Bone flap infections after craniotomy: a review of 63 cases and the implications for definitions, classification and surveillance methodologies.

BACKGROUND: Bone flap infections (BFIs) occur following neurosurgical procedures such as craniotomies. However, they are poorly defined and often not clearly differentiated from other surgical site infection in neurosurgery. AIM: To review data from a national adult neurosurgical centre to explore some clinical aspects to better inform definitions, classification and surveillance methodologies. METHODS: We retrospectively reviewed data on clinical samples sent for culture from patients with suspected BFI. We also accessed information recorded prospectively from national and local databases for evidence of BFI or related conditions based on terms used in surgical operative notes or discharge summaries and documented monomicrobial and polymicrobial infections related to craniotomy sites. FINDINGS: Between January 2016 and December 2020, we documented 63 patients with a mean age of 45 years (16-80). Craniectomy for infection of the skull was the most common terminology used to describe BFI in the coding used in a national database, 40/63 (63%), but other terms were used. A malignant neoplasm was the most common underlying condition necessitating craniectomy in 28/63 (44%) cases. Specimens submitted for microbiological investigation included 48/63 (76%) bone flaps, 38/63 (60%) fluid/pus, and 29/63 (46%) tissue. Fifty-eight (92%) patients had at least one culture-positive specimen; 32 (55%) were monomicrobial and 26 (45%) were polymicrobial. Gram-positive bacteria predominated and Staphylococcus aureus was the most common. CONCLUSION: Greater clarity on how to define BFI is required to enable better classification and the carrying out of appropriate surveillance. This will inform preventative strategies and more effective patient management.

A decade of Clostridioides difficile infection: a constant challenge to maintain the status quo.

INTRODUCTION: Clostridioides difficile infection (CDI) is a leading cause of healthcare-associated (HA) diarrhoea. We retrospectively investigated data from a comprehensive, multidisciplinary C. difficile surveillance programme focusing on hospitalized patients in a tertiary Irish hospital over 10 years. METHODS: Data from 2012 to 2021 were extracted from a centralized database, including patient demographics, admission, case and outbreak details, ribotypes (RTs), and (since 2016) antimicrobial exposures and CDI treatments. Counts of CDI by origin of infection were explored using ꭓ2 analyses, Poisson regression was used to investigate trends in rates of CDI and possible risk factors. Time to recurrent CDI was examined by a Cox proportional hazards regression. RESULTS: Over 10 years, 954 CDI patients had a 9% recurrent CDI rate. CDI testing requests occurred in only 22% of patients. Most CDIs were HA (82.2%) and affected females (odds ratio: 2.3, P<0.01). Fidaxomicin significantly reduced the hazard ratio of time to recurrent CDI. No trends in HA-CDI incidence were observed despite key time-point events and increasing hospital activity. In 2021, community-associated (CA)-CDI increased. RTs did not differ for HA versus CA for the most common RTs (014, 078, 005 and 015). Average length-of-stay differed significantly between HA (67.1 days) and CA (14.6 days) CDI. CONCLUSION: HA-CDI rates remained unchanged despite key events and increased hospital activity, whereas by 2021, CA-CDI was at its highest in a decade. The convergence of CA and HA RTs, and the proportion of CA-CDI, question the relevance of current case definitions when increasingly patients receive hospital care without an overnight hospital stay.

Is Difficulty Mostly About Impossibility? What Difficulty Implies May Be Culturally Variant.

Difficulty can signal low odds (impossibility) and high value (importance). We build on culture-as-situated cognition theory's description of culture-based fluency and disfluency to predict that the culturally fluent meaning of difficulty is culture-bound. For Americans, the culturally fluent understanding of ability is success-with-ease-not-effort, hence difficulty implies low odds of ability. This may disadvantage American institutions and practices-learning requires gaining competence and proficiency through effortful engagement. Indeed, Americans (Studies 1, 3-8; N = 4,141; Study 2, the corpus of English language) associate difficulty with impossibility more than importance. This tendency is not universal. Indian and Chinese cultures imply that difficulty can equally signal low odds and value. Indeed, people from India and China (Studies 9-11, N = 762) are as likely to understand difficulty as being about both. Effects are culture-based; how much people endorse difficulty-as-importance and difficulty-as-impossibility in their own lives did not affect results.

