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This long-anticipated work shares the aims of its celebrated companion: namely, to provide an introduction for students and a reference for researchers to the techniques, results, and terminology of multiplicative number theory. This volume builds on the earlier one (which served as an introduction to basic, classical results) and focuses on sieve methods. This area has witnessed a number of major advances in recent years, e.g. gaps between primes, large values of Dirichlet polynomials and zero density estimates, all of which feature here. Despite the fact that the book can serve as an entry to contemporary mathematics, it remains largely self-contained, with appendices containing background or material more advanced than undergraduate mathematics. Again, exercises, of which there is a profusion, illustrate the theory or indicate ways in which it can be developed. Each chapter ends with a thorough set of references, which will be essential for all analytic number theorists.
The COVID-19 pandemic has impacted various aspects of daily life, leading to increased psychological symptoms and changes in alcohol use, yet little is known about their specific interactions, particularly early stages during the pandemic. We examined the relationship between psychological symptoms and alcohol-related behaviors associated with COVID-19, and determined whether associations shifted already early during the pandemic and whether changes in psychological symptoms from the pre- to during COVID-19 impacted changes in alcohol consumption.
Methods
Participants were young adults from a longitudinal cohort (N=435, age: 22–25) from two time points. We applied paired samples t-tests, correlation analyses, SHapley Additive exPlanations, and classification models to examine the multiple associations between psychological symptoms and alcohol use directly pre- and early during COVID-19.
Results
We found significant associations between psychological symptoms and alcohol use pre- compared to during COVID-19. Anxiety was the strongest factor influencing alcohol use pre-pandemic, depression had the greatest impact during COVID-19. Changes in anxiety from pre- to during COVID-19 were the main factor associated with an increase in alcohol use, while changes in depression appeared to be most predictive for a decrease/persistence in alcohol use.
Conclusion
These findings suggest a shift in the association between psychological symptoms and alcohol use following COVID-19, as well as a differential impact of psychological symptoms, depending on their changes related to the pandemic. Changes in anxiety may contribute to riskier alcohol use behaviors following the pandemic, while depression appears to be one of the most critical factors influencing alcohol use during such crisis situations.
We describe an outbreak of Legionnaires’ disease linked to an exclusive cold-water source in a private residential setting in Yorkshire. The cold-water source was identified following microbiological testing of clinical and environmental samples. Legionella pneumophila was only detected in the cold-water system. Three cases were identified over the course of the outbreak: two confirmed and one probable. Conditions favourable to bacterial growth included system ‘dead legs’ and significant heat transfer to the cold-water system. We describe challenges in implementing control measures at the venue and highlight the importance of using enforcement powers, where necessary, to reduce risk.
The relevance of education and outreach (E&O) activities about the Antarctic Treaty has been recognized at the Antarctic Treaty Consultative Meetings (ATCM) and at the Committee for Environmental Protection (CEP). This study examines the key topics and the target audiences detailed in papers submitted to the ATCM on E&O. Since the Antarctic Treaty entered into force in 1961, a total of 216 ATCM papers on E&O have been produced. The number of papers has increased substantially since the mid-1990s. ‘Science’ (76.9%) and ‘Wildlife/Biodiversity/Environment’ (75.5%) were the most addressed topics in these papers, while the ‘Public’ (81.0%) and those attending ‘Schools’ (69.0%) are the main target audiences. ‘Science’ in ATCM papers increased ~120-fold from 1961–1997 to 2015–2023, while ATCM papers discussing engagement with the ‘Public’ increased ~40-fold during the same period. ‘Climate change’ was first mentioned in 2006, and the number of papers per year increased fourfold by 2015–2023. This study shows the increasing interest in E&O through time, addressing key topics to relevant audiences related to the Antarctic region. From an educational perspective, attention should be paid to emerging topics (e.g. equity, diversity and inclusion), and the engagement of early-career professionals and educators should be made a priority.
