The Experts below are selected from a list of 181179 Experts worldwide ranked by ideXlab platform

Gene E Robinson - One of the best experts on this subject based on the ideXlab platform.

  • a role for octopamine in honey bee division of labor
    Brain Behavior and Evolution, 2002
    Co-Authors: David J. Schulz, Andrew B. Barron, Gene E Robinson
    Abstract:

    Efficient division of labor is one of the main reasons for the success of the social insects. In honey bees the division of labor is principally achieved by workers changing tasks as they age. Typically, young adult bees perform a series of tasks within the colony before ultimately making the transition to foraging outside the hive for resources. This lifelong Behavioral Development is a well-characterized example of naturally occurring Behavioral plasticity, but its neural bases are not well understood. Two techniques were used to assess the role of biogenic amines in the transition from in-hive work to foraging, which is the most dramatic and obvious transition in honey bee Behavioral Development. First, associations between amines and tasks were determined by measuring the levels of amines in dissected regions of individual bee brains using HPLC analysis. Second, colonies were orally treated with biogenic amines and effects on the onset of foraging were observed. Octopamine concentration in the antennal lobes of the bee brain was most reliably associated with task: high in foragers and low in nurses regardless of age. In contrast, octopamine in the mushroom bodies, a neighboring neuropil, was associated with age and not behavior, indicating independent modulation of octopamine in these two brain regions. Treating colonies with octopamine resulted in an earlier onset of foraging in young bees. In addition, octopamine levels were not elevated by non-foraging flight, but were already high on return from the first successful foraging trip and subsequently remained high, showing no further change with foraging experience. This observation suggests that octopamine becomes elevated in the antennal lobes in anticipation of foraging and is involved in the release and maintenance of the foraging state. Foraging itself, however, does not modulate octopamine levels. Behaviorally related changes in octopamine are modulated by juvenile hormone, which has also been implicated in the control of honey bee division of labor. Treatment with the juvenile hormone analog methoprene elevated octopamine and octopamine treatment 'rescued' the delay in Behavioral Development caused by experimentally depleting juvenile hormone in bees. Although the pathways linking juvenile hormone and octopamine are presently unknown, it is clear that octopamine acts 'downstream' of juvenile hormone to influence behavior and that juvenile hormone modulates brain octopamine levels. A working hypothesis is that octopamine acts as an activator of foraging by modulating responsiveness to foraging-related stimuli. This is supported by the finding that octopamine treatment increased the response of bees to brood pheromone, a stimulator of foraging activity. Establishing a role for octopamine in honey bee Behavioral Development is a first step in understanding the neural bases of this example of naturally occurring, socially mediated, Behavioral plasticity. The next level of analysis will be to determine precisely where and how octopamine acts in the nervous system to coordinate this complex social behavior.

  • Juvenile hormone paces Behavioral Development in the adult worker honey bee
    Hormones and Behavior, 2000
    Co-Authors: Joseph P. Sullivan, Susan E. Fahrbach, Omar Jassim, Gene E Robinson
    Abstract:

    Behavioral Development in the adult worker honey bee (Apis mellifera), from performing tasks inside the hive to foraging, is associated with an increase in the blood titer of juvenile hormone III (JH), and hormone treatment results in precocious foraging. To study Behavioral Development in the absence of JH we removed its glandular source, the corpora allata, in 1-day-old adult bees. The age at onset of foraging for allatectomized bees in typical colonies was significantly older compared with that of sham-operated bees in 3 out of 4 colonies; this delay was eliminated by hormone replacement in 3 out of 3 colonies. To determine the effects of corpora allata removal on sensitivity to changes in conditions that influence the rate of Behavioral Development, we used “single-cohort” colonies (composed of only young bees) in which some colony members initiate foraging precociously. The age at onset of foraging for allatectomized bees was significantly older compared with that of sham-operated bees in 2 out of 3 colonies, and this delay was eliminated by hormone replacement. Allatectomized bees initiated foraging at significantly younger ages in single-cohort colonies than in typical colonies. These results demonstrate that JH influences the pace of Behavioral Development in honey bees, but is not essential for either foraging or altering Behavioral Development in response to changes in conditions.