Apt and actionable possible identities matter: The case of academic outcomes.

INTRODUCTION: We review the longitudinal evidence documenting that middle and high school students with school-focused possible future identities subsequently attain better school outcomes. Consistent results across operationalizations of possible identities and academic outcomes imply that results are robust. However, variability in study designs means that the existing literature cannot explain the process from possible identity to academic outcomes. We draw on identity-based motivation theory to address this gap. We predict that imagining a possible school-focused future drives school engagement to the extent that students repeatedly experience their school-focused future identities as apt (relevant) and actionable (linked to strategies they can use now). METHODS: We operationalize aptness as having pairs of positive and negative school-focused possible identities (balance) and actionability as having a roadmap of concrete, linked strategies for school-focused possible selves (plausibility). We use machine learning to capture features of possible identities that predict academic outcomes and network analyses to examine these features (training sample USA 47% female, Mage = 14, N1 = 602, N2 = 540. Test sample USA 55% female, Mage = 13, N = 247). RESULTS: We report regression analyses showing that balance, plausibility, and our machine algorithm predict better end-of-school-year grades (grade point average). We use network analysis to show that our machine algorithm is associated with structural features of possible identities and balance and plausibility scores. CONCLUSIONS: Our results support the inference that student academic outcomes are improved when students experience their school-focused possible identities as apt and actionable.

Psychological distress among healthcare workers post COVID-19 pandemic: from the resilience of individuals to healthcare systems.

Since the emergence of the COVID-19 pandemic, there has been increased interest in identifying ways of protecting the mental well-being of healthcare workers (HCWs). Much of this has been directed towards promoting and enhancing the resilience of those deemed as frontline workers. Based on a review of the extant literature, this paper seeks to problematise aspects of how 'frontline work' and 'resilience' are currently conceptualised. Firstly, frontline work is arbitrarily defined and often narrowly focused on acute, hospital-based settings, leading to the needs of HCWs in other sectors of the healthcare system being overlooked. Secondly, dominant narratives are often underpinned by a reductionist understanding of the concept of resilience, whereby solutions are built around addressing the perceived deficiencies of (frontline) HCWs rather than the structural antecedents of distress. The paper concludes by considering what interventions are appropriate to minimise the risk of burnout across all sectors of the healthcare system in a post-pandemic environment.

Confirmed archaeological evidence of water deer in Vietnam: relics of the Pleistocene or a shifting baseline?

Studies of archaeological and palaeontological bone assemblages increasingly show that the historical distributions of many mammal species are unrepresentative of their longer-term geographical ranges in the Quaternary. Consequently, the geographical and ecological scope of potential conservation efforts may be inappropriately narrow. Here, we consider a case-in-point, the water deer Hydropotes inermis, which has historical native distributions in eastern China and the Korean peninsula. We present morphological and metric criteria for the taxonomic diagnosis of mandibles and maxillary canine fragments from Hang Thung Binh 1 cave in Tràng An World Heritage Site, which confirm the prehistoric presence of water deer in Vietnam. Dated to between 13 000 and 16 000 years before the present, the specimens are further evidence of a wider Quaternary distribution for these Vulnerable cervids, are valuable additions to a sparse Pleistocene fossil record and confirm water deer as a component of the Upper Pleistocene fauna of northern Vietnam. Palaeoenvironmental proxies suggest that the Tràng An water deer occupied cooler, but not necessarily drier, conditions than today. We consider if the specimens represent extirpated Pleistocene populations or indicate a previously unrecognized, longer-standing southerly distribution with possible implications for the conservation of the species in the future.

