; condition 2: non-social-interact with an object). AIDE managed to recover 3/4 events and 3/6 events for conditions 1 and 2 respectively. The identified functional events were then corresponded to behavioural data from the video recordings of the movements and actions of the participant. Our results suggest that "brain-first" rather than "behaviour-first" analysis is possible and that the present method can provide a novel solution to analyse real-world fNIRS data, filling the gap between real-life testing and functional neuroimaging.

The Intention-Outcome Asymmetry Effect.

Knowledge of intention and outcome is integral to making judgments of responsibility, blame, and causality. Yet, little is known about the effect of conflicting intentions and outcomes on these judgments. In a series of four experiments, we combine good and bad intentions with positive and negative outcomes, presenting these through everyday moral scenarios. Our results demonstrate an asymmetry in responsibility, causality, and blame judgments for the two incongruent conditions: well-intentioned agents are regarded more morally and causally responsible for negative outcomes than ill-intentioned agents are held for positive outcomes. This novel effect of an intention-outcome asymmetry identifies an unexplored aspect of moral judgment and is partially explained by extra inferences that participants make about the actions of the moral agent.

Confabulation in children with autism.

Some children with high-functioning autistic spectrum conditions (ASC) have been noted clinically to produce accounts and responses akin to confabulations in neurological patients. Neurological confabulation is typically associated with abnormalities of the frontal lobes and related structures, and some forms have been linked to poor performance on source monitoring and executive function tasks. ASC has also been linked to atypical development of the frontal lobes, and impaired performance on source monitoring and executive tasks. But confabulation in autism has not to our knowledge previously been examined experimentally. So we investigated whether patterns of confabulation in autism might share similarities with neurologically-based confabulation. Tests of confabulation elicitation, source monitoring (reality monitoring, plus temporal and task context memory) and executive function were administered to four adolescents with ASC who had previously been noted to confabulate spontaneously in everyday life. Scores were compared to a typically developing (TD) and an ASC control group. One confabulating participant was significantly impaired at reality monitoring, and one was significantly worse at a task context test, relative to both the ASC and TD controls. Three of the confabulators showed impairment on measures of executive function (Brixton test; Cognitive Estimates test; Hayling Test B errors) relative to both control groups. Three were significantly poorer than the TD controls on two others (Hayling A and B times), but the ASC control group was also significantly slower at this test than the TD controls. Compared to TD controls, two of the four confabulating participants produced an abnormal number of confabulations during a confabulation elicitation questionnaire, where the ASC controls and TD controls did not differ from each other. These results raise the possibility that in at least some cases, confabulation in autism may be less related to social factors than it is to impaired source memory or poor executive function.

Does Faux Pas Detection in Adult Autism Reflect Differences in Social Cognition or Decision-Making Abilities?

43 typically-developed adults and 35 adults with ASD performed a cartoon faux pas test. Adults with ASD apparently over-detected faux pas despite good comprehension abilities, and were generally slower at responding. Signal detection analysis demonstrated that the ASD participants had significantly greater difficulty detecting whether a cartoon depicted a faux pas and showed a liberal response bias. Test item analysis demonstrated that the ASD group were not in agreement with a reference control group (n = 69) about which non-faux pas items were most difficult. These results suggest that the participants with ASD had a primary problem with faux pas detection, but that there is another factor at work, possibly compensatory, that relates to their choice of a liberal response criterion.

Increased set shifting costs in fasted healthy volunteers.

We investigated the impact of temporary food restriction on a set shifting task requiring participants to judge clusters of pictures against a frequently changing rule. 60 healthy female participants underwent two testing sessions: once after fasting for 16 hours and once in a satiated state. Participants also completed a battery of questionnaires (Hospital Anxiety and Depression Scale [HADS]; Persistence, Perseveration and Perfectionism Questionnaire [PPPQ-22]; and Eating Disorders Examination Questionnaire [EDE-Q6]). Set shifting costs were significantly increased after fasting; this effect was independent of self-reported mood and perseveration. Furthermore, higher levels of weight concern predicted a general performance decrement under conditions of fasting. We conclude that relatively short periods of fasting can lead to set shifting impairments. This finding may have relevance to studies of development, individual differences, and the interpretation of psychometric tests. It also could have implications for understanding the etiology and maintenance of eating disorders, in which impaired set shifting has been implicated.

Does "task difficulty" explain "task-induced deactivation?".

The "default mode network" is commonly described as a set of brain regions in which activity is suppressed during relatively demanding, or difficult, tasks. But what sort of tasks are these? We review some of the contrasting ways in which a task might be assessed as being difficult, such as error rate, response time, propensity to interfere with performance of other tasks, and requirement for transformation of internal representations versus accumulation of perceptual information. We then describe a fMRI study in which 18 participants performed two "stimulus-oriented" tasks, where responses were directly cued by visual stimuli, alongside a "stimulus-independent" task, with a greater reliance on internally generated information. When indexed by response time and error rate, the stimulus-independent task was intermediate in difficulty between the two stimulus-oriented tasks. Nevertheless, BOLD signal in medial rostral prefrontal cortex (MPFC) - a prominent part of the default mode network - was reduced in the stimulus-independent condition in comparison with both the more difficult and the less difficult stimulus-oriented conditions. By contrast, other regions of the default mode network showed greatest deactivation in the difficult stimulus-oriented condition. There was therefore significant functional heterogeneity between different default mode regions. We conclude that task difficulty - as measured by response time and error rate - does not provide an adequate account of signal change in MPFC. At least in some circumstances, a better predictor of MPFC activity is the requirement of a task for transformation and manipulation of internally represented information, with greatest MPFC activity in situations predominantly requiring attention to perceptual information.

Rostral prefrontal cortex and the focus of attention in prospective memory.

Prospective memory (PM) denotes the function to realize intentions after a delay while being immersed in distracting ongoing (OG) activity. Here, we scrutinize the often-reported involvement of rostral prefrontal cortex (rPFC; approximating Brodmann area 10) in such situations: This region might mediate attention between external stimuli and the internally maintained intention, that is, between stimulus-oriented (SO) and stimulus-independent (SI) processing. Using functional magnetic resonance imaging (fMRI) we orthogonally crossed 1) PM versus OG activity only, with 2) SO versus SI attention. In support of the hypothesis, common regions of medial rPFC exhibited greater blood oxygen level-dependent (BOLD) signal for the contrasts of both OG task only versus PM and SO versus SI attending. However, activation related to the former contrast extended more superiorly, suggesting a functional gradient along a dorsal-ventral axis within this region. Moreover, region-of-interest analyses revealed that PM versus OG task only was associated with greater BOLD signal in left lateral rPFC, reflecting the requirement to maintain delayed intentions. Distinct aspects of this region were also transiently engaged at transitions between SO and SI conditions. These results are consistent with the hypothesis that some of the rostral prefrontal signal changes associated with PM performance reflect relative differences in SO versus SI processing.