The increased severity and frequency of bushfires accompanying human-induced global warming have dire implications for biodiversity conservation. Here we investigate the response of a cryptic, cool-climate elapid, the mustard-bellied snake Drysdalia rhodogaster, to the extensive Black Summer fires of 2019/2020 in south-eastern Australia. The species is categorized as Least Concern on the IUCN Red List (last assessed in 2017), but because a large part of its range was burnt during the Black Summer and little was known about its ecology, D. rhodogaster was identified as a priority species for post-fire impact assessment. We evaluated three lines of evidence to assess the impact of the Black Summer fires on D. rhodogaster. Habitat suitability modelling indicated that c. 46% of the predicted range of the species was affected by bushfire. Field surveys conducted 9–36 months post-fire and collation of records from public databases submitted 0–24 months post-fire indicated that D. rhodogaster persisted in burnt landscapes. Fire severity and proportion of the landscape that was burnt within a 1,000-m radius of survey sites were poor predictors of site occupancy by D. rhodogaster. Although conclusions regarding the effects of fire on D. rhodogaster are limited because of the lack of baseline data, it is evident that the species has persisted across the landscape in the wake of extensive bushfires. Our work highlights the need for baseline knowledge on cryptic species even when they are categorized as Least Concern, as otherwise assessments of the impacts of catastrophic events will be constrained.
Psychotic symptoms in adolescence are associated with social adversity and genetic risk for schizophrenia. This gene–environment interplay may be mediated by personality, which also develops during adolescence. We hypothesized that (i) personality development predicts later Psychosis Proneness Signs (PPS), and (ii) personality traits mediate the association between genetic risk for schizophrenia, social adversities, and psychosis.
Methods
A total of 784 individuals were selected within the IMAGEN cohort (Discovery Sample-DS: 526; Validation Sample-VS: 258); personality was assessed at baseline (13–15 years), follow-up-1 (FU1, 16–17 years), and FU2 (18–20 years). Latent growth curve models served to compute coefficients of individual change across 14 personality variables. A support vector machine algorithm employed these coefficients to predict PPS at FU3 (21–24 years). We computed mediation analyses, including personality-based predictions and self-reported bullying victimization as serial mediators along the pathway between polygenic risk score (PRS) for schizophrenia and FU3 PPS. We replicated the main findings also on 1132 adolescents recruited within the TRAILS cohort.
Results
Growth scores in neuroticism and openness predicted PPS with 65.6% balanced accuracy in the DS, and 69.5% in the VS Mediations revealed a significant positive direct effect of PRS on PPS (confidence interval [CI] 0.01–0.15), and an indirect effect, serially mediated by personality-based predictions and victimization (CI 0.006–0.01), replicated in the TRAILS cohort (CI 0.0004–0.004).
Conclusions
Adolescent personality changes may predate future experiences associated with psychosis susceptibility. PPS personality-based predictions mediate the relationship between PRS and victimization toward adult PPS, suggesting that gene–environment correlations proposed for psychosis are partly mediated by personality.
In July 2021, Public Health Wales received two notifications of salmonella gastroenteritis. Both cases has attended the same barbecue to celebrate Eid al–Adha, two days earlier. Additional cases attending the same barbecue were found and an outbreak investigation was initiated. The barbecue was attended by a North African community’s social network. On same day, smaller lunches were held in three homes in the social network. Many people attended both a lunch and the barbecue. Cases were defined as someone with an epidemiological link to the barbecue and/or lunches with diarrhoea and/or vomiting with date of onset following these events. We undertook a cohort study of 36 people attending the barbecue and/or lunch, and a nested case-control study using Firth logistic regression. A communication campaign, sensitive towards different cultural practices, was developed in collaboration with the affected community. Consumption of a traditional raw liver dish, ‘marrara’, at the barbecue was the likely vehicle for infection (Firth logistic regression, aOR: 49.99, 95%CI 1.71–1461.54, p = 0.02). Meat and offal came from two local butchers (same supplier) and samples yielded identical whole genome sequences as cases. Future outbreak investigations should be relevant to the community affected by considering dishes beyond those found in routine questionnaires.
Identifying youths most at risk to COVID-19-related mental illness is essential for the development of effective targeted interventions.
Aims
To compare trajectories of mental health throughout the pandemic in youth with and without prior mental illness and identify those most at risk of COVID-19-related mental illness.
Method
Data were collected from individuals aged 18–26 years (N = 669) from two existing cohorts: IMAGEN, a population-based cohort; and ESTRA/STRATIFY, clinical cohorts of individuals with pre-existing diagnoses of mental disorders. Repeated COVID-19 surveys and standardised mental health assessments were used to compare trajectories of mental health symptoms from before the pandemic through to the second lockdown.