Estimated Weight of Paediatric Patients versus Measured Weight ­ A Prospective Comparison

Introduction Weight measurement is fundamental in the management of paediatric patients. Many methods have been described for estimating a patient's weight. The aim of this study was to assess the accuracy of the APLS 2017 estimated weight guidelines. Methods 100 patient charts were analysed in University Hospital Limerick's Paediatric unit. Measured weights were recorded, and estimated weights were calculated using the APLS 2017 charts. Estimated and measured weight was compared using Bland Altman plots. Results Of 100 subjects, 53 (53%) were female and 47 (47%) male. Fifty subjects (50%) were Pre-School, 32 (32%) Primary School and 18 (18%) Secondary School. Estimated weight was a good predictor for measured weight, however weight was underestimated by between 2.34% and 16.39% of measured weight. Discussion The current APLS guidelines are reasonably accurate; but accuracy decreases with increasing age. Estimation cannot replace an accurate measurement, which is not always feasible in the acute setting.

An 11 000-year-old giant muntjac subfossil from Northern Vietnam: implications for past and present populations.

Described at the end of the twentieth century, the large-antlered or giant muntjac, Muntiacus gigas (syn. vuquangensis), is a Critically Endangered species currently restricted to the Annamite region in Southeast Asia. Here we report subfossil evidence of giant muntjac, a mandible fragment dated between 11.1 and 11.4 thousand years before present, from northern Vietnam. We describe morphological and metric criteria for diagnosis and consider the specimen in the context of regional archaeological and palaeontological records of Muntiacus. We then consider the palaeoenvironmental context of the specimen and the implications for habitat requirements for extant populations. The new specimen extends the known spatial and temporal range of giant muntjacs in Vietnam and is further evidence that this species was more widely distributed in the Holocene than current records indicate. While regional proxy evidence indicates a drier climate and more open woodland habitats at the onset of the Holocene, contextual evidence indicates that the specimen derived from an animal inhabiting limestone karst forest. This record also supports the assertion that remnant populations are in a refugial state, as a result of anthropogenic pressures, rather than representing a centre of endemism. These facts underscore the urgent need for the conservation of remaining populations.

The potential contribution of 16S ribosomal RNA polymerase chain reaction to antimicrobial stewardship in culture-negative infection.

Empiric broad-spectrum antimicrobial therapy frequently results in culture-negative specimens making rationalization of therapy difficult. We retrospectively reviewed 16S rRNA polymerase chain reaction (PCR) results from 78 specimens in 60 patients. 16S rRNA was detected in 28 (47%) patients with de-escalation of therapy in five (21%). Microbial DNA was not detected in 32 (53%) patients with antimicrobials discontinued in two (8%). Neurosurgical patients had a higher proportion of positive results (53% vs 34%) and treatment rationalizations (17% vs 12%). In specific patient groups, 16s rRNA PCR is a useful antimicrobial stewardship tool for targeting antimicrobial therapy.

Hospital Resource Utilisation by Patients with Community-Acquired Pneumonia.

Little data is available on the resource utilisation of patients admitted with Community-Acquired Pneumonia (CAP) in Ireland. A retrospective review of 50 randomly-selected patients admitted to Beaumont Hospital with CAP was undertaken. The mean length of stay of patients with CAP was 12 days (+/- 16 days). All patients were emergency admissions, all had a chest x-ray, a C-reactive protein blood test, and occupied a public bed at some point during admission. Common antimicrobial therapies were intravenous (IV) amoxicillin/clavulanic acid and oral clarithromycin; 60% received physiotherapy. The estimated mean cost of CAP per patient was €14,802.17. Costs arising from admission to hospital with CAP are substantial, but efforts can be undertaken to ensure that resources are used efficiently to improve patient care such as discharge planning and fewer in-hospital ward transfers.

