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Spectral dataset of natural objects’ reflectance from the Southern cone of South America
Abstract The reflection in natural objects mediates an important fraction of the light reaching animal photoreceptors. Knowledge of the spectral properties of natural objects is increasingly valuable for different research fields. Measured datasets of natural objects’ reflectance can offer insights into fundamental and applied research questions, contributing to investigations from coloration and color vision to color analysis and representation. Thus, datasets of natural objects’ reflectance across different locations are crucial to assessing the universality and variability of physical visual inputs in diverse environments. However, the Southern Hemisphere is notably underrepresented in publicly available datasets of natural objects. To address this gap, we present a spectral dataset of natural objects’ reflectance from the Southern cone of South America, specifically Northwestern Argentina. Our dataset encompasses 532 samples representing diverse natural objects such as barks, flowers, fruits, leaves, plant fruits, stones, and animal specimens, including birds, beetles, and butterflies. By openly sharing this dataset, as a publicly available online resource, we aim to facilitate research across various disciplines, from evolutionary biology to industrial applications.
Perceptions and experiences of mental health support for ambulance trust employees
Background: Mental ill health among ambulance staff is widespread. Evidence suggests that, with the right support, employees experiencing mental ill health can continue to work, symptom severity can be reduced and suicide prevented. Aims: To investigate ambulance staff perceptions and experiences of organisational mental health support. Methods: A cross-sectional online survey investigated work-related stressful life events and their potential psychological impact. The survey also examined staff perceptions and experiences of organisational support and acceptability of a proposed wellbeing intervention offering mandatory time to talk at work. Findings: A total of 540 ambulance staff responded. The majority reported having experienced work-related stressful life events (n=444; 82%). Associated psychological symptoms appeared to persist for years. Perceptions about organisational support related to support uptake. Stigma, fear and embarrassment were reported as barriers to disclosure and help-seeking. Mandatory time to talk at work would be acceptable (n=400; 74%). Conclusion: The association between work-related stressful events and psychological symptoms underscores the need for interventions supported at an organisation level.
The romanticisation of mental health problems in adolescents and its implications: a narrative review.
Romanticisation is the perception and portrayal of a phenomenon as more attractive, interesting, cool, profound or desirable than it really is. There are concerns that mental health problems are increasingly romanticised, particularly among adolescents, but there is limited research on this topic. This narrative review investigated: (1) what romanticisation is in the context of adolescent mental health problems, (2) why adolescents might romanticise mental health problems, (3) the implications of romanticising mental health problems in adolescence, and (4) what interventions might reduce this phenomenon. Sixty-one publications were reviewed, including qualitative and quantitative analyses, cross-sectional and longitudinal self-report studies and conceptual reviews. Most investigated romanticisation of mental health problems online, with most researchers situated in a Western context. Identity formation, popular media influences and peer influences arose as potential explanatory factors. Negative outcomes to romanticisation were indicated, including the reinforcement of mental health problems and reduced help-seeking; few interventions to reduce the phenomenon have been proposed to date.
Development and validation of a measure of concrete and abstract thinking
Abstract-analytical thinking, which characterizes rumination and worry, has been shown to be a risk and maintenance factor for psychological disorders, yet there are no accessible, reliable measures that can be easily administered to assess this cognitive process. Student paramedics are at elevated risk of developing mental health difficulties associated with rumination and worry due to the nature of their work. The current study describes the development and validation of the Concrete and Abstract Thinking measure (CAT) in a sample of student paramedics. The scenario-based CAT measure was systematically developed. An initial pool of scenarios was generated based on previous research and the Worry Domains Questionnaire. A total of 14 paramedics, inclusive of student paramedics, evaluated the content of the scenarios. Final items were determined based on best-fit using confirmatory factor analysis. Two-hundred student paramedics completed the CAT measure and associated measures and 96.6% completed it again for test-retest reliability. Abstract items of the CAT measure showed good internal consistency (α=.87), test-retest reliability (ICC = .88) and good factorial, construct and criterion validity. The CAT measure was significantly associated with measures of perseverative thinking (r = .52), rumination (r = .42), worry (r = .50), depression (r = .32), anxiety (r = .41), posttraumatic stress disorder (r = .23), self-efficacy (r = -.32) and resilience (r = -.30). Overall, the CAT measure showed robust psychometric properties, evidencing good validity and reliability. The CAT measure offers a user-friendly, valid, reliable and population-specific measure of concrete and abstract thinking whilst also providing a model of how abstract thinking could be assessed in a range of populations at risk of developing mental health disorders.