  • effects of social environment and worker mandibular glands on endocrine mediated Behavioral Development in honey bees
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1998
    Co-Authors: Zhi Yong Huang, Erika Plettner, Gene E Robinson
    Abstract:

    Previous studies suggest that older honey bee workers possess an inhibitory signal that regulates Behavioral Development in younger bees. To study how this inhibitor is transmitted, bees were reared for 7 days in double-screen cages, single-screen cages, or unrestricted in a typical colony (control bees). Double-screen cages prevented physical contact with colony members while single-screen cages allowed only antennation and food exchange. Bees reared in double-screen cages showed accelerated endocrine and Behavioral Development; they had significantly higher rates of juvenile hormone biosynthesis and juvenile hormone titers than did control bees and also were more likely to become precocious foragers. Relative to the other two groups, bees reared in single-screen cages showed intermediate juvenile hormone biosynthesis rates and titers, and intermediate rates of Behavioral Development. These results indicate that physical contact is required for total inhibition. We also began to test the hypothesis that worker mandibular glands are the sources of an inhibitory signal. Old bees with mandibular glands removed were significantly less inhibitory towards young bees than were sham-operated and unoperated bees. These results suggest that an inhibitor is produced by the worker mandibular glands.

  • effects of social environment and worker mandibular glands on endocrine mediated Behavioral Development in honey bees a neuroethology sensory neural and Behavioral physiology
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1998
    Co-Authors: Zhi Yong Huang, Erika Plettner, Gene E Robinson
    Abstract:

    Previous studies suggest that older honey bee workers possess an inhibitory signal that regulates Behavioral Development in younger bees. To study how this inhibitor is transmitted, bees were reared for 7 days in double-screen cages, single-screen cages, or unrestricted in a typical colony (control bees). Double-screen cages prevented physical contact with colony members while single-screen cages allowed only antennation and food exchange. Bees reared in double-screen cages showed accelerated endocrine and Behavioral Development; they had significantly higher rates of juvenile hormone biosynthesis and juvenile hormone titers than did control bees and also were more likely to become precocious foragers. Relative to the other two groups, bees reared in single-screen cages showed intermediate juvenile hormone biosynthesis rates and titers, and intermediate rates of Behavioral Development. These results indicate that physical contact is required for total inhibition. We also began to test the hypothesis that worker mandibular glands are the sources of an inhibitory signal. Old bees with mandibular glands removed were significantly less inhibitory towards young bees than were sham-operated and unoperated bees. These results suggest that an inhibitor is produced by the worker mandibular glands.

Charles A Nelson - One of the best experts on this subject based on the ideXlab platform.

  • the effects of early psychosocial deprivation on brain and Behavioral Development findings from the bucharest early intervention project
    Development and Psychopathology, 2016
    Co-Authors: Charles A Nelson, Charles H Zeanah
    Abstract:

    The institutional care of young, parentless children (be they orphaned or abandoned) is a practice that dates back centuries. Despite decades of research that document the hazards of institutional care, many countries throughout the world continue to rear children in institutions; indeed, current estimates place the number of parentless children living in institutions at approximately 8 million. The focus of this chapter is the Bucharest Early Intervention Project, which is a randomized controlled trial of foster care as an intervention for early institutionalization. It seeks to examine the Developmental sequelae of early institutional rearing and whether placement into a family—in our case, high-quality foster care—can ameliorate such sequelae. After discussing the context for launching this project and the history of institutional care in Romania, we describe our foster care intervention. We then turn our attention to describing the project itself and its main findings. We conclude by situating the project into a broader framework of Developmental psychopathology. Keywords: sensitive periods; brain Development; psychopathology; attachment; deprivation; brain functioning

