92 research outputs found

    Isotocin neuronal phenotypes differ among social systems in cichlid fishes

    Get PDF
    Social living has evolved numerous times across a diverse array of animal taxa. An open question is how the transition to a social lifestyle has shaped, and been shaped by, the underlying neurohormonal machinery of social behaviour. The nonapeptide neurohormones, implicated in the regulation of social behaviours, are prime candidates for the neuroendocrine substrates of social evolution. Here, we examined the brains of eight cichlid fish species with divergent social systems, comparing the number and size of preoptic neurons that express the nonapeptides isotocin and vasotocin. While controlling for the influence of phylogeny and body size, we found that the highly social cooperatively breeding species (n = 4) had fewer parvocellular isotocin neurons than the less social independently breeding species (n = 4), suggesting that the evolutionary transition to group living and cooperative breeding was associated with a reduction in the number of these neurons. In a complementary analysis, we found that the size and number of isotocin neurons significantly differentiated the cooperatively breeding from the independently breeding species. Our results suggest that isotocin is related to sociality in cichlids and may provide a mechanistic substrate for the evolution of sociality

    Increasing Diversion of Methadone in Vancouver, Canada, 2005-2015

    Get PDF
    Background and Aim: Although methadone, an opioid agonist, has been an effective medication used to treat opioid use disorder for over 40 years, recent studies have found that methadone was identified in more than a quarter of prescription opioid-related deaths among people who use illicit drugs in Vancouver, Canada. Thus, we sought to longitudinally examine the availability of diverted methadone among people who inject drugs (PWID). Design and Methods: Data were collected from three prospective cohorts of PWID in Vancouver, Canada between December 2005 and May 2015. Multivariable generalized estimating equation logistic regression was used to identify temporal trends in the immediate availability of diverted methadone (defined as the ability to acquire illicit methadone in <10 minutes). Results: A total of 2092 participants, including 727 (34.8%) women, were included in the present study. In the multivariable analyses after adjusting for a range of potential confounders, later calendar year (adjusted odds ratio [AOR] = 1.21 per year; 95% confidence interval [CI]: 1.19–1.23) was independently and positively associated with reporting immediate availability of diverted methadone. Conclusions: We observed a significant increase in the reported availability of diverted methadone among PWID over a ten-year follow-up period. Further research is needed to identify strategies to limit methadone diversion and assess the impact of alternative medications that are equally effective but safer, such as buprenorphine/naloxone

    Displaced Voices: A Journal of Migration, Archives and Cultural Heritage, Volume 3 Issue 2 (Autumn 2023)

    Get PDF
    Twentieth Century Histories of Civic Society’s Responses to Crises of Displacement: A Special Issue to mark the 70th Anniversary of Refugee Council Displaced Voices is a biannual digital magazine produced twice a year by the Living Refugee Archive team at the University of East London. Displaced Voices aims to provide a digital platform for activists, archivists, researchers, practitioners and academics to contribute to issues pertaining to refugee and migration history; refugee and migrant rights; social justice; cultural heritage and archives. We welcome a range of contributions to the magazine including articles of between 1000-2000 words; reports on fieldwork in archival collections; book recommendations and reviews; and more creative pieces including (but not limited too) cartoons; photography; and poetry. We would also welcome news on activities; publication of reports, projects; letters and news from your own networks. We welcome submissions from all writers whether you are a student, practitioner, activist or established academic. The Displaced Voices online magazine is born out of the collaborative and intersectional work that we have been undertaking through our work with the refugee and migration archives housed at the University of East London. Our work to date has explored the intersections of refugee and migration studies with narrative and life history research linked to oral history methods and archival approaches to the preservation, documentation and accessibility of archival resources recording the refugee experience. This magazine is a collaborative project between the Living Refugee Archive at the University of East London; the Oral History Society Migration Special Interest Group and the International Association for the Study of Forced Migration Working Group on the History of Forced Migration and Refugees. Thematically we are looking to engage with articles that explore the intersection of refugee and forced migration studies; history and cultural heritage studies; narrative research; oral history and archival science

    Assessing Psychological Well-Being in Mothers of Children with Disability: Evaluation of the Parenting Morale Index and Family Impact of Childhood Disability Scale

    Get PDF
    Objective Process model of stress and coping guided psychometric assessment of two brief measures of psychological well-being: Parenting Morale Index (PMI); Family Impact of Childhood Disability (FICD) scale. Methods Canadian mothers (N = 195) of children with disability (CWD) completed PMI, FICD, and validation measures (Brief Family Assessment Measure [FAM], Personal Well-Being Index, Positive and Negative Affect Schedule, General Self-Efficacy Scale, Social Desirability Scale) via computer-assisted telephone interview. Of these, 154 completed additional validation measures (Center for Epidemiological Studies—Depression Scale, Parenting Stress Index, Family Hardiness Index, Brief FAM) 1 year later. Results Factor structures of PMI and FICD were supported; both demonstrated internal consistency, temporal stability, and convergent and discriminant validity. After 1 year, PMI and FICD jointly predicted depressive symptoms, parenting stress, family hardiness, and family adjustment. Conclusion PMI and FICD can identify mothers of CWD at risk for poor psychological well-being to increase the specificity of supports