Atresia Hymenalis with Haematometrocolpos: A Benefit of Teaching a Case Series and Review of the Literature.

We present four cases of atresia hymenalis with resultant haematometrocolpos diagnosed in quick succession in the emergency department with a literature review.

Social class and identity-based motivation.

Attainments often fall short of aspirations to lead lives of meaning, health, happiness and success. Identity-based motivation theory highlights how social class and cultural contexts affect likelihood of shortfalls: Identities influence the strategies people are willing to use to attain their goals and the meaning people make of experienced ease and difficulty. Though sensitive to experienced ease and difficulty, people are not sensitive to the sources of these experiences. Instead, people make culturally-tuned inferences about what their experiences imply for who they are and could become and what to do about it. American culture highlights personal and shadows structural causes of ease and difficulty, success and failure. As a result, people infer that class-based outcomes are deserved reflections of character.

Under-diagnosis of mood disorders in Canada.

AIMS: Under-diagnosis of mood disorders occurs worldwide. In this study, we characterized and compared Canadians with symptoms compatible with a mood disorder by diagnosis status; and described the associated health impacts, use of health services and perceived need for care. METHODS: Respondents to the 2012 Canadian Community Health Survey - Mental Health, a nationally representative sample of Canadians age ≥15 years were assessed for symptoms compatible with mood disorders based on a Canadian adaptation of the World Health Organization Composite International Diagnostic Interview (n = 23 504). Descriptive and multivariate regression analyses were performed. RESULTS: In 2012, an estimated 5.4% (1.5 million) Canadians aged 15 years and older reported symptoms compatible with a mood disorder, of which only half reported having been professionally diagnosed. The undiagnosed individuals were more likely to be younger (mean age: 36.2 v. 41.8), to be single (49.5 v. 32.7%), to have less than a post-secondary graduation (49.8 v. 41.1%) and to have no physical co-morbidities (56.4 v. 35.7%), and less likely to be part of the two lower income quintiles (49.6 v. 62.7%) compared with those with a previous diagnosis. Upon controlling for all socio-demographic and health characteristics, the associations with age and marital status disappeared. While those with a previous diagnosis reported significantly greater health impacts and were more likely to have consulted a health professional for their emotional and mental health problems in the previous 12 months compared with those undiagnosed (79.4 v. 31.0%), about a third of both groups reported that their health care needs were only partially met or not met at all. CONCLUSIONS: Mood disorders are prevalent and can profoundly impact the life of those affected, however, their diagnosis remains suboptimal and health care use falls short of apparent needs. Improvements in mental health literacy, help-seeking behaviours and diagnosis are needed. In light of the heterogeneity of mood disorders in terms of symptoms severity, impacts and prognosis, interventions must be tailored accordingly.

The 2014 Survey on Living with Chronic Diseases in Canada on Mood and Anxiety Disorders: a methodological overview. / Enquête sur les personnes ayant une maladie chronique au Canada ­ Composante des troubles de l'humeur et d'anxiété, 2014 : aperçu de la méthodologie.