Results
Mental health trajectories differed significantly between cohorts. In the population cohort, depression and eating disorder symptoms increased by 33.9% (95% CI 31.78–36.57) and 15.6% (95% CI 15.39–15.68) during the pandemic, respectively. By contrast, these remained high over time in the clinical cohort. Conversely, trajectories of alcohol misuse were similar in both cohorts, decreasing continuously (a 15.2% decrease) during the pandemic. Pre-pandemic symptom severity predicted the observed mental health trajectories in the population cohort. Surprisingly, being relatively healthy predicted increases in depression and eating disorder symptoms and in body mass index. By contrast, those initially at higher risk for depression or eating disorders reported a lasting decrease.
Conclusions
Healthier young people may be at greater risk of developing depressive or eating disorder symptoms during the COVID-19 pandemic. Targeted mental health interventions considering prior diagnostic risk may be warranted to help young people cope with the challenges of psychosocial stress and reduce the associated healthcare burden.
A major consideration for maritime activity in the Southern Hemisphere is the northern limit of icebergs, or the Southern Ocean Limit Of Known Ice (SOLOKI). This analysis of historical reports of icebergs during Southern Hemisphere voyages from 1687 to 1933 provides a basis for examination of their geographical and chronological occurrence during ~250 years. The analyses use tabulated data from 742 voyages and other reports from many sources, some including first-person descriptions. While these data are dependent on icebergs being reported by mariners, as well as the variable frequency of voyages, they demonstrate distinct periods of exceptional frequency of icebergs occurring in certain localities, particularly the far South Atlantic. Based upon historical records the evidence suggests unprecedented numbers of icebergs were present in southern shipping channels in the 1890s. When these historical observations are combined with modern iceberg drift trajectories, their possible origin can be elucidated. Owing to the numbers of icebergs seen and their geographical spread, our results suggest that this was possibly the largest near-synchronous calvings in the last 300 years, and the northernmost extent of the SOLOKI.
We recently reported on the radio-frequency attenuation length of cold polar ice at Summit Station, Greenland, based on bi-static radar measurements of radio-frequency bedrock echo strengths taken during the summer of 2021. Those data also allow studies of (a) the relative contributions of coherent (such as discrete internal conducting layers with sub-centimeter transverse scale) vs incoherent (e.g. bulk volumetric) scattering, (b) the magnitude of internal layer reflection coefficients, (c) limits on signal propagation velocity asymmetries (‘birefringence’) and (d) limits on signal dispersion in-ice over a bandwidth of ~100 MHz. We find that (1) attenuation lengths approach 1 km in our band, (2) after averaging 10 000 echo triggers, reflected signals observable over the thermal floor (to depths of ~1500 m) are consistent with being entirely coherent, (3) internal layer reflectivities are ≈–60$\to$–70 dB, (4) birefringent effects for vertically propagating signals are smaller by an order of magnitude relative to South Pole and (5) within our experimental limits, glacial ice is non-dispersive over the frequency band relevant for neutrino detection experiments.
Experiencing mental health stigma during adolescence can exacerbate mental health conditions, reduce quality of life and inhibit young people’s help-seeking for their mental health needs. For young people, education and contact have most often been viewed as suitable approaches for stigma reduction. However, evidence on the effectiveness of these anti-stigma interventions has not been consistent. This systematic review evaluated the effectiveness of interventions to reduce mental health stigma among youth aged 10–19 years. The review followed Cochrane and PRISMA guidelines. Eight databases were searched: PubMed, PsycINFO, MEDLINE, Web of Science, Scopus, EMBASE, British Education Index and CNKI. Hand searching from included studies was also conducted. Randomised controlled trials and experimental designs that included randomised allocation to interventions and control groups were included in the review. Narrative synthesis was employed to analyse the results. A meta-analysis was conducted to determine the effectiveness of included interventions. Twenty-two studies were included in the review. Eight studies reported positive effects, 11 studies found mixed effects and 3 studies reported no effect on indicators of mental health stigma among youth. Seven of the effective studies were education-based. Eleven studies were suitable for meta-analysis, and the multivariate meta-analytic model indicated a small, significant effect at post-intervention (d = .21, p < .001), but not at follow-up (d = .069, p = .347). Interventions to reduce stigma associated with mental health conditions showed small, short-term effects in young people. Education-based interventions showed relatively more significant effects than other types of interventions.