    Wild and laboratory exposure to cues of predation risk increases relative brain mass in male guppies

    Get PDF
    There is considerable diversity in brain size within and among species, and substantial dispute over the causes, consequences and importance of this variation. Comparative and developmental studies are essential in addressing this controversy. Predation pressure has been proposed as a major force shaping brain, behaviour and life history. The Trinidadian guppy, Poecilia reticulata, shows dramatic variation in predation pressure across populations. We compared the brain mass of guppies from high and low predation populations collected in the wild. Male but not female guppies exposed to high predation possessed heavier brains for their body size compared to fish from low predation populations. The brain is a plastic organ, so it is possible that the population differences we observed were partly due to developmental responses rather than evolved differences. In a follow‐up study, we raised guppies under cues of predation risk or in a control condition. Male guppies exposed to predator cues early in life had heavier brains relative to their body size than control males, while females showed no significant effect of treatment. Collectively our results suggest that male guppies exposed to predation invest more in neural tissue, and that these differences are at least partly driven by plastic responses

    Consistency and flexibility in solving spatial tasks: different horses show different cognitive styles

    Get PDF
    Individual animals vary in their behaviour and reactions to novel situations. These differences may extend to differences in cognition among individuals. We tested twenty-six horses for their ability to detour around symmetric and asymmetric obstacles. All of the animals were able to get around the barrier to reach a food target, but varied in their approach. Some horses moved slowly but were more accurate in choosing the shortest way. Other horses acted quickly, consistently detoured in the same direction, and did not reliably choose the shortest way. The remaining horses shifted from a faster, directionally consistent response with the symmetric barrier, to a slower but more accurate response with the asymmetric barrier. The asymmetric barrier induced a reduction in heart rate variability, suggesting that this is a more demanding task. The different approaches used to solve the asymmetric task may reflect distinct cognitive styles in horses, which vary among individuals, and could be linked to different personality traits. Understanding equine behaviour and cognition can inform horse welfare and management

    Visual Laterality of Calf–Mother Interactions in Wild Whales

    Get PDF
    Behavioral laterality is known for a variety of vertebrate and invertebrate animals. Laterality in social interactions has been described for a wide range of species including humans. Although evidence and theoretical predictions indicate that in social species the degree of population level laterality is greater than in solitary ones, the origin of these unilateral biases is not fully understood. It is especially poorly studied in the wild animals. Little is known about the role, which laterality in social interactions plays in natural populations. A number of brain characteristics make cetaceans most suitable for investigation of lateralization in social contacts.) in the greatest breeding aggregation in the White Sea. Here we show that young calves (in 29 individually identified and in over a hundred of individually not recognized mother-calf pairs) swim and rest significantly longer on a mother's right side. Further observations along with the data from other cetaceans indicate that found laterality is a result of the calves' preference to observe their mothers with the left eye, i.e., to analyze the information on a socially significant object in the right brain hemisphere.Data from our and previous work on cetacean laterality suggest that basic brain lateralizations are expressed in the same way in cetaceans and other vertebrates. While the information on social partners and novel objects is analyzed in the right brain hemisphere, the control of feeding behavior is performed by the left brain hemisphere. Continuous unilateral visual contacts of calves to mothers with the left eye may influence social development of the young by activation of the contralateral (right) brain hemisphere, indicating a possible mechanism on how behavioral lateralization may influence species life and welfare. This hypothesis is supported by evidence from other vertebrates

    No evidence that footedness in pheasants influences cognitive performance in tasks assessing colour discrimination and spatial ability

    Get PDF
    The differential specialization of each side of the brain facilitates the parallel processing of information and has been documented in a wide range of animals. Animals that are more lateralized as indicated by consistent preferential limb use are commonly reported to exhibit superior cognitive ability as well as other behavioural advantages.We assayed the lateralization of 135 young pheasants (Phasianus colchicus), indicated by their footedness in a spontaneous stepping task, and related this measure to individual performance in either 3 assays of visual or spatial learning and memory. We found no evidence that pronounced footedness enhances cognitive ability in any of the tasks. We also found no evidence that an intermediate footedness relates to better cognitive performance. This lack of relationship is surprising because previous work revealed that pheasants have a slight population bias towards right footedness, and when released into the wild, individuals with higher degrees of footedness were more likely to die. One explanation for why extreme lateralization is constrained was that it led to poorer cognitive performance, or that optimal cognitive performance was associated with some intermediate level of lateralization. This stabilizing selection could explain the pattern of moderate lateralization that is seen in most non-human species that have been studied. However, we found no evidence in this study to support this explanation
    corecore