INTRODUCTION: There is a paucity of information about the impact of mood and anxiety disorders on Canadians and the approaches used to manage them. To address this gap, the 2014 Survey on Living with Chronic Diseases in Canada-Mood and Anxiety Disorders Component (SLCDC-MA) was developed. The purpose of this paper is to describe the methodology of the 2014 SLCDC-MA and examine the sociodemographic characteristics of the final sample. METHODS: The 2014 SLCDC-MA is a cross-sectional follow-up survey that includes Canadians from the 10 provinces aged 18 years and older with mood and/or anxiety disorders diagnosed by a health professional that are expected to last, or have already lasted, six months or more. The survey was developed by the Public Health Agency of Canada (PHAC) through an iterative, consultative process with Statistics Canada and external experts. Statistics Canada performed content testing, designed the sampling frame and strategies and collected and processed the data. PHAC used descriptive analyses to describe the respondents' sociodemographic characteristics, produced nationally representative estimates using survey weights provided by Statistics Canada, and generated variance estimates using bootstrap methodology. RESULTS: The final 2014 SLCDC-MA sample consists of a total of 3361 respondents (68.9% response rate). Among Canadian adults with mood and/or anxiety disorders, close to twothirds (64%) were female, over half (56%) were married/in a common-law relationship and 60% obtained a post-secondary education. Most were young or middle-aged (85%), Canadian born (88%), of non-Aboriginal status (95%), and resided in an urban setting (82%). Household income was fairly evenly distributed between the adequacy quintiles; however, individuals were more likely to report a household income adequacy within the lowest (23%) versus highest (17%) quintile. Forty-five percent reported having a mood disorder only, 24% an anxiety disorder only and 31% both kinds of disorder. CONCLUSION: The 2014 SLCDC-MA is the only national household survey to collect information on the experiences of Canadians living with a professionally diagnosed mood and/or anxiety disorder. The information collected offers insights into areas where additional support or interventions may be needed and provides baseline information for future public health research in the area of mental illness.

INTRODUCTION: Il existe peu de données à propos des répercussions des troubles de l'humeur et d'anxiété sur les Canadiens et sur la gestion de ces troubles. L'Enquête sur les personnes ayant une maladie chronique au Canada ­ Composante des troubles de l'humeur et d'anxiété (EPMCC-THA) de 2014 a été élaborée pour combler les lacunes à ce chapitre. Le but du présent article est de décrire la méthodologie de l'EPMCC-THA de 2014 et de présenter les caractéristiques sociodémographiques de l'échantillon final. MÉTHODOLOGIE: L'EPMCC-THA de 2014 est une enquête transversale de suivi menée auprès de Canadiens des 10 provinces âgés de 18 ans et plus qui souffrent d'un trouble de l'humeur ou d'anxiété diagnostiqué par un professionnel de la santé et dont on s'attend à ce qu'il dure (ou durant depuis déjà) six mois ou plus. L'enquête a été élaborée par l'Agence de la santé publique du Canada (ASPC) au moyen d'un processus itératif et consultatif avec Statistique Canada et des experts externes. Statistique Canada a mis à l'essai le contenu, a conçu la base et les stratégies d'échantillonnage et a recueilli et traité les données. L'ASPC a procédé à des analyses descriptives pour déterminer les caractéristiques sociodémographiques des répondants, a produit des estimations représentatives à l'échelle nationale à l'aide des coefficients de pondération fournis par Statistique Canada et a produit des estimations de la variance à l'aide de la méthode bootstrap. RÉSULTATS: L'échantillon final de l'EPMCC-THA de 2014 était constitué de 3 361 répondants (taux de réponse de 68,9 %). Parmi ceux qui vivaient avec un trouble de l'humeur ou d'anxiété, près des deux tiers (64 %) étaient des femmes, près de la moitié (56 %) étaient mariés ou vivaient en union libre et 60 % avaient obtenu un diplôme d'études postsecondaires. La plupart étaient jeunes ou d'âge moyen (85 %), étaient nés au Canada (88 %), étaient non Autochtones (95 %) et vivaient en milieu urbain (82 %). Le revenu du ménage était distribué assez également entre les quintiles de suffisance du revenu avec cependant un revenu déclaré plus souvent dans le quintile le plus bas (23 %) que dans le plus haut (17 %). Quarante-cinq pour cent ont déclaré avoir un trouble de l'humeur seulement, 24 %, un trouble d'anxiété seulement et 31 %, les deux types de trouble. CONCLUSION: L'EPMCC-THA de 2014 est la seule enquête nationale auprès des ménages ayant recueilli de l'information sur les expériences des Canadiens avec un trouble de l'humeur ou d'anxiété diagnostiqué par un professionnel de la santé. Cette information permet de déterminer les secteurs où un soutien ou des interventions supplémentaires pourraient être requis et fournit un support aux futurs travaux de recherche en santé publique dans le domaine des maladies mentales.