Two specimens of Metaconularia manni (Roy, 1935) from the lower Middle Silurian Scotch Grove Formation (eastern Iowa) exhibit well-defined, relict soft parts replicated in silica. One of these specimens bears phosphatic periderm, whereas the other specimen is a mold. Present within the erect, undistorted apical region of the specimen preserving periderm, on opposite sides of the peridermal cavity, are two small, elongate masses of silica located near the midlines of two of the four faces. Present in the central portion of the other specimen, at a somewhat greater distance from the apex, are five pairs of hollow, elongate, keeled pouch-like bodies (hereafter pouches), the long axes of which converge on the center of the fossil. Each pair of pouches is associated with a short, narrow, gently curved or broadly U-shaped tube, also composed of silica. Additionally, two of the pouch/tube combinations are associated with a pair of rectilinear furrows that correspond to the paired internal carinae that straddled the conulariid's facial midlines. We interpret the paired pouches and short tubes in the moldic specimen as relic conulariid soft parts homologous, respectively, to the interradial gonads and retractor muscles of extant, stauromedusan and polypoid scyphozoan cnidarians. Unlike most conulariids, which exhibit four faces, this individual had five faces, an aberrant morphology known in one other conulariid. The two small masses in the other specimen are more difficult to interpret, but they, too, could be relic gonads or longitudinal muscles. These interpretations suggest that, as in certain extant scyphozoans, at least one conulariid lost the free-living, sexual medusoid life phase.
Many business transactions and employment contracts are wrongfully exploitative despite being consensual and beneficial to both parties, compared with a nontransaction baseline. This form of exploitation can present governments with a dilemma. Legally permitting exploitation may send the message that the public condones it. In some economic conditions, coercively enforced antiexploitation law may harm the people it is intended to help. Under these conditions, a way out of the dilemma is to enact laws with provisions that lack coercive enforcement. Noncoercive law would convey the state’s condemnation of wrongful exploitation without risking the harmful effects of coercively enforced law. It would also give firms and their agents a way of explaining nonexploitative pricing decisions to investors, and it may help give precise content to the moral duty to set prices and wages fairly. Governments should thus consider noncoercive law a viable component of their responses to exploitation.
Refractory depression is a devastating condition with significant morbidity, mortality, and societal cost. Approximately 15% of patients with major depressive disorder are refractory to currently available treatments. We hypothesized metabolic abnormalities contributing to treatment refractory depression are associated with distinct findings identifiable in the cerebrospinal fluid (CSF). Our hypothesis was confirmed by a previous small case-controlled study. Here we present a second, larger replication study.
Methods
We conducted a case-controlled, targeted, metabolomic evaluation of 141 adolescent and adult patients with well-characterized history of depression refractory to three maximum-dose, adequate-duration medication treatments, and 36 healthy controls. Plasma, urine, and CSF metabolic profiling were performed by coupled gas chromatography/mass spectrometry, and high-performance liquid chromatography, electrospray ionization, tandem mass spectrometry.
Results
Abnormalities were identified in 67 of 141 treatment refractory depression participants. The CSF abnormalities included: low cerebral folate (n = 20), low tetrahydrobiopterin intermediates (n = 11), and borderline low-tetrahydrobiopterin intermediates (n = 20). Serum abnormalities included abnormal acylcarnitine profile (n = 12) and abnormal serum amino acids (n = 20). Eighteen patients presented with two or more abnormal metabolic findings. Sixteen patients with cerebral folate deficiency and seven with low tetrahydrobiopterin intermediates in CSF showed improvement in depression symptom inventories after treatment with folinic acid and sapropterin, respectively. No healthy controls had a metabolite abnormality.
Conclusions
Examination of metabolic disorders in treatment refractory depression identified an unexpectedly large proportion of patients with potentially treatable abnormalities. The etiology of these abnormalities and their potential roles in pathogenesis remain to be determined.
Experiential learning, such as simulation-based training, is widely used in health education. Dramatic self-expression adds another layer through enacted perspective taking, and embodied self-exploration of interaction with others, to foster situated learning. We describe the evaluation of an innovative drama-based experiential learning project involving collaboration between multidisciplinary mental healthcare staff and people with lived experience of mental illness. The programme was facilitated at East London NHS Foundation Trust by a theatre company experienced in delivering workshops with service users. A weekly group programme took place online over 8 weeks during the COVID-19 pandemic and included activities of improvisation, embodied enactments and debriefing. The programme led to co-production of a drama piece that was filmed and distributed online. It was hypothesised that the experiential learning might result in individual benefits for all participants, such as improved well-being and increased mutual understanding of each other's experience of mental health care. The project aimed to improve relationships between healthcare disciplines, and between staff and service users. Additionally, aims were to empower service users, and support staff to practice core interpersonal skills. Objectives of the evaluation were to study the impact of the experiential learning, understand participants’ experience, and explore challenges and benefits.