  • designing research to study the effects of institutionalization on brain and Behavioral Development the bucharest early intervention project
    Development and Psychopathology, 2003
    Co-Authors: Charles H Zeanah, Charles A Nelson, Nathan A Fox, Anna T Smyke, Peter J Marshall, Susan W Parker, Sebastian F Koga
    Abstract:

    This paper provides an overview of the largest longitudinal investigation of institutionalized children less than 2 years old ever conducted. The Bucharest Early Intervention Project is an ongoing randomized controlled trial of foster placement as an alternative to institutionalization in abandoned infants and toddlers being conducted in Bucharest, Romania. In addition to describing the contexts in which this study is imbedded, we also provide an overview of the sample, the measures, and the intervention. We hope that the natural experiment of institutionalization will allow us to examine directly the effects of intervention on early deprivation. We hope it will provide answers to many of the critical questions that Developmentalists have asked about the effects of early experience, the timing of deprivation, and the ameliorating effects of early intervention and provide clues to which underlying neurobiological processes are compromised by, and resilient to, dramatic changes in early experience.

Emily Simonoff - One of the best experts on this subject based on the ideXlab platform.

  • Tobacco, alcohol and drug use in eight- to sixteen-year-old twins: the Virginia Twin Study of Adolescent Behavioral Development.
    Journal of studies on alcohol, 1999
    Co-Authors: Hermine H Maes, Joanne M Meyer, Judy L Silberg, John K Hewitt, Michael Rutter, Emily Simonoff, Andrew Pickles, Charlene E. Woodard, Lenn Murrelle, René Carbonneau
    Abstract:

    Objective: This study reports prevalences of lifetime and current alcohol, tobacco and drug use in adolescents; examines associations between substance use and a number of putative risk factors; and estimates the contribution of genetic, shared and unique environmental influences on substance use. Method: Substance use data were collected using the Child and Adolescent Psychiatric Assessment on a population sample of 1,412 male and female monozygotic and dizygotic twin pairs, aged 8 through 16, from the Virginia Twin Study of Adolescent Behavioral Development. Results: Heritabilities were estimated to be 84% and 82% for liability to lifetime and current tobacco use, respectively. For alcohol use the role of genes and environment varied according to the context of reporting. Liability to lifetime alcohol use was estimated to be under environmental control, with 71% of the variation shared by members of a twin pair and 29% unique to individual twins. Lifetime alcohol use without the permission of a parent o...

  • genetics and Developmental psychopathology 2 the main effects of genes and environment on Behavioral problems in the virginia twin study of adolescent Behavioral Development
    Journal of Child Psychology and Psychiatry, 1997
    Co-Authors: Lindon J. Eaves, Joanne M Meyer, Judy L Silberg, Hermine H Maes, Chandra A Reynolds, Michael Rutter, Emily Simonoff, Andrew Pickles, Andrew C. Heath, Kimberly R Truett
    Abstract:

    : Little is known about the contribution of genetic and environmental factors to risk for juvenile psychopathology. The Virginia Twin Study of Adolescent Behavioral Development allows these contributions to be estimated. A population-based, unselected sample of 1412 Caucasian twin pairs aged 8-16 years was ascertained through Virginia schools. Assessment of the children involved semi-structured face-to-face interviews with both twins and both parents using the Child and Adolescent Psychiatric Assessment (CAPA). Self-report questionnaires were also completed by parents, children, and teachers. Measures assessed DSM-III-R symptoms of Attention Deficit Hyperactivity Disorder (ADHD). Conduct Disorder, Oppositional Defiant Disorder, Overanxious Disorder, Separation Anxiety, and Depressive Disorder. Factorially derived questionnaire scales were also extracted. Scores were normalized and standardized by age and sex. Maximum likelihood methods were used to estimate contributions of additive and nonadditive genetic effects, the shared and unique environment, and sibling imitation or contrast effects. Estimates were tested for heterogeneity over sexes. Generally, monozygotic (MZ) twins correlated more highly than dizygotic (DZ) twins, parental ratings more than child ratings, and questionnaire scales more highly than interviews. DZ correlations were very low for measures of ADHD and DZ variances were greater than MZ variances for these variables. Correlations sometimes differed between sexes but those for boy-girl pairs were usually similar to those for like-sex pairs. Most of the measures showed small to moderate additive genetic effects and moderate to large effects of the unique individual environment. Measures of ADHD and related constructs showed marked sibling contrast effects. Some measures of oppositional behavior and conduct disorder showed shared environmental effects. There were marked sex differences in the genetic contribution to separation anxiety, otherwise similar genetic effects appear to be expressed in boys and girls. Effects of rater biases on the genetic analysis are considered. The study supports a widespread influence of genetic factors on risk to adolescent psychopathology and suggests that the contribution of different types of social influence may vary consistently across domains of measurement.

  • the virginia twin study of adolescent Behavioral Development influences of age sex and impairment on rates of disorder
    Archives of General Psychiatry, 1997
    Co-Authors: Emily Simonoff, Joanne M Meyer, Judy L Silberg, Hermine H Maes, Rolf Loeber, John K Hewitt, Michael Rutter, Andrew Pickles, Lindon J. Eaves
    Abstract:

    Background: The Virginia Twin Study of Adolescent Behavioral Development is a cohort-longitudinal epidemiological study that uses the genetic twin design to study the Development and maintenance of child psychiatric disorders. We determined the rates of DSM-III-R disorders, disorders with impairment, and age, sex, and co-morbidity effects. Methods: Families of 2762 white twins aged 8 to 16 years participated. Twins and their parents were asked systematically about risk factors and current psychiatric symptoms by means of investigator-based psychiatric interviews and questionnaires. The DSM-III-R diagnoses were made for major depressive disorder, separation anxiety, overanxious disorder, simple phobia, social phobia, agoraphobia, oppositional defiant disorder, conduct disorder, and attention deficit hyperactivity disorder. Results: The 3-month point prevalence for any DSM-III-R disorders was 413 per 1000, and that for disorders with associated impairment was 142 per 1000. Emotionnal disorders with impairment occurred in 89 per 1000, with girls being more commonly affected; Behavioral disorders had a prevalence of 71 per 1000, with boys being more frequently affected. The proportion with disorder who also had functional impairment varied across disorders; anxiety and phobic disorders were particularly likely not to be accompanied by impairment. Rates of emotional and Behavioral disorders increased over the age range. There was extensive comorbidity among disorders. Conclusions: The prevalence rates and patterns of findings from this study of twins are consistent with those of other epidemiological studies, supporting previous findings of few differences in rates of psychiatric disorder between twins and singletons. The importance of including measures of functional impairment is evident by its effect on rates of disorder and patterns of comorbidity.

  • Genetics and Developmental Psychopathology: 1. Phenotypic Assessment in the Virginia Twin Study of Adolescent Behavioral Development
    Journal of child psychology and psychiatry and allied disciplines, 1997
    Co-Authors: John K Hewitt, Joanne M Meyer, Rolf Loeber, Chandra A Reynolds, Michael Rutter, Emily Simonoff, Andrew Pickles, Andrew C. Heath, Judith L. Silberg, Hermine H Maes
    Abstract:

    We introduce an overlapping cohort sequential longitudinal study of Behavioral Development and psychopathology in a representative sample of 1412 pairs of twins aged 8 through 16 years. Multiple phenotypic assessments involve a full psychiatric interview with each child and each parent, and supplementary parental, teacher, and child interview material and questionnaires. For the first wave of assessments, the numbers of reported DSM-III-R symptoms of Major Depressive Disorder (MDD), Separation Anxiety Disorder (SAD), Overanxious Disorder (OAD), Oppositional Defiant Disorder (ODD), Conduct Disorder (CD), and Attention Deficit Hyperactivity Disorder (ADHD), assessed through interviews, confirm patterns of age and sex trends found in other epidemiological samples, but underscore their dependence on whether the child or the parent is the informant. Correlations across domains for symptoms reported by the same informant are often as large as correlations across informants for the same domain of symptoms. Factor analyses of these symptom counts, taking account of informant view and unreliability of assessment, show the high degree of correlation between SAD and OAD, between MDD and OAD, and between CD and ODD. ADHD symptoms are relatively independent of the other domains, but show moderate correlations with CD, ODD, and MDD. Factorially derived dimensional questionnaire scales, based on child, parental, and teacher reports, show patterns of relationship to symptom counts consistent with both convergent and discriminant validity as indices of liability to clinical symptoms. Across informants, questionnaire scales provide as good a prediction of symptoms as do clinical interviews. Multitrait-multimethod confirmatory factor analysis reveals the patterns of relationship between symptoms of psychiatric disorder in children taking due account of informant and unique sources of variance. Gender differences are consistent within the correlated clusters of ODD/CD and MDD/SAD/OAD, although there are disorder-specific age trends. There are large informant-specific influences on the reporting of symptoms in clinical interviews. Dimensional questionnaire scales provide a useful source of additional information. In subsequent analyses of genetic and environmental etiology of childhood psychopathology we must expect that results may differ by informant and method of assessment. Multivariate and Developmental analyses that explore the sources of these differences will shed new light on the relationship between genetic and environmentally influenced vulnerability and the manifestation of psychopathology in specific circumstances.

  • the virginia twin family study of adolescent Behavioral Development assessing sample biases in demographic correlates of psychopathology
    Psychological Medicine, 1996
    Co-Authors: Joanne M Meyer, Emily Simonoff, J L Silberg, Kenneth S Kendler, John K Hewitt
    Abstract:

    The Virginia Twin-Family Study of Adolescent Behavioral Development (VTSABD) is a current longitudinal study of psychopathology in 1412 pairs of 8-16-year-old Caucasian twins and their parents. The primary aim of the study is to evaluate family-genetic and environmental risk factors for major domains of psychopathology in families representative of the Virginia Caucasian population. In this report, we utilize census-derived indices of neighbourhood income and urban residence to identify departures from population representation arising at the time of family enrollment in the twin registry and family participation in a psychiatric interview. Furthermore, we consider whether demographic sample biases influenced prevalence rates of adult psychopathology (including major depression, generalized anxiety disorder, alcohol dependence, phobias, and panic disorder) in the VTSABD. Results indicated that families that enrolled in the twin registry (83% of those identified by Virginia schools) and that participated in the home interview (75% of those targeted) resided in urban and rural communities with a range of per capita income levels representative of the Virginia population. However, participation biases operated throughout the study and were primarily characterized by losses of families living in low income, urban communities. There was also a smaller number of families living in high income neighbourhoods that did not enroll in the twin registry or that indefinitely postponed the psychiatric interview. These biases had small effects on prevalence rates of adult psychopathology in the VTSABD sample, even though neighbourhood income was significantly related to a subset of adult diagnoses. We emphasize the usefulness of the census methodology in evaluating sample biases in population-based psychiatric genetic studies.

Joanne M Meyer - One of the best experts on this subject based on the ideXlab platform.

  • Tobacco, alcohol and drug use in eight- to sixteen-year-old twins: the Virginia Twin Study of Adolescent Behavioral Development.
    Journal of studies on alcohol, 1999
    Co-Authors: Hermine H Maes, Joanne M Meyer, Judy L Silberg, John K Hewitt, Michael Rutter, Emily Simonoff, Andrew Pickles, Charlene E. Woodard, Lenn Murrelle, René Carbonneau
    Abstract:

    Objective: This study reports prevalences of lifetime and current alcohol, tobacco and drug use in adolescents; examines associations between substance use and a number of putative risk factors; and estimates the contribution of genetic, shared and unique environmental influences on substance use. Method: Substance use data were collected using the Child and Adolescent Psychiatric Assessment on a population sample of 1,412 male and female monozygotic and dizygotic twin pairs, aged 8 through 16, from the Virginia Twin Study of Adolescent Behavioral Development. Results: Heritabilities were estimated to be 84% and 82% for liability to lifetime and current tobacco use, respectively. For alcohol use the role of genes and environment varied according to the context of reporting. Liability to lifetime alcohol use was estimated to be under environmental control, with 71% of the variation shared by members of a twin pair and 29% unique to individual twins. Lifetime alcohol use without the permission of a parent o...

  • genetics and Developmental psychopathology 2 the main effects of genes and environment on Behavioral problems in the virginia twin study of adolescent Behavioral Development
    Journal of Child Psychology and Psychiatry, 1997
    Co-Authors: Lindon J. Eaves, Joanne M Meyer, Judy L Silberg, Hermine H Maes, Chandra A Reynolds, Michael Rutter, Emily Simonoff, Andrew Pickles, Andrew C. Heath, Kimberly R Truett
    Abstract:

    : Little is known about the contribution of genetic and environmental factors to risk for juvenile psychopathology. The Virginia Twin Study of Adolescent Behavioral Development allows these contributions to be estimated. A population-based, unselected sample of 1412 Caucasian twin pairs aged 8-16 years was ascertained through Virginia schools. Assessment of the children involved semi-structured face-to-face interviews with both twins and both parents using the Child and Adolescent Psychiatric Assessment (CAPA). Self-report questionnaires were also completed by parents, children, and teachers. Measures assessed DSM-III-R symptoms of Attention Deficit Hyperactivity Disorder (ADHD). Conduct Disorder, Oppositional Defiant Disorder, Overanxious Disorder, Separation Anxiety, and Depressive Disorder. Factorially derived questionnaire scales were also extracted. Scores were normalized and standardized by age and sex. Maximum likelihood methods were used to estimate contributions of additive and nonadditive genetic effects, the shared and unique environment, and sibling imitation or contrast effects. Estimates were tested for heterogeneity over sexes. Generally, monozygotic (MZ) twins correlated more highly than dizygotic (DZ) twins, parental ratings more than child ratings, and questionnaire scales more highly than interviews. DZ correlations were very low for measures of ADHD and DZ variances were greater than MZ variances for these variables. Correlations sometimes differed between sexes but those for boy-girl pairs were usually similar to those for like-sex pairs. Most of the measures showed small to moderate additive genetic effects and moderate to large effects of the unique individual environment. Measures of ADHD and related constructs showed marked sibling contrast effects. Some measures of oppositional behavior and conduct disorder showed shared environmental effects. There were marked sex differences in the genetic contribution to separation anxiety, otherwise similar genetic effects appear to be expressed in boys and girls. Effects of rater biases on the genetic analysis are considered. The study supports a widespread influence of genetic factors on risk to adolescent psychopathology and suggests that the contribution of different types of social influence may vary consistently across domains of measurement.

  • the virginia twin study of adolescent Behavioral Development influences of age sex and impairment on rates of disorder
    Archives of General Psychiatry, 1997
    Co-Authors: Emily Simonoff, Joanne M Meyer, Judy L Silberg, Hermine H Maes, Rolf Loeber, John K Hewitt, Michael Rutter, Andrew Pickles, Lindon J. Eaves
    Abstract:

    Background: The Virginia Twin Study of Adolescent Behavioral Development is a cohort-longitudinal epidemiological study that uses the genetic twin design to study the Development and maintenance of child psychiatric disorders. We determined the rates of DSM-III-R disorders, disorders with impairment, and age, sex, and co-morbidity effects. Methods: Families of 2762 white twins aged 8 to 16 years participated. Twins and their parents were asked systematically about risk factors and current psychiatric symptoms by means of investigator-based psychiatric interviews and questionnaires. The DSM-III-R diagnoses were made for major depressive disorder, separation anxiety, overanxious disorder, simple phobia, social phobia, agoraphobia, oppositional defiant disorder, conduct disorder, and attention deficit hyperactivity disorder. Results: The 3-month point prevalence for any DSM-III-R disorders was 413 per 1000, and that for disorders with associated impairment was 142 per 1000. Emotionnal disorders with impairment occurred in 89 per 1000, with girls being more commonly affected; Behavioral disorders had a prevalence of 71 per 1000, with boys being more frequently affected. The proportion with disorder who also had functional impairment varied across disorders; anxiety and phobic disorders were particularly likely not to be accompanied by impairment. Rates of emotional and Behavioral disorders increased over the age range. There was extensive comorbidity among disorders. Conclusions: The prevalence rates and patterns of findings from this study of twins are consistent with those of other epidemiological studies, supporting previous findings of few differences in rates of psychiatric disorder between twins and singletons. The importance of including measures of functional impairment is evident by its effect on rates of disorder and patterns of comorbidity.

  • Genetics and Developmental Psychopathology: 1. Phenotypic Assessment in the Virginia Twin Study of Adolescent Behavioral Development
    Journal of child psychology and psychiatry and allied disciplines, 1997
    Co-Authors: John K Hewitt, Joanne M Meyer, Rolf Loeber, Chandra A Reynolds, Michael Rutter, Emily Simonoff, Andrew Pickles, Andrew C. Heath, Judith L. Silberg, Hermine H Maes
    Abstract:

    We introduce an overlapping cohort sequential longitudinal study of Behavioral Development and psychopathology in a representative sample of 1412 pairs of twins aged 8 through 16 years. Multiple phenotypic assessments involve a full psychiatric interview with each child and each parent, and supplementary parental, teacher, and child interview material and questionnaires. For the first wave of assessments, the numbers of reported DSM-III-R symptoms of Major Depressive Disorder (MDD), Separation Anxiety Disorder (SAD), Overanxious Disorder (OAD), Oppositional Defiant Disorder (ODD), Conduct Disorder (CD), and Attention Deficit Hyperactivity Disorder (ADHD), assessed through interviews, confirm patterns of age and sex trends found in other epidemiological samples, but underscore their dependence on whether the child or the parent is the informant. Correlations across domains for symptoms reported by the same informant are often as large as correlations across informants for the same domain of symptoms. Factor analyses of these symptom counts, taking account of informant view and unreliability of assessment, show the high degree of correlation between SAD and OAD, between MDD and OAD, and between CD and ODD. ADHD symptoms are relatively independent of the other domains, but show moderate correlations with CD, ODD, and MDD. Factorially derived dimensional questionnaire scales, based on child, parental, and teacher reports, show patterns of relationship to symptom counts consistent with both convergent and discriminant validity as indices of liability to clinical symptoms. Across informants, questionnaire scales provide as good a prediction of symptoms as do clinical interviews. Multitrait-multimethod confirmatory factor analysis reveals the patterns of relationship between symptoms of psychiatric disorder in children taking due account of informant and unique sources of variance. Gender differences are consistent within the correlated clusters of ODD/CD and MDD/SAD/OAD, although there are disorder-specific age trends. There are large informant-specific influences on the reporting of symptoms in clinical interviews. Dimensional questionnaire scales provide a useful source of additional information. In subsequent analyses of genetic and environmental etiology of childhood psychopathology we must expect that results may differ by informant and method of assessment. Multivariate and Developmental analyses that explore the sources of these differences will shed new light on the relationship between genetic and environmentally influenced vulnerability and the manifestation of psychopathology in specific circumstances.

  • the virginia twin family study of adolescent Behavioral Development assessing sample biases in demographic correlates of psychopathology
    Psychological Medicine, 1996
    Co-Authors: Joanne M Meyer, Emily Simonoff, J L Silberg, Kenneth S Kendler, John K Hewitt
    Abstract:

    The Virginia Twin-Family Study of Adolescent Behavioral Development (VTSABD) is a current longitudinal study of psychopathology in 1412 pairs of 8-16-year-old Caucasian twins and their parents. The primary aim of the study is to evaluate family-genetic and environmental risk factors for major domains of psychopathology in families representative of the Virginia Caucasian population. In this report, we utilize census-derived indices of neighbourhood income and urban residence to identify departures from population representation arising at the time of family enrollment in the twin registry and family participation in a psychiatric interview. Furthermore, we consider whether demographic sample biases influenced prevalence rates of adult psychopathology (including major depression, generalized anxiety disorder, alcohol dependence, phobias, and panic disorder) in the VTSABD. Results indicated that families that enrolled in the twin registry (83% of those identified by Virginia schools) and that participated in the home interview (75% of those targeted) resided in urban and rural communities with a range of per capita income levels representative of the Virginia population. However, participation biases operated throughout the study and were primarily characterized by losses of families living in low income, urban communities. There was also a smaller number of families living in high income neighbourhoods that did not enroll in the twin registry or that indefinitely postponed the psychiatric interview. These biases had small effects on prevalence rates of adult psychopathology in the VTSABD sample, even though neighbourhood income was significantly related to a subset of adult diagnoses. We emphasize the usefulness of the census methodology in evaluating sample biases in population-based psychiatric genetic studies.

Zhi Yong Huang - One of the best experts on this subject based on the ideXlab platform.

  • effects of social environment and worker mandibular glands on endocrine mediated Behavioral Development in honey bees
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1998
    Co-Authors: Zhi Yong Huang, Erika Plettner, Gene E Robinson
    Abstract:

    Previous studies suggest that older honey bee workers possess an inhibitory signal that regulates Behavioral Development in younger bees. To study how this inhibitor is transmitted, bees were reared for 7 days in double-screen cages, single-screen cages, or unrestricted in a typical colony (control bees). Double-screen cages prevented physical contact with colony members while single-screen cages allowed only antennation and food exchange. Bees reared in double-screen cages showed accelerated endocrine and Behavioral Development; they had significantly higher rates of juvenile hormone biosynthesis and juvenile hormone titers than did control bees and also were more likely to become precocious foragers. Relative to the other two groups, bees reared in single-screen cages showed intermediate juvenile hormone biosynthesis rates and titers, and intermediate rates of Behavioral Development. These results indicate that physical contact is required for total inhibition. We also began to test the hypothesis that worker mandibular glands are the sources of an inhibitory signal. Old bees with mandibular glands removed were significantly less inhibitory towards young bees than were sham-operated and unoperated bees. These results suggest that an inhibitor is produced by the worker mandibular glands.

  • effects of social environment and worker mandibular glands on endocrine mediated Behavioral Development in honey bees a neuroethology sensory neural and Behavioral physiology
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1998
    Co-Authors: Zhi Yong Huang, Erika Plettner, Gene E Robinson
    Abstract:

    Previous studies suggest that older honey bee workers possess an inhibitory signal that regulates Behavioral Development in younger bees. To study how this inhibitor is transmitted, bees were reared for 7 days in double-screen cages, single-screen cages, or unrestricted in a typical colony (control bees). Double-screen cages prevented physical contact with colony members while single-screen cages allowed only antennation and food exchange. Bees reared in double-screen cages showed accelerated endocrine and Behavioral Development; they had significantly higher rates of juvenile hormone biosynthesis and juvenile hormone titers than did control bees and also were more likely to become precocious foragers. Relative to the other two groups, bees reared in single-screen cages showed intermediate juvenile hormone biosynthesis rates and titers, and intermediate rates of Behavioral Development. These results indicate that physical contact is required for total inhibition. We also began to test the hypothesis that worker mandibular glands are the sources of an inhibitory signal. Old bees with mandibular glands removed were significantly less inhibitory towards young bees than were sham-operated and unoperated bees. These results suggest that an inhibitor is produced by the worker mandibular glands.