Health status, activity limitations, work-related restrictions and level of disability among Canadians with mood and/or anxiety disorders. / État de santé, limitations d'activité, restrictions professionnelles et degré d'invalidité chez les Canadiens atteints d'un trouble de l'humeur ou d'anxiété.

INTRODUCTION: This study provides the first overview of the perceived general and mental health, activity limitations, work-related restrictions and level of disability, as well as factors associated with disability severity, among Canadian adults with mood and/or anxiety disorders, using a population-based household sample. METHODS: We used data from the 2014 Survey on Living with Chronic Diseases in Canada- Mood and Anxiety Disorders Component. The sample consists of Canadians aged 18 years and older with self-reported mood and/or anxiety disorders from the 10 provinces (n = 3361; response rate 68.9%). We conducted descriptive and multinomial multivariate logistic regression analyses. RESULTS: Among Canadian adults with mood and/or anxiety disorders, over one-quarter reported "fair/poor" general (25.3%) and mental (26.1%) health; more than one-third (36.4%) reported one or more activity limitations; half (50.3%) stated a job modification was required to continue working; and more than one-third (36.5%) had severe disability. Those with concurrent mood and anxiety disorders reported poorer outcomes: 56.4% had one or more activity limitations; 65.8% required a job modification and 49.6% were severely disabled. Upon adjusting for individual characteristics, those with mood and/or anxiety disorders who were older, who had a household income in the lowest or lower-middle adequacy quintile or who had concurrent disorders were more likely to have severe disability. CONCLUSION: Findings from this study affirm that mood and/or anxiety disorders, especially concurrent disorders, are associated with negative physical and mental health outcomes. Results support the role of public health policy and programs aimed at improving the lives of people living with these disorders, in particular those with concurrent disorders.

INTRODUCTION: Cette étude fournit, au moyen d'un échantillon de ménages fondé sur la population, le premier aperçu, chez des Canadiens adultes atteints de troubles de l'humeur ou d'anxiété, de leur état de santé globale et de santé mentale perçu, de leurs limitations fonctionnelles, de leurs restrictions professionnelles et de leur degré d'invalidité, ainsi que des facteurs associés à une invalidité grave. MÉTHODOLOGIE: Nous avons obtenu les données de l'Enquête sur les personnes ayant une maladie chronique au Canada ­ Composante des troubles de l'humeur et d'anxiété. L'échantillon est composé de Canadiens âgés de 18 ans et plus, atteints d'un trouble de l'humeur ou d'anxiété autodéclaré et habitant l'une des 10 provinces (n = 3 361; taux de réponse 68,9 %). Nous avons mené des analyses de régression logistiques multidimensionnelles multinomiales et descriptives. RÉSULTATS: Parmi les Canadiens adultes atteints d'un trouble de l'humeur ou d'anxiété, plus d'un quart ont rapporté un état de santé globale (25,3 %) et de santé mentale (26,1 %) « passable ou médiocre ¼, plus du tiers (36,4 %) ont mentionné avoir une ou plusieurs limitations fonctionnelles, la moitié (50,3 %) ont déclaré qu'une modification de leur emploi a été nécessaire pour continuer à travailler et plus du tiers (36,5 %) souffrait d'une invalidité grave. Les personnes avec troubles de l'humeur et d'anxiété concomitants ont mentionné de moins bons résultats : 56,4 % avaient une ou plusieurs limitations fonctionnelles, 65,8 % ont mentionné qu'une modification de leur emploi a été nécessaire et 49,6 % souffraient d'une invalidité grave. Après ajustement pour les caractéristiques individuelles, les personnes atteintes d'un trouble de l'humeur ou d'anxiété qui étaient plus âgées, dont le revenu familial était situé dans le quintile du plus faible revenu ou du revenu faible à moyen ou qui avaient des troubles concomitants étaient plus susceptibles d'avoir une invalidité grave. CONCLUSION: Les résultats de cette étude confirment que les troubles de l'humeur ou d'anxiété, surtout dans le cas de troubles concomitants, sont associés à des résultats en santé physique et mentale négatifs. Ces constats soutiennent les actions en politique et programmes de santé publique qui visent à améliorer la vie des personnes atteintes de ces troubles, surtout celles qui sont atteintes de troubles concomitants.