Methods
A mixed methods approach was taken to evaluate the programme. Following completion of the project, participants were invited to complete a questionnaire utilising a Likert scale rating of overall satisfaction with the project, perceived benefit and impact on specific domains such as working with others. One-to-one semi-structured interviews were conducted according to a topic-guide, and qualitative data were analysed using open & axial coding for thematic analysis.
Results
11 participants, including Psychiatrists, Occupational Therapists and current service users, completed the experiential learning and filming. Questionnaire data suggested participants were highly satisfied with the learning and felt it would be valuable to others. Themes include the positive experience of creativity, dismantling of hierarchy, improved empathy, confidence and connection. Potential challenges were digital inequality and lack of dedicated time for professional development.
Conclusion
A drama-based experiential learning group programme for healthcare staff and service users is a highly beneficial learning experience. Participants describe changes on a personal level as well as improved understanding of others’ perspectives. This form of experiential learning features collaborative working that aligns with principles of co-production and supports the development of interpersonal skills; the findings suggest that drama-based experiential learning is a useful method in health education to complement knowledge acquisition.
There are many structural problems facing the UK at present, from a weakened National Health Service to deeply ingrained inequality. These challenges extend through society to clinical practice and have an impact on current mental health research, which was in a perilous state even before the coronavirus pandemic hit. In this editorial, a group of psychiatric researchers who currently sit on the Academic Faculty of the Royal College of Psychiatrists and represent the breadth of research in mental health from across the UK discuss the challenges faced in academic mental health research. They reflect on the need for additional investment in the specialty and ask whether this is a turning point for the future of mental health research.
It has not yet been determined if the commonly reported cannabis–psychosis association is limited to individuals with pre-existing genetic risk for psychotic disorders.
Methods
We examined whether the relationship between polygenic risk score for schizophrenia (PRS-Sz) and psychotic-like experiences (PLEs), as measured by the Community Assessment of Psychic Experiences-42 (CAPE-42) questionnaire, is mediated or moderated by lifetime cannabis use at 16 years of age in 1740 of the individuals of the European IMAGEN cohort. Secondary analysis examined the relationships between lifetime cannabis use, PRS-Sz and the various sub-scales of the CAPE-42. Sensitivity analyses including covariates, including a PRS for cannabis use, were conducted and results were replicated using data from 1223 individuals in the Dutch Utrecht cannabis cohort.
Results
PRS-Sz significantly predicted cannabis use (p = 0.027) and PLE (p = 0.004) in the IMAGEN cohort. In the full model, considering PRS-Sz and covariates, cannabis use was also significantly associated with PLE in IMAGEN (p = 0.007). Results remained consistent in the Utrecht cohort and through sensitivity analyses. Nevertheless, there was no evidence of a mediation or moderation effects.
Conclusions
These results suggest that cannabis use remains a risk factor for PLEs, over and above genetic vulnerability for schizophrenia. This research does not support the notion that the cannabis–psychosis link is limited to individuals who are genetically predisposed to psychosis and suggests a need for research focusing on cannabis-related processes in psychosis that cannot be explained by genetic vulnerability.
The number of people over the age of 65 attending Emergency Departments (ED) in the United Kingdom (UK) is increasing. Those who attend with a mental health related problem may be referred to liaison psychiatry for assessment. Improving responsiveness and integration of liaison psychiatry in general hospital settings is a national priority. To do this psychiatry teams must be adequately resourced and organised. However, it is unknown how trends in the number of referrals of older people to liaison psychiatry teams by EDs are changing, making this difficult.
Method
We performed a national multi-centre retrospective service evaluation, analysing existing psychiatry referral data from EDs of people over 65. Sites were selected from a convenience sample of older peoples liaison psychiatry departments. Departments from all regions of the UK were invited to participate via the RCPsych liaison and older peoples faculty email distribution lists. From departments who returned data, we combined the date and described trends in the number and rate of referrals over a 7 year period.