Cognitive and neuropsychiatric profiles distinguish atypical parkinsonian syndromes.
Atypical parkinsonian syndromes are distinguished from Parkinson's disease by additional neurological signs and characteristic underlying neuropathology. However, they can be diagnostically challenging, rapidly progressive, and are often diagnosed late in disease course. Their different demographic features and prognoses are well studied, but the accompanying cognitive and psychiatric features may also facilitate diagnosis. Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) may cause cognitive and behavioural manifestations that overlap with frontotemporal dementia, including non-fluent aphasia, apathy and impulsivity. Clinical diagnostic criteria have limited sensitivity, with pathologically confirmed PSP often having presented an initial clinical syndrome other than PSP-Richardson's syndrome. Here we integrate cross-sectional multi-centre baseline data from the PROSPECT and Oxford Discovery cohorts. This allowed us to compare cognitive and psychiatric features across a total of 1138 people with PSP, CBS, multiple-system atrophy (MSA), and idiopathic Parkinson's disease (PD). Data from the different cohorts were harmonised and compared using multiple linear regression. There were five key results. 1. Different syndromes showed distinctive cognitive profiles, using readily applicable 'bedside' screening tools. Frontal executive dysfunction was most evident in PSP, visuospatial deficits in CBS, with milder deficits in memory and executive function in MSA, as compared with PD. 2. The most prevalent neuropsychiatric features were depression and anxiety in CBS, apathy in PSP, with sleep disturbances common in PD. As expected, apathy correlated positively with impulsivity across all disorders. Neuropsychiatric features were generally better at discriminating between atypical parkinsonian syndromes than were the cognitive domains. 3. Both cognitive function and motor severity declined with disease duration, and motor function predicted cognition in PSP, CBS and PD but not in MSA, suggesting that in MSA cognitive and motor dysfunction are decoupled. 4. Plasma neurofilament light chain (NFL) levels, measured in a subset of patients, correlated with cognitive deficits in PSP, but not motor deficits. 5. Cognitive deficits contributed to the impairment in activities of daily living after controlling for motor severity, with every two points on the MoCA worsening the Schwab and England score by one point. In anticipation of future neuroprotective therapies, we present a classifier to improve diagnostic accuracy for atypical parkinsonian syndromes in vivo. Longitudinal cohort studies with resources for neuropathological gold-standard diagnosis remain important to validate better diagnostic tools for people with PSP, CBD, MSA and atypical parkinsonism.
An orexin-sensitive subpopulation of layer 6 neurons regulates cortical excitability and anxiety behaviour.
Cortical layer 6 neurons are the only projection neuron population in the cortical mantle known to electrophysiologically respond to orexin-a neuropeptide involved in cortical arousal and emotive behaviour. These neurons exhibit extensive intercortical and thalamic projections, yet the exact mechanisms underlying these responses are not fully understood. We hypothesize that cortical circuits activated by orexin sensitive L6 neurons in the medial prefrontal cortex (mPFC) are responsible for detecting salient features of sensory stimuli and are therefore involved in regulating emotional states. Here, we show that Drd1a-Cre+ neurons in the mPFC are selectively sensitive to orexin and gate the activation of the prefrontal network in vivo. Moreover, we demonstrated that chronically "silencing" this subpopulation of L6 neurons (Drd1a-Cre+/+:Snap25fl/fl) across the cortical mantle from birth abolishes the orexin-induced prefrontal activation. Consequently, the chronic silencing of these neurons had strong anxiolytic effects on several anxiety-related behavioural paradigms, indicating that orexin-responsive L6 neurons modulate emotional states and may be a substrate for anxiety regulation.
Improving executive function during toddlerhood: A systematic review and meta-analysis of parent-led interventions
Individual differences in executive functions are detectable in the first year of life and continue to develop throughout the preschool years. Psychological science suggests that executive function is malleable, with parents playing a crucial role as potential agents of change. However, the effectiveness of interventions aimed at teaching parents how to enhance their children's executive function during the preschool years remains unclear. To address this gap, we pre-registered a systematic review and meta-analysis of the literature on parent/caregiver-led interventions designed to foster children's executive function from ages 2 to 5 years. We conducted an extensive search across 12 databases spanning disciplines such as developmental psychology, education, and policy. After screening over 11,000 papers, 12 studies met our inclusion criteria. These interventions included home visits, in-person group sessions for parents/caregivers, or a combination of both. Our meta-analysis, which included 8 studies with a total of 1,815 participants − 946 in the treatment group and 869 in the control group − revealed no statistically significant difference between the treatment and control groups overall. A follow-up analysis of two studies using the same outcome measure for Effortful Control showed a small to moderate positive effect that was statistically significant [SMD = 0.28, 95 % CI (0.08, 0.47)]. We provide recommendations for improving the evidence base in this area, emphasising the need for more rigorous and standardised methodologies in future research. This review underscores the potential of parents as key facilitators in the development of their children's executive functions and highlights promising directions for future interventions.
Cognitive and behavioural processes in adolescent panic disorder.
BACKGROUND: Improved understanding of the cognitive and behavioural processes underpinning panic disorder (PD) in adolescents could improve identification and treatment. AIMS: We investigated whether the processes outlined in Clark's (1986) cognitive model of PD are observed in adolescents with PD, are specific to PD, and predict symptom severity. METHOD: We recruited three groups of adolescents (12-17 years): 34 with a PD diagnosis, 33 with another anxiety disorder excluding PD ('clinical control'), and 34 scoring below the clinical cut-off on a measure of anxiety symptoms ('community control'). Participants self-reported on measures of PD symptom severity, catastrophic cognitions, bodily sensation fear, and safety-seeking behaviours. RESULTS: The PD group reported significantly higher levels of catastrophic cognitions and safety-seeking behaviours than both control groups. They reported significantly higher levels of bodily sensation fear compared with the community but not the clinical control group. All process measures positively predicted PD symptom severity across all groups. CONCLUSIONS: We found evidence of catastrophic cognitions and safety-seeking behaviours as PD-specific processes in adolescents which predict symptom severity. Bodily sensation fear also predicted symptom severity. Findings support Clark's cognitive model of PD in adolescents and suggest that catastrophic cognitions and safety behaviours may be targets for adolescent PD treatment.
Human gaze tracks attentional focusing in memorized visual space.
Brain areas that control gaze are also recruited for covert shifts of spatial attention1-9. In the external space of perception, there is a natural ecological link between the control of gaze and spatial attention, as information sampled at covertly attended locations can inform where to look next2,10,11. Attention can also be directed internally to representations held within the spatial layout of visual working memory12-16. In such cases, the incentive for using attention to direct gaze disappears, as there are no external targets to scan. Here we investigate whether the oculomotor system of the brain also participates in attention focusing within the internal space of memory. Paradoxically, we reveal this participation through gaze behaviour itself. We demonstrate that selecting an item from visual working memory biases gaze in the direction of the memorized location of that item, despite there being nothing to look at and location memory never explicitly being probed. This retrospective 'gaze bias' occurs only when an item is not already in the internal focus of attention, and it predicts the performance benefit associated with the focusing of internal attention. We conclude that the oculomotor system also participates in focusing attention within memorized space, leaving traces all the way to the eyes.
Confidence and Insight into Working Memories Are Shaped by Attention and Recent Performance.
Working memory is capacity limited, and our ability to access information from working memory is variable, but selective attention to working memory contents can improve performance. People are able to make introspective judgments regarding the quality of their memories, and these judgments are linked to objective memory performance. However, it remains unknown whether benefits of internally directed attention on memory performance occur alongside commensurate changes in introspective judgments. Across two experiments, we used retrospective cues (retrocues) during working-memory maintenance to direct attention to items in memory. We then examined their consequence on introspective judgments. In the second experiment, we provided trial-wise feedback on performance. We found that selective attention improved confidence judgments and not just performance of the probed item. We were also able to judge participants' genuine insight into working-memory contents through the correlation between confidence judgments and memory quality. Neurophysiologically, alpha desynchronization correlated first with memory error and then confidence during retrocueing, suggesting a sequential process of attentional enhancement of memory contents and introspective insight. Furthermore, we showed that participants can use feedback on the accuracy of confidence judgments to update their beliefs across time, according to performance. Our results emphasize flexibility in working memory by showing we can selectively modulate our confidence about its contents based on internally directed attention or objective feedback.
Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: a cross-sectional study.
BACKGROUND: Exercise is known to be associated with reduced risk of all-cause mortality, cardiovascular disease, stroke, and diabetes, but its association with mental health remains unclear. We aimed to examine the association between exercise and mental health burden in a large sample, and to better understand the influence of exercise type, frequency, duration, and intensity. METHODS: In this cross-sectional study, we analysed data from 1 237 194 people aged 18 years or older in the USA from the 2011, 2013, and 2015 Centers for Disease Control and Prevention Behavioral Risk Factors Surveillance System survey. We compared the number of days of bad self-reported mental health between individuals who exercised and those who did not, using an exact non-parametric matching procedure to balance the two groups in terms of age, race, gender, marital status, income, education level, body-mass index category, self-reported physical health, and previous diagnosis of depression. We examined the effects of exercise type, duration, frequency, and intensity using regression methods adjusted for potential confounders, and did multiple sensitivity analyses. FINDINGS: Individuals who exercised had 1·49 (43·2%) fewer days of poor mental health in the past month than individuals who did not exercise but were otherwise matched for several physical and sociodemographic characteristics (W=7·42 × 1010, p<2·2 × 10-16). All exercise types were associated with a lower mental health burden (minimum reduction of 11·8% and maximum reduction of 22·3%) than not exercising (p<2·2 × 10-16 for all exercise types). The largest associations were seen for popular team sports (22·3% lower), cycling (21·6% lower), and aerobic and gym activities (20·1% lower), as well as durations of 45 min and frequencies of three to five times per week. INTERPRETATION: In a large US sample, physical exercise was significantly and meaningfully associated with self-reported mental health burden in the past month. More exercise was not always better. Differences as a function of exercise were large relative to other demographic variables such as education and income. Specific types, durations, and frequencies of exercise might be more effective clinical targets than others for reducing mental health burden, and merit interventional study. FUNDING: Cloud computing resources were provided by Microsoft.
Concurrent visual and motor selection during visual working memory guided action.
Visual working memory enables us to hold onto past sensations in anticipation that these may become relevant for guiding future actions. Yet laboratory tasks have treated visual working memories in isolation from their prospective actions and have focused on the mechanisms of memory retention rather than utilization. To understand how visual memories become used for action, we linked individual memory items to particular actions and independently tracked the neural dynamics of visual and motor selection when memories became used for action. This revealed concurrent visual-motor selection, engaging appropriate visual and motor brain areas at the same time. Thus we show that items in visual working memory can invoke multiple, item-specific, action plans that can be accessed together with the visual representations that guide them, affording fast and precise memory-guided behavior.
A quantitative model of trust as a predictor of social group sizes and its implications for technology
The human capacity for working together and with tools builds on cognitive abilities that, while not unique to humans, are most developed in humans both in scale and plasticity. Our capacity to engage with collaborators and with technology requires a continuous expenditure of attentive work that we show may be understood in terms of what is heuristically argued as ‘trust’ in socio-economic fields. By adopting a ‘social physics’ of information approach, we are able to bring dimensional analysis to bear on an anthropological-economic issue. The cognitive-economic trade-off between group size and rate of attention to detail is the connection between these. This allows humans to scale cooperative effort across groups, from teams to communities, with a trade-off between group size and attention. We show here that an accurate concept of trust follows a bipartite ‘economy of work’ model, and that this leads to correct predictions about the statistical distribution of group sizes in society. Trust is essentially a cognitive-economic issue that depends on the memory cost of past behaviour and on the frequency of attentive policing of intent. All this leads to the characteristic ‘fractal’ structure for human communities. The balance between attraction to some alpha attractor and dispersion due to conflict fully explains data from all relevant sources. The implications of our method suggest a broad applicability beyond purely social groupings to general resource constrained interactions, e.g. in work, technology, cybernetics, and generalized socio-economic systems of all kinds.