Report summary - Mood and Anxiety Disorders in Canada, 2016. / Note de synthèse - Les troubles anxieux et de l'humeur au Canada, 2016.

Mood and Anxiety Disorders in Canada, 2016 is the first publication to include administrative health data from the Canadian Chronic Disease Surveillance System (CCDSS) for the national surveillance of mood and anxiety disorders among Canadians aged one year and older. It features nationally complete CCDSS data up to fiscal year 2009/10, as well as trend data spanning over a decade (1996/97 to 2009/10). The data presented in this report, and subsequent updates, can be accessed via the Public Health Agency of Canada's Chronic Disease Infobase Data Cubes at www.infobase.phac-aspc.gc.ca. Data Cubes are interactive databases that allow users to quickly create tables and graphs using their Web browser. The report demonstrates the Public Health Agency of Canada's commitment to improving data collection and reporting about mental illness, as recommended within Changing Directions, Changing Lives - The Mental Health Strategy for Canada.

RÉSUMÉ: Le rapport Les troubles anxieux et de l'humeur au Canada, 2016 est la première publication à présenter des données administratives sur la santé tirées du Système canadien de surveillance des maladies chroniques (SCSMC) pour la surveillance nationale des troubles de l'humeur et d'anxiété chez les Canadiens d'un an ou plus. Il présente les données nationales complètes les plus récentes du SCSMC jusqu'à l'exercice 2009-2010 ainsi que des données sur les tendances couvrant plus d'une décennie (de 1996-1997 à 2009-2010). Les données présentées ici et leurs mises à jour subséquentes sont consultable à partir des cubes de données de l'Infobase des maladies chroniques de l'Agence de la santé publique du Canada à www.infobase.phac-aspc.gc.ca. Les cubes de données sont des bases de données interactives qui permettent aux utilisateurs de créer rapidement des tableaux et graphiques à l'aide de leur navigateur Web. Le rapport témoigne de l'engagement de l'Agence de la santé publique du Canada à améliorer la collecte de données et la production de rapports sur les troubles mentaux, conformément aux recommandations de Changer les orientations, changer des vies : Stratégie en matière de santé mentale pour le Canada.

Into the black and back: the ecology of brain investment in Neotropical army ants (Formicidae: Dorylinae).

Shifts to new ecological settings can drive evolutionary changes in animal sensory systems and in the brain structures that process sensory information. We took advantage of the diverse habitat ecology of Neotropical army ants to test whether evolutionary transitions from below- to above-ground activity were associated with changes in brain structure. Our estimates of genus-typical frequencies of above-ground activity suggested a high degree of evolutionary plasticity in habitat use among Neotropical army ants. Brain structure consistently corresponded to degree of above-ground activity among genera and among species within genera. The most above-ground genera (and species) invested relatively more in visual processing brain tissues; the most subterranean species invested relatively less in central processing higher-brain centers (mushroom body calyces). These patterns suggest a strong role of sensory ecology (e.g., light levels) in selecting for army ant brain investment evolution and further suggest that the subterranean environment poses reduced cognitive challenges to workers. The highly above-ground active genus Eciton was exceptional in having relatively large brains and particularly large and structurally complex optic lobes. These patterns suggest that the transition to above-ground activity from ancestors that were largely subterranean for approximately 60 million years was followed by re-emergence of enhanced visual function in workers.