Immersive virtual reality as a novel approach to investigate the association between adverse events and adolescent paranoid ideation.

PURPOSE: Paranoid ideation is common among adolescents, yet little is known about the precursors. Using a novel immersive virtual reality (VR) paradigm, we tested whether experiences of bullying, and other interpersonal/threatening events, are associated with paranoid ideation to a greater degree than other types of (i) non-interpersonal events or (ii) adverse childhood experiences. METHODS: Self-reported exposure to adverse life events and bullying was collected on 481 adolescents, aged 11-15. We used mixed effects (multilevel) linear regression to estimate the magnitude of associations between risk factors and paranoid ideation, assessed by means of adolescents' reactions to ambiguously behaving avatars in a VR school canteen, adjusting for putative confounders (gender, year group, ethnicity, free school meal status, place of birth, family mental health problems). RESULTS: Lifetime exposure to interpersonal/threatening events, but not non-interpersonal events or adverse circumstances, was associated with higher levels of state paranoid ideation, with further evidence that the effect was cumulative (1 type: ϐadj 0.07, 95% CI -0.01-0.14; 2 types: ϐadj 0.14, 95% CI 0.05-0.24; 3 + types: ϐadj 0.24, 95% CI 0.12-0.36). More tentatively, for girls, but not boys, recent bullying was associated with heightened paranoid ideation with effect estimates ranging from ϐadj 0.06 (95% CI -0.02-0.15) for physical bullying to ϐadj 0.21 (95% CI 0.10-0.32) for cyber bullying. CONCLUSIONS: Our data suggest a degree of specificity for adversities involving interpersonal threat or hostility, i.e. those that involve unwanted interference and/or attempted control of an individual's personal boundaries being associated with heightened levels of state paranoid ideation among adolescents.

Prevalence and Factors Associated with Behavioral Problems in 5-Year-Old Children Born with Cleft Lip and/or Palate from the Cleft Collective.

OBJECTIVES: To determine the UK prevalence of behavioral problems in 5-year-old children born with isolated or syndromic cleft lip and/or palate (CL/P) compared to the general population and identify potentially associated factors. DESIGN: Observational study using questionnaire data from the Cleft Collective 5-Year-Old Cohort study and three general population samples. MAIN OUTCOME MEASURE: The Strengths and Difficulties Questionnaire (SDQ). PARTICIPANTS: Mothers of children (age: 4.9-6.8 years) born with CL/P (n = 325). UK general population cohorts for SDQ scores were: Millennium Cohort Study (MCS) (n = 12 511), Office of National Statistics (ONS) normative school-age SDQ data (n = 5855), and Avon Longitudinal Study of Parents and Children (ALSPAC) (n = 9386). RESULTS: By maternal report, 14.2% of children born with CL/P were above clinical cut-off for behavioral problems, which was more likely than in general population samples: 7.5% of MCS (OR = 2.05 [1.49-2.82], P < 0.001), 9.8% of ONS (OR = 1.52 [1.10-2.09], P = 0.008), and 6.6% of ALSPAC (OR = 2.34 [1.70-3.24], P < 0.001). Children in the Cleft Collective had higher odds for hyperactivity, emotional and peer problems, and less prosocial behaviors. Maternal stress, lower maternal health-related quality of life and family functioning, receiving government income support, and maternal smoking showed evidence of association (OR range: 4.41-10.13) with behavioral problems, along with maternal relationship status, younger age, and lower education (OR range: 2.34-3.73). CONCLUSIONS: Findings suggest elevated levels of behavioral problems in children born with CL/P compared to the general population with several associated maternal factors similar to the general population.

Feedback loops between 3D vegetation structure and ecological functions of animals.

Ecosystems function in a series of feedback loops that can change or maintain vegetation structure. Vegetation structure influences the ecological niche space available to animals, shaping many aspects of behaviour and reproduction. In turn, animals perform ecological functions that shape vegetation structure. However, most studies concerning three-dimensional vegetation structure and animal ecology consider only a single direction of this relationship. Here, we review these separate lines of research and integrate them into a unified concept that describes a feedback mechanism. We also show how remote sensing and animal tracking technologies are now available at the global scale to describe feedback loops and their consequences for ecosystem functioning. An improved understanding of how animals interact with vegetation structure in feedback loops is needed to conserve ecosystems that face major disruptions in response to climate and land-use change.

Childhood attention-deficit hyperactivity disorder problems and mid-life cardiovascular risk: prospective population cohort study.

BACKGROUND: It is well-known that childhood attention-deficit hyperactivity disorder (ADHD) is associated with later adverse mental health and social outcomes. Patient-based studies suggest that ADHD may be associated with later cardiovascular disease (CVD) but the focus of preventive interventions is unclear. It is unknown whether ADHD leads to established cardiovascular risk factors because so few cohort studies measure ADHD and also follow up to an age where CVD risk is evident. AIMS: To examine associations between childhood ADHD problems and directly measured CVD risk factors at ages 44/45 years in a UK population-based cohort study (National Child Development Study) of individuals born in 1958. METHOD: Childhood ADHD problems were defined by elevated ratings on both the parent Rutter A scale and a teacher-rated questionnaire at age 7 years. Outcomes were known cardiovascular risk factors (blood pressure, lipid measurements, body mass index and smoking) at the age 44/45 biomedical assessment. RESULTS: Of the 8016 individuals assessed both during childhood and at the biomedical assessment 3.0% were categorised as having childhood ADHD problems. ADHD problems were associated with higher body mass index (B = 0.92 kg/m2, s.d. = 0.27-1.56), systolic (3.5 mmHg, s.d. = 1.4-5.6) and diastolic (2.2 mmHg, s.d. = 0.8-3.6) blood pressure, triglyceride levels (0.24 mol/l, s.d. = 0.02-0.46) and being a current smoker (odds ratio OR = 1.6, s.d. = 1.2-2.1) but not with LDL cholesterol. CONCLUSIONS: Childhood ADHD problems predicted multiple cardiovascular risk factors by mid-life. These findings, when taken together with previously observed associations with cardiovascular disease in registries, suggest that individuals with ADHD could benefit from cardiovascular risk monitoring, given these risk factors are modifiable with timely intervention.

Co-development of attention deficit hyperactivity disorder and autistic trait trajectories from childhood to early adulthood.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) and autism, defined as traits or disorders, commonly co-occur. Developmental trajectories of ADHD and autistic traits both show heterogeneity in onset and course, but little is known about how symptom trajectories co-develop into adulthood. METHODS: Using data from a population cohort, the Avon Longitudinal Study of Parents and Children, we examined correlations between ADHD and autistic traits across development, using the Social Communication Disorders Checklist and ADHD subscale of the Strengths and Difficulties Questionnaire. We modelled joint developmental trajectories of parent-reported ADHD and autistic traits between 4 and 25 years, then characterised trajectory classes based on sociodemographic, perinatal, psychopathology, cognition and social functioning variables and tested for associations with neurodevelopmental/psychiatric polygenic scores (PGS). RESULTS: Three classes of trajectories were identified; a typically developing majority with low-stable ADHD-autistic traits (87%), a male-predominant subgroup with child/adolescent-declining traits (6%) and a subgroup with late-emerging traits (6%). ADHD-autistic trait correlations were greatest in young adulthood for the two nontypically developing classes. There were higher rates of emotional and conduct problems, low IQ, childhood seizures and poor social functioning in the declining and late-emerging classes compared to the low-stable class. Emotional, conduct and peer problems were more prevalent during childhood in the childhood/adolescent-declining class compared to other classes, but were more prevalent in young adulthood in the late-emerging class. Neurodevelopmental/psychiatric PGS also differed: both nontypically developing classes showed elevated ADHD PGS compared to the low-stable group, and the late-emerging group additionally showed elevated schizophrenia PGS and decreased executive function PGS, whereas the declining group showed elevated broad depression PGS. CONCLUSIONS: Distinct patterns of ADHD-autism co-development are present across development in the general population, each with different characterising factors and genetic signatures as indexed by PGS.

Covid-19, social restrictions, and mental distress among young people: a UK longitudinal, population-based study.

BACKGROUND: Adolescence is a critical period for social and emotional development. We sought to examine the impacts of Covid-19 and related social restrictions and school closures on adolescent mental health, particularly among disadvantaged, marginalised, and vulnerable groups. METHODS: We analysed four waves of data - 3 pre-Covid-19 (2016-2019) and 1 mid-Covid-19 (May-Aug 2020; n, 1074; 12-18 years old, >80% minority ethnic groups, 25% free school meals) from REACH (Resilience, Ethnicity, and AdolesCent Mental Health), an adolescent cohort based in inner-London, United Kingdom. Mental health was assessed using validated measures at each time point. We estimated temporal trends in mental distress and examined variations in changes in distress, pre- to mid-Covid-19, by social group, and by pre- and mid-pandemic risks. RESULTS: We found no evidence of an overall increase in mental distress midpandemic (15.9%, 95% CI: 13.0, 19.4) compared with prepandemic (around 18%). However, there were variations in changes in mental distress by subgroups. There were modest variations by social group and by pre-Covid risks (e.g., a small increase in distress among girls (b [unstandardised beta coefficient] 0.42 [-0.19, 1.03]); a small decrease among boys (b - 0.59 [-1.37, 0.19]); p for interaction .007). The most notable variations were by midpandemic risks: that is, broadly, increases in distress among those reporting negative circumstances and impacts (e.g., in finances, housing, social support and relationships, and daily routines) and decreases in distress among those reporting positive impacts. CONCLUSIONS: We found strong evidence that mental distress increased among young people who were most negatively impacted by Covid-19 and by related social restrictions during the first lockdown in the United Kingdom.

Assessment of age-at-onset criterion for adult attention-deficit hyperactivity disorder.

To investigate the accuracy of the age-at-onset criterion in those who meet other DSM-5 criteria for attention-deficit hyperactivity disorder, using a prospective population cohort we compared four different approaches to asking those aged 25 years (n = 138) when their symptoms started. Receiver operating characteristic curves showed variation between the approaches (χ(3) = 8.99, P = 0.03); all four showed low discrimination against symptoms that had been assessed when they were children (area under the curve: 0.57-0.68). Asking adults to recall specific symptoms may be preferable to recalling at what age symptoms started. However, limitations to retrospective recall add to debate on the validity of ADHD age-at-onset assessment.

Prevalence of conduct problems and social risk factors in ethnically diverse inner-city schools.

BACKGROUND: In the UK, around 5% of 11-16-year olds experience conduct problems of clinical importance. However, there are limited data on prevalence of conduct problems by ethnic group, and how putative social risk factors may explain any variations in prevalence. This study has two main aims: (1) to estimate the prevalence and nature of conduct problems overall, and by ethnic group and gender, among adolescents in diverse inner-city London schools; (2) to assess the extent to which putative risk factors - racial discrimination, socioeconomic status, parental control, and troublesome friends - explain any observed differences in prevalence of conduct problems between ethnic groups. METHODS: This study uses baseline data from REACH, an accelerated cohort study of adolescent mental health in inner-city London. Self-report questionnaire data were collected on conduct problems and a range of distinct putative social risk factors (including racial discrimination, free school meals, troublesome friends, and parental care and control). A total of 4353 pupils, 51% girls, aged 11-14 participated. We estimated prevalence of conduct problems and used multilevel logistic regression to examine differences by ethnicity and gender and associations with putative risk factors. RESULTS: Prevalence of conduct problems in inner-city schools was around three times higher than reported in national studies (i.e., 16% [95%CI: 15·2-17·5] vs. 5% [95%CI 4·6-5·9]). Compared with overall prevalence, conduct problems were lower among Indian/Pakistani/Bangladeshi (RR: 0.53 [95% CI:0.31-0.87]) and white British (RR: 0.65 [0.51-0.82]) groups, and higher among black Caribbean (RR: 1.39 [95%CI:1.19-1.62]) and mixed white and black (RR: 1.29 [95% CI: 1.02-1.60]) groups. Risk of conduct problems was higher among those who were exposed to racial discrimination compared with those who were not (RR: 1.95 [95% CI: 1.59-2.31]). CONCLUSIONS: Conduct problems are markedly more common in inner-city schools, and variations in the prevalence of conduct problems are, to some extent, rooted in modifiable social contexts and experiences, such as experiences of racial discrimination.

Weather underground: Subsurface hydrologic processes mediate tree vulnerability to extreme climatic drought.

Drought extent and severity have increased and are predicted to continue to increase in many parts of the world. Understanding tree vulnerability to drought at both individual and species levels is key to ongoing forest management and preparation for future transitions in community composition. The influence of subsurface hydrologic processes is particularly important in water-limited ecosystems, and is an under-studied aspect of tree drought vulnerability. With California's 2013-2016 extraordinary drought as a natural experiment, we studied four co-occurring woodland tree species, blue oak (Quercus douglasii), valley oak (Quercus lobata), gray pine (Pinus sabiniana), and California juniper (Juniperus californica), examining drought vulnerability as a function of climate, lithology and hydrology using regional aerial dieback surveys and site-scale field surveys. We found that in addition to climatic drought severity (i.e., rainfall), subsurface processes explained variation in drought vulnerability within and across species at both scales. Regionally for blue oak, severity of dieback was related to the bedrock lithology, with higher mortality on igneous and metamorphic substrates, and to regional reductions in groundwater. At the site scale, access to deep subsurface water, evidenced by stem water stable isotope composition, was related to canopy condition across all species. Along hillslope gradients, channel locations supported similar environments in terms of water stress across a wide climatic gradient, indicating that subsurface hydrology mediates species' experience of drought, and that areas associated with persistent access to subsurface hydrologic resources may provide important refugia at species' xeric range edges. Despite this persistent overall influence of the subsurface environment, individual species showed markedly different response patterns. We argue that hydrologic niche segregation can be a useful lens through which to interpret these differences in vulnerability to climatic drought and climate change.

Young Adult ADHD Symptoms in the General Population and Neurocognitive Impairment.

OBJECTIVE: Neurocognitive impairments are associated with child and adult ADHD in clinical settings. However, it is unknown whether adult ADHD symptoms in the general population are associated with the same pattern of cognitive impairment. We examined this using a prospective, population-based cohort spanning birth to age 25 years. METHODS: We examined associations between self-reported adult ADHD symptoms and cognitive task performance (attention and response inhibition) in adulthood and childhood. RESULTS: Self-rated ADHD symptoms at age 25 were associated with poorer performance in age 25 cognitive tasks capturing ADHD-related functioning (attention B = -0.03, 95% CI [0.05, -0.01], p = .005; response inhibition B = -0.03, 95% CI [-0.05, -0.01], p = .002). CONCLUSIONS: Neurocognitive impairments linked to adult ADHD symptoms in the general population, are similar to those found in people with childhood ADHD symptoms and are consistent with findings in adult ADHD clinical samples.

Networks of Neurodevelopmental Traits, Socioenvironmental Factors, Emotional Dysregulation in Childhood, and Depressive Symptoms Across Development in Two U.K. Cohorts.

OBJECTIVE: Previous population-based studies have identified associations between childhood neurodevelopmental traits and depression in childhood, adolescence, and young adulthood. However, neurodevelopmental traits are highly correlated with each other, which could confound associations when traits are examined in isolation. The authors sought to identify unique associations between multiple neurodevelopmental traits in childhood and depressive symptoms across development, while taking into account co-occurring difficulties, in multivariate analyses. METHODS: Data from two U.K. population-based cohorts, the Twins Early Development Study (TEDS) (N=4,407 independent twins) and the Avon Longitudinal Study of Parents and Children (ALSPAC) (N=10,351), were independently analyzed. Bayesian Gaussian graphical models were estimated to investigate pairwise conditional associations between neurodevelopmental traits (autism and ADHD symptoms and general cognitive, learning, and communication abilities), socioenvironmental stressors (academic performance and peer relations), and emotional dysregulation in childhood (ages 7-11) and depressive symptoms across development (ages 12, 16, and 21). RESULTS: In both cohorts, bivariate correlations indicated several associations between neurodevelopmental traits and depressive symptoms across development. However, based on replicated findings across cohorts, these pairs of variables were mostly conditionally independent, and none were conditionally associated, after accounting for socioenvironmental stressors and emotional dysregulation. In turn, socioenvironmental stressors and emotional dysregulation were conditionally associated with both neurodevelopmental traits and depressive symptoms. Based on replicated findings across cohorts, neurodevelopmental traits in childhood could be associated only indirectly with depressive symptoms across development. CONCLUSIONS: This study indicates that associations between childhood neurodevelopmental traits and depressive symptoms across development could be explained by socioenvironmental stressors and emotional dysregulation. The present findings could inform future research aimed at the prevention of depression in youths with neurodevelopmental disorders.

Mental-health before and during the COVID-19 pandemic in adults with neurodevelopmental disorders.

The COVID-19 pandemic negatively impacted mental health globally. Individuals with neurodevelopmental disorders (NDDs), including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), are at elevated risk of mental health difficulties. We investigated the impact of the pandemic on anxiety, depression and mental wellbeing in adults with NDDs using data from the Avon Longitudinal Study of Parents and Children (n = 3058). Mental health data were collected pre-pandemic (age 21-25) and at three timepoints during the pandemic (ages 27-28) using the Short Mood and Feelings Questionnaire, Generalized Anxiety Disorder Assessment-7, and Warwick Edinburgh Mental Wellbeing Scale. ADHD and ASD were defined using validated cut-points of the Strengths and Difficulties Questionnaire and Autism Spectrum Quotient, self-reported at age 25. We used multi-level mixed-effects models to investigate changes in mental health in those with elevated ADHD/ASD traits compared to those without. Prevalences of depression, anxiety and poor mental wellbeing were higher at all timepoints (pre-pandemic and during pandemic) in those with ADHD and ASD compared to those without. Anxiety increased to a greater extent in those with ADHD (ß = 0.8 [0.2,1.4], p = 0.01) and ASD (ß = 1.2 [-0.1,2.5], p = 0.07), while depression symptoms decreased, particularly in females with ASD (ß = -3.1 [-4.6,-1.5], p = 0.0001). On average, mental wellbeing decreased in all, but to a lesser extent in those with ADHD (ß = 1.3 [0.2,2.5], p = 0.03) and females with ASD (ß = 3.0 [0.2,5.9], p = 0.04). To conclude, anxiety disproportionately increased in adults with NDDs during the pandemic, however, the related lockdowns may have provided a protective environment for depressive symptoms in the same individuals.

Young-Adult Social Outcomes of Attention-Deficit/Hyperactivity Disorder.

Objective: Attention-deficit/hyperactivity disorder (ADHD) is associated with a range of adverse outcomes in adult life. However, it is unclear whether the risk pathways to adverse adult outcomes are established during childhood or whether associations are driven by concurrent ADHD symptoms that have persisted to adulthood.Methods: We examined associations between broadly defined child-limited (remitted) and persistent ADHD (assessed using the ADHD subscale of the Strengths and Difficulties Questionnaire) with negative social outcomes (low emotional and instrumental support, antisocial behavior, employment, receipt of state benefits as an indicator of socio-economic disadvantage, homelessness) at age 25 years in a UK longitudinal population sample, the Avon Longitudinal Study of Parents and Children (age 25 data collected between years 2017 and 2018; total N = 6,439).Results: Up to 20% of young people with less favorable social outcomes at age 25 had persistent ADHD. Persistent ADHD was associated with an increased likelihood of being not in education, employment, or training (NEET) (OR = 3.71, 95% CI = 2.06 to 6.67, P = 1 × 10-05) and receiving state benefits (OR = 2.72, 95% CI = 1.62 to 4.57, P = 2 × 10-04) at age 25 years compared to those without ADHD. We did not find strong evidence of associations between child-limited ADHD and social outcomes (NEET OR = 1.20, 95% CI = 0.54 to 2.69, P = .65; state benefits OR = 1.38, 95% CI = 0.76 to 2.51, P = .29). Persistent ADHD associations with negative social outcomes were observed across family-of-origin income groups and sex and were not explained by comorbidity.Conclusions: Our findings highlight the importance of continued monitoring and management of ADHD symptoms and related social as well as clinical outcomes across development into adulthood. Future research is needed to identify what factors promote positive social outcomes, including effective treatment of adult ADHD symptoms.

Investigating young-adult social outcomes of attention deficit hyperactivity disorder.

Objective: Attention Deficit Hyperactivity Disorder (ADHD) is associated with a range of adverse outcomes in adult life. However it is unclear whether the risk pathways to adverse adult outcomes are established during childhood or whether associations are driven by concurrent ADHD symptoms that have persisted to adulthood. Methods: We examined associations between broadly defined child-limited (remitted) and persistent ADHD (assessed using the ADHD subscale of the Strengths and Difficulties Questionnaire) with social outcomes (low emotional and instrumental support, antisocial behaviour, employment, receipt of state benefits as an indicator of socio-economic disadvantage, homelessness) at age 25 years in a UK longitudinal population sample ALPSAC (the Avon Longitudinal Study of Parents and Children, age 25 data collected between years 2017 and 2018): total N=6439. Results: Up to 20% of young-people with less favourable social outcomes at age 25 had persistent ADHD. Persistent ADHD was associated with an increased likelihood of being not in education, employment or training (NEET: OR=3.71, 95% CI=2.06 to 6.67, p=1x10-05) and receiving state benefits (OR=2.72, 95% CI=1.62 to 4.57, p=2x10-04) at age 25 years compared to those without ADHD. We did not find strong evidence of associations between child-limited ADHD and social outcomes (NEET OR=1.20, 95% CI=0.54 to 2.69, p=0.65; state benefits OR=1.38, 95% CI=0.76 to 2.51, p=0.29). Persistent ADHD associations with negative social outcomes were observed across family-of-origin income groups, sex and were not explained by comorbidity. Conclusion: Our findings highlight the importance of continued monitoring and management of ADHD symptoms and related social as well as clinical outcomes across development into adulthood. Future research is needed to identify what factors promote positive social outcomes, including effective treatment of adult ADHD symptoms.

Cross-cohort change in parent-reported emotional problem trajectories across childhood and adolescence in the UK.

BACKGROUND: Over the past three decades, the prevalence of adolescent emotional problems (ie, anxiety and depression) has risen. Although the onset and developmental course of emotional symptoms shows high variability, no study has directly tested secular differences across development. Our aim was to investigate whether and how developmental trajectories of emotional problems have changed across generations. METHODS: We used data from two UK prospective cohorts assessed 10 years apart: the Avon Longitudinal Study of Parents and Children (ALSPAC) including individuals born in 1991-92, and the Millennium Cohort Study (MCS) with individuals born in 2000-02. Our outcome was emotional problems, assessed using the parent-rated emotional subscale of the Strengths and Difficulties Questionnaire (SDQ-E) at approximate ages 4, 7, 8, 10, 11, 13, and 17 years in ALSPAC and ages 3, 5, 7, 11, 14, and 17 years in MCS. Participants were included if the SDQ-E was completed at least once in childhood and at least once in adolescence. Trajectories were generated using multilevel growth curve models using the repeated assessments of the SDQ-E in children aged 3-17 years. FINDINGS: Data were available for 19 418 participants (7012 from ALSPAC and 12 406 from the MCS), of whom 9678 (49·8%) were female and 9740 (50·2%) were male, and 17 572 (90·5%) had White mothers. Individuals born between 2000 and 2002 had higher emotional problem scores from around 9 years (intercept statistic ß 1·75, 95% CI 1·71-1·79) than did individuals born in 1991-92 (1·55, 1·51-1·59). The later cohort had an earlier onset of problems than the earlier cohort, and sustained higher average trajectories from around 11 years, with female adolescents showing the steepest trajectories of emotional problems. Differences between cohorts peaked overall at age 14 years. INTERPRETATION: Our comparison of two cohorts of young people provides evidence that compared with a cohort assessed 10 years prior, emotional problems emerge earlier in development in the more recent cohort, and these are especially pronounced for females during mid-adolescence. Such findings have implications for public health planning and service provision. FUNDING: Wolfson Centre for Young People's Mental Health, Wolfson Foundation.

Mountain lions avoid burned areas and increase risky behavior after wildfire in a fragmented urban landscape.

Urban environments are high risk areas for large carnivores, where anthropogenic disturbances can reduce fitness and increase mortality risk.1 When catastrophic events like large wildfires occur, trade-offs between acquiring resources and avoiding risks of the urban environment are intensified. This landscape context could lead to an increase in risk-taking behavior by carnivores if burned areas do not allow them to meet their energetic needs, potentially leading to human-wildlife conflict.2,3 We studied mountain lion behavior using GPS location and accelerometer data from 17 individuals tracked before and after a large wildfire (the 2018 Woolsey Fire) within a highly urbanized area (Los Angeles, California, USA). After the wildfire, mountain lions avoided burned areas and increased behaviors associated with anthropogenic risk, including more frequent road and freeway crossings (mean crossings increased from 3 to 5 per month) and greater activity during the daytime (means from increased 10% to 16% of daytime active), a time when they are most likely to encounter humans. Mountain lions also increased their amount of space used, distance traveled (mean distances increased from 250 to 390 km per month), and intrasexual overlap, potentially putting them at risk of intraspecific conflict. Joint pressures from urbanization and severe wildfire, alongside resulting risk-taking, could thus increase mortality and extinction risk for populations already suffering from low genetic diversity, necessitating increased connectivity in fire-prone areas.

"Late-onset" ADHD symptoms in young adulthood: Is this ADHD?

Objective: We investigated whether "late-onset" ADHD that emerges in adolescence/adulthood is similar in risk factor profile to: (1) child-onset ADHD, but emerges later because of scaffolding/compensation from childhood resources; and (2) depression, because it typically onsets in adolescence/adulthood and shows symptom and genetic overlaps with ADHD. Methods: We examined associations between late-onset ADHD and ADHD risk factors, cognitive tasks, childhood resources and depression risk factors in a population-based cohort followed-up to age 25 years (N=4224-9764). Results: Parent-rated late-onset ADHD was like child-onset persistent ADHD in associations with ADHD polygenic risk scores and cognitive task performance, although self-rated late-onset ADHD was not. Late-onset ADHD was associated with higher levels of childhood resources than child-onset ADHD and did not show strong evidence of association with depression risk factors. Conclusions: Late-onset ADHD shares characteristics with child-onset ADHD when parent-rated, but differences for self-reports require investigation. Childhood resources may delay the onset of ADHD.

Decline in attention-deficit hyperactivity disorder traits over the life course in the general population: trajectories across five population birth cohorts spanning ages 3 to 45 years.

BACKGROUND: Trajectories of attention-deficit hyperactivity disorder (ADHD) traits spanning early childhood to mid-life have not been described in general populations across different geographical contexts. Population trajectories are crucial to better understanding typical developmental patterns. METHODS: We combined repeated assessments of ADHD traits from five population-based cohorts, spanning ages 3 to 45 years. We used two measures: (i) the Strengths and Difficulties Questionnaire (SDQ) hyperactive-inattentive subscale (175 831 observations, 29 519 individuals); and (ii) scores from DSM-referenced scales (118 144 observations, 28 685 individuals). Multilevel linear spline models allowed for non-linear change over time and differences between cohorts and raters (parent/teacher/self). RESULTS: Patterns of age-related change differed by measure, cohort and country: overall, SDQ scores decreased with age, most rapidly declining before age 8 years (-0.157, 95% CI: -0.170, -0.144 per year). The pattern was generally consistent using DSM scores, although with greater between-cohort variation. DSM scores decreased most rapidly between ages 14 and 17 years (-1.32%, 95% CI: -1.471, -1.170 per year). Average scores were consistently lower for females than males (SDQ: -0.818, 95% CI: -0.856, -0.780; DSM: -4.934%, 95% CI: -5.378, -4.489). This sex difference decreased over age for both measures, due to an overall steeper decrease for males. CONCLUSIONS: ADHD trait scores declined from childhood to mid-life, with marked variation between cohorts. Our results highlight the importance of taking a developmental perspective when considering typical population traits. When interpreting changes in clinical cohorts, it is important to consider the pattern of expected change within the general population, which is influenced by cultural context and measurement.

Bats partition activity in space and time in a large, heterogeneous landscape.

Diverse species assemblages theoretically partition along multiple resource axes to maintain niche separation between all species. Temporal partitioning has received less attention than spatial or dietary partitioning but may facilitate niche separation when species overlap along other resource axes. We conducted a broad-scale acoustic study of the diverse and heterogeneous Great Smoky Mountains National Park in the Appalachian Mountains. Between 2015 and 2016, we deployed acoustic bat detectors at 50 sites (for a total of 322 survey nights). We examined spatiotemporal patterns of bat activity (by phonic group: Low, Mid, and Myotis) to test the hypothesis that bats partition both space and time. Myotis and Low bats were the most spatially and temporally dissimilar, while Mid bats were more general in their resource use. Low bats were active in early successional openings or low-elevation forests, near water, and early in the evening. Mid bats were similarly active in all land cover classes, regardless of distance from water, throughout the night. Myotis avoided early successional openings and were active in forested land cover classes, near water, and throughout the night. Myotis and Mid bats did not alter their spatial activity patterns from 2015 to 2016, while Low bats did. We observed disparate temporal activity peaks between phonic groups that varied between years and by land cover class. The temporal separation between phonic groups relaxed from 2015 to 2016, possibly related to changes in the relative abundance of bats or changes in insect abundance or diversity. Temporal separation was more pronounced in the land cover classes that saw greater overall bat activity. These findings support the hypothesis that niche separation in diverse assemblages may occur along multiple resource axes and adds to the growing body of evidence that bats partition their temporal activity.