Result
Referral data from up to 28 EDs across England and Scotland over a 7 year period were analysed (n = 18828 referrals). There is a general trend towards increasing numbers of older people referred to liaison psychiatry year on year. Rates rose year on year from 1.4 referrals per 1000 ED attenders (>65 years) in 2011 to 4.5 in 2019 . There is inter and intra site variability in referral numbers per 1000 ED attendances between different departments, ranging from 0.1 - 24.3.
Conclusion
To plan an effective healthcare system we need to understand the population it serves, and have appropriate structures and processes within it. The overarching message of this study is clear; older peoples mental health emergencies presenting in ED are common and appear to be increasingly so. Without appropriate investment either in EDs or community mental health services, this is unlikely to improve.
The data also suggest very variable inter-departmental referral rates. It is not possible to establish why rates from one department to another are so different, or whether outcomes for the population they serve are better or worse. The data does however highlight the importance of asking further questions about why the departments are different, and what impact that has on the patients they serve.
What is classical music? This book answers the question in a manner never before attempted, by presenting the history of fifteen parallel traditions, of which Western classical music is just one. Eachmusic is analysed in terms of its modes, scales, and theory; its instruments, forms, and aesthetic goals; its historical development, golden age, and condition today; and the conventions governing its performance. The writers are leading ethnomusicologists, and their approach is based on the belief that music is best understood in the context of the culture which gave rise to it . By including Mande and Uzbek-Tajik music - plus North American jazz - in addition to the better-known styles of the Middle East, the Indian sub-continent, the Far East, and South-East Asia, this book offers challenging new perspectives on the word 'classical'. It shows the extent to which most classical traditions are underpinned by improvisation, and reveals the cognate origins of seemingly unrelated musics; it reflects the multifarious ways in which colonialism, migration, and new technology have affected musical development, and continue to do today. With specialist language kept to a minimum, it's designed to help both students and general readers to appreciate musical traditions which may be unfamiliar to them, and to encounter the reality which lies behind that lazy adjective 'exotic'.
MICHAEL CHURCH has spent much of his career in newspapers as a literary and arts editor; since 2010 he has been the music and opera critic of The Independent. From 1992 to 2005 he reported on traditional musics all over the world for the BBC World Service; in 2004, Topic Records released a CD of his Kazakh field recordings and, in 2007, two further CDs of his recordings in Georgia and Chechnya.
Contributors: Michael Church, Scott DeVeaux, Ivan Hewett, David W. Hughes, Jonathan Katz, Roderic Knight, Frank Kouwenhoven, Robert Labaree, Scott Marcus, Terry E. Miller, Dwight F.Reynolds, Neil Sorrell, Will Sumits, Richard Widdess, Ameneh Youssefzadeh
Sex-related differences in psychopathology are known phenomena, with externalizing and internalizing symptoms typically more common in boys and girls, respectively. However, the neural correlates of these sex-by-psychopathology interactions are underinvestigated, particularly in adolescence.
Methods
Participants were 14 years of age and part of the IMAGEN study, a large (N = 1526) community-based sample. To test for sex-by-psychopathology interactions in structural grey matter volume (GMV), we used whole-brain, voxel-wise neuroimaging analyses based on robust non-parametric methods. Psychopathological symptom data were derived from the Strengths and Difficulties Questionnaire (SDQ).
Results
We found a sex-by-hyperactivity/inattention interaction in four brain clusters: right temporoparietal-opercular region (p < 0.01, Cohen's d = −0.24), bilateral anterior and mid-cingulum (p < 0.05, Cohen's d = −0.18), right cerebellum and fusiform (p < 0.05, Cohen's d = −0.20) and left frontal superior and middle gyri (p < 0.05, Cohen's d = −0.26). Higher symptoms of hyperactivity/inattention were associated with lower GMV in all four brain clusters in boys, and with higher GMV in the temporoparietal-opercular and cerebellar-fusiform clusters in girls.
Conclusions
Using a large, sex-balanced and community-based sample, our study lends support to the idea that externalizing symptoms of hyperactivity/inattention may be associated with different neural structures in male and female adolescents. The brain regions we report have been associated with a myriad of important cognitive functions, in particular, attention, cognitive and motor control, and timing, that are potentially relevant to understand the behavioural manifestations of hyperactive and inattentive symptoms. This study highlights the importance of considering sex in our efforts to uncover mechanisms underlying psychopathology during adolescence.