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PubMed2006

Evidence that the outcome of developmental expression of psychosis is worse for adolescents growing up in an urban environment.

BACKGROUND: The urban environment may increase the risk for psychotic disorder in interaction with pre-existing risk for psychosis, but direct confirmation has been lacking. The hypothesis was examined that the outcome of subclinical expression of psychosis during adolescence, as an indicator of psychosis-proneness, would be worse for those growing up in an urban environment, in terms of having a greater probability of psychosis persistence over a 3.5-year period. METHOD: A cohort of 918 adolescents from the Early Developmental Stages of Psychopathology Study (EDSP), aged 14-17 years (mean 15.1 years), growing up in contrasting urban and non-urban environments, completed a self-report measure of psychotic symptoms at baseline (Baseline Psychosis) and at first follow-up around 1 year post-baseline (T1). They were again interviewed by trained psychologists for the presence of psychotic symptoms at the second follow-up on average 3.5 years post-baseline (T2). RESULTS: The rate of T2 psychotic symptoms was 14.2% in those exposed to neither Baseline Psychosis nor Urbanicity, 12.1% in those exposed to Urbanicity alone, 14.9% in those exposed to Baseline Psychosis alone and 29.0% in those exposed to both Baseline Psychosis and Urbanicity. The odds ratio (OR) for the combined exposure was 2.46 [95% confidence interval (CI) 1.46-4.14], significantly greater than that expected if Urbanicity and Baseline Psychosis acted independently. CONCLUSION: These findings support the suggestion that the outcome of the developmental expression of psychosis is worse in urban environments. The environment may impact on risk for psychotic disorder by causing an abnormal persistence of a developmentally common expression of psychotic experiences.

Adolescent↗

PubMed2006

Genetic influences on measures of the environment: a systematic review.

BACKGROUND: Traditional models of psychiatric epidemiology often assume that the relationship between individuals and their environment is unidirectional, from environment to person. Accumulating evidence from developmental and genetic studies has made this perspective increasingly untenable. METHOD: Literature search using Medline, PsycINFO, article references and contact with experts to identify all papers examining the heritability of measures of environments of relevance to psychiatry/psychology. RESULTS: We identified 55 independent studies organized into seven categories: general and specific stressful life events (SLEs), parenting as reported by child, parenting reported by parent, family environment, social support, peer interactions, and marital quality. Thirty-five environmental measures in these categories were examined by at least two studies and produced weighted heritability estimates ranging from 7% to 39%, with most falling between 15% and 35%. The weighted heritability for all environmental measures in all studies was 27%. The weighted heritability for environmental measures by rating method was: self-report 29%, informant report 26%, and direct rater or videotape observation (typically examining 10 min of behavior) 14%. CONCLUSION: Genetic influences on measures of the environment are pervasive in extent and modest to moderate in impact. These findings largely reflect 'actual behavior' rather than 'only perceptions'. Etiologic models for psychiatric illness need to account for the non-trivial influences of genetic factors on environmental experiences.

Child↗

PubMed2004

Effect of enriched environment on Ca2+ uptake via NMDA receptors into barrel cortex slices of spontaneously hypertensive rats.

Exposure to an enriched environment provides animals with informal learning opportunities and is associated with increases in brain size, cortical thickness, neuron size, dendritic branching, spine density, and number of synapses per neuron. The NMDA receptor is involved in synaptic plasticity. This study sought to determine the effect of exposure to an enriched environment on NMDA receptor function in barrel cortex slices of spontaneously hypertensive rats (SHR) and their control Wistar-Kyoto (WKY) rats. An assortment of items such as PVC pipes, metal pipes, metal boxes, metal ladders, and a polystyrene maze, were placed successively in the cages of test animals to create an enriched environment. After 2 weeks, the rats were killed. Their brains were rapidly removed, cooled in continuously oxygenated HEPES buffer (pH 7.4), and sliced in a vibratome to produce 0.35-mm thick slices. The barrel cortex was dissected from slices corresponding to 8.6-4.8 mm anterior to the interaural line and incubated with 45Ca2+ and 100 microM NMDA for 2 min. There was no difference between rats exposed to an enriched environment and rats kept in standard cages. Enrichment of environment did not alter NMDA-stimulated Ca2+ uptake into barrel cortex of SHR and WKY.

Animals↗

PubMed2001

Family environment of children and adolescents with bipolar parents.

OBJECTIVES: The effect of family environment on the development of bipolar disorder (BD) in children is not known. We sought to characterize families with children at high risk for developing BD in order to better understand the contributions of family environment to the development of childhood BD. METHODS: We collected demographic data and parental ratings on the Family Environment Scale (FES) for 56 children (aged 6-18 years) from 36 families with at least one biological parent with BD. The cohort had previously been psychiatrically diagnosed according to semistructured interviews. RESULTS: Statistical comparisons with normative data indicated that parents' ratings were significantly lower on the FES Cohesion and Organization scales and were significantly higher on the FES Conflict scale. Multivariate analyses of variance indicated that families with both parents having a mood disorder had no significantly different FES scores than families with only one parent with a mood disorder (BD). Diagnostic data indicated that while 54% of the children in the sample had an Axis I disorder and 14% had BD, FES scores did not differ significantly for subjects with or without an Axis I disorder, or with or without BD. CONCLUSIONS: Families with a bipolar parent differ from the average family in having less cohesion and organization, and more conflict. Despite this difference, it does not appear that the environment alone of families with a bipolar parent determines the outcome of psychopathology in the children, or that the psychopathology of the children determines the family environment.

Adolescent↗

PubMed2001

Exploring gene-environment interactions: socioregional moderation of alcohol use.

Examples of gene-environment interaction in human behavioral data are relatively rare; those that exist have used simple, dichotomous measures of the environment. The authors describe a model that allows for the specification of more continuous, more realistic variations in environments as moderators of genetic and environmental influences on behavior. Using data from a population-based Finnish twin study, the authors document strong moderating effects of socioregional environments on genetic and environmental influences on adolescent alcohol use, with nearly a five-fold difference in the magnitude of genetic effects between environmental extremes. The incorporation of specific environmental measures into genetically informative designs should prove to be a powerful method for better understanding the nature of gene-environment interaction and its contribution to the etiology of behavioral variation.

Adolescent↗

PubMed2001

Accommodation, occlusion, and disparity matching are used to guide reaching: a comparison of actual versus virtual environments.

The authors used a virtual environment to investigate visual control of reaching and monocular and binocular perception of egocentric distance, size, and shape. With binocular vision, the results suggested use of disparity matching. This was tested and confirmed in the virtual environment by eliminating other information about contact of hand and target. Elimination of occlusion of hand by target destabilized monocular but not binocular performance. Because the virtual environment entails accommodation of an image beyond reach, the authors predicted overestimation of egocentric distances in the virtual relative to actual environment. This was confirmed. The authors used -2 diopter glasses to reduce the focal distance in the virtual environment. Overestimates were reduced by half. The authors conclude that calibration of perception is required for accurate feedforward reaching and that disparity matching is optimal visual information for calibration.

Accommodation, Ocular↗

PubMed2005

Allocentric coding of object-to-object relations in overlearned and novel environments.

R. F. Wang and E. S. Spelke's (2000) finding that disorientation disrupts knowledge is consistent with egocentric but not allocentric coding of object location. The present experiments tested the hypothesis that egocentric coding may dominate early on but that once an allocentric representation is established, then target location is retrieved from it. This hypothesis predicts that disorientation will disrupt configuration knowledge in a novel environment, such as that used by Wang and Spelke, but not in an overlearned environment. Experiments 1 and 2 tested whether disorientation disrupted configuration knowledge of an overlearned environment, and Experiments 3-7 tested whether disorientation disrupted configuration knowledge of a novel, room-sized environment. In none of the experiments did disorientation disrupt configuration knowledge. Hence, in addition to showing allocentric coding of overlearned interlandmark relations, the present findings are consistent with the immediate availability of allocentric location codes in a novel, room-sized environment.

Environment↗

PubMed2001

Influences of self-beliefs, social support, and comfort in the university environment on the academic nonpersistence decisions of American Indian undergraduates.

This study investigated the influence of self-beliefs, social support, and comfort in the university environment on the academic nonpersistence decisions of 83 American Indian undergraduates. The self-belief construct comprised self-esteem and 2 dimensions of college-related self-efficacy. The social support cluster consisted of 3 variables: family support, friend support, and perception of being mentored. The 3rd cluster, comfort in the university environment, was measured by perceptions of university environment, cultural congruity, and college stress. Although each of the 3 constructs significantly accounted for academic nonpersistence decisions, social support was the strongest predictor, followed by comfort in the university environment, and then self-beliefs. Students who perceived being mentored were more likely to report decreased nonpersistence decisions. Similarly, students who had more positive perceptions of the university environment were more likely to make fewer nonpersistence decisions. Finally, higher self-esteem and greater college-related self-efficacy were associated with decreased nonpersistence decisions. Research-informed practice implications for increasing the academic persistence of American Indian students include fostering mentoring relationships and providing interventions to increase social support, self-esteem, and self-efficacy.

Adolescent↗

PubMed1996

The effects of post-weaning environment, biological dam, and nursing dam on feeding neophobia, open field activity, and learning.

Using rats in a cross-fostering design we examined the effects of pre- and post-weaning rearing environments on feeding neophobia, open field activity, runway training, and visual discrimination learning. Fostering had no effect on the offspring behaviors. The animals reared, post-weaning, in an enriched environment consumed more food in a novel situation, were less active in the open field, and learned the first of two discrimination tasks faster than did the animals reared in the standard condition. Inter-correlations among these measures were nonsignificant, suggesting that the effect of environment on learning cannot be reduced to temperamental factors. The deficit in learning resulting from rearing in standard environment does not, however, appear to be irreversible; animals reared in the standard condition reached performance levels on the second discrimination task characteristic of those reared in the enriched environment.

Animals↗

PubMed1980

Behavioral, corticosterone, and prolactin responses to novel environment in rats with fornix transections.

These experiments examined the behavioral, corticosterone, and prolactin responses to a novel environmental in male rats with total fornix transections. During the initial exposure to the novel environment, rats with fornix transections exhibited increased latency to initiate activity and increased activity levels. There were no changes in frequency of rearing, frequency of interactions with objects in the environment, or defecation. Fornix transection was found to have no effect on resting levels of either corticosterone or prolactin but to alter significantly the stress-response profiles of each of these hormones. The corticosterone responses to the novel environment in rats with fornix lesions were of greater magnitude with no change in latency to respond or in recovery of resting levels, whereas the prolactin responses were of shorter latency with no change in magnitude or recovery or resting levels. Habituating to the novel environment by repeated exposure was found to decrease the corticosterone responses of rats with fornix lesions but not the responses of controls. The results are discussed in terms of differences between rats with fornix lesions and control rats in level of arousal and effect of experience in the environment.

Animals↗

PubMed2006

Gene-environment interactions in psychiatry: joining forces with neuroscience.

Gene-environment interaction research in psychiatry is new, and is a natural ally of neuroscience. Mental disorders have known environmental causes, but there is heterogeneity in the response to each causal factor, which gene-environment findings attribute to genetic differences at the DNA sequence level. Such findings come from epidemiology, an ideal branch of science for showing that a gene-environment interactions exist in nature and affect a significant fraction of disease cases. The complementary discipline of epidemiology, experimental neuroscience, fuels gene-environment hypotheses and investigates underlying neural mechanisms. This article discusses opportunities and challenges in the collaboration between psychiatry, epidemiology and neuroscience in studying gene-environment interactions.

Animals↗

PubMed2003

Health correlates of autonomy, control and professional relationships in the nursing work environment.

BACKGROUND: Internationally, nursing is facing a variety of challenges including changes in health systems, an ageing workforce and escalating shortages of Registered Nurses. New Zealand is no exception. Here as elsewhere these challenges are taking their toll on the resources and demands of hospital environments, on the health and well-being of nurses themselves and most certainly on the people for whom they care. In the United States of America (USA), three aspects of the nursing work environment--autonomy, control and nurse-physician relations--have been identified as linked to staff retention, levels of staff burnout and needlestick injury, as well as to a range of patient outcomes. AIM: To examine the New Zealand nursing situation and to see whether aspects of the work environment are associated with health status. METHODS: A total of 225 Registered Nurses in a general hospital completed the Revised Nursing Work Index (NWI-R) and Medical Outcomes Study (MOS) 36-Item Short-Form Health Survey (SF-36). RESULTS: Ratings indicated that the New Zealand hospital environment was characterized by less autonomy and control and better nurse-physician relations than in USA hospitals. Results of correlations demonstrated that more positive ratings of the three workplace attributes were associated with better health status amongst the nurses. The results of regression analyses were indicative either of a confounding relationship or of a mediating relationship such that nurses' relations with physicians, administration and other departments mediate the associations between autonomy, control and health status. CONCLUSIONS: The study offers an insight into a New Zealand hospital environment and suggests the importance of good relationships with physicians and other departments for the health of nurses.

Adult↗

PubMed2001

Enhanced self-determination of adults with intellectual disability as an outcome of moving to community-based work or living environments.

In recent years, the self-determination construct has received increased international visibility and utilization in the field of intellectual disability (ID). This has resulted in efforts to promote skills enhancing self-determination, and in efforts to change how adult services are funded to allocate resources to increase consumer control and direction. An important component to consider in both of these efforts is the role of the environment on self-determination. The present study examined the self-determination, autonomy and life choices of individuals with ID before and after they moved from a more restrictive work or living environment. The self-determination of adults with ID was measured for an average 6-months before and after a move from a more restrictive living or working environment to a community-based setting. Paired-sample t-tests indicated that there were significant changes, in each case in a more adaptive direction, in self-determination, autonomous functioning and life choices following a move to a less restrictive environment. The present findings contribute to emerging evidence that the self-determination of individuals with ID is limited by congregate living or work settings which limit opportunities for choice and decision-making. Alternatively, more normalized, community-based environments support and enhance self-determination. Because self-determination has been linked to positive adult outcomes and enhanced quality of life, it is important to consider ways to enable people with ID to live and work in their communities.

Activities of Daily Living↗

PubMed2002

Family environment and cognitive abilities in girls with fragile-X syndrome.

BACKGROUND: There remains some variance in cognitive ability that is unexplained in children with fragile-X syndrome (FXS). Studies in typically developing children suggest that family environment might be one contributor to this unexplained variance. However, the effect of family environment in relation to cognition in atypical children with FXS has been relatively unexplored to date. METHODS: The present authors examined the putative genetic and environmental factors associated with cognition in a group of age-matched children consisting of 26 females with FXS and 31 typically developing children. All subjects were administered the Wechsler Intelligence Scale for Children-Revised; and the subjects' parents were administered the Wechsler Adult Intelligence Scale-Revised, and completed the Hollingshead Index of Social Status and the Moos & Moos Family Environment Scale. RESULTS: Using a multiple regression analytic strategy, the present authors found that family environment contributed significantly to cognitive abilities in typically developing girls, but did not have a unique contribution to cognitive abilities in girls with FXS. There was a suggestion that, for girls with FXS, socio-economic status, a measure of sociocultural environment, was correlated with IQ. CONCLUSIONS: The present study provides a basis for future research on the environmental contributions to cognitive abilities, particularly work related to verbal cognition.

Cognition↗

PubMed2002

Facilitating infant adaptation: the nursery environment.

The physical and social environment of the nursery is a direct and indirect influence on the development of premature infants. Qualities in the environment affect physiological stability and provide sensory experience that is relevant to brain development. Adaptation of the prematurely born infant to the unexpected surroundings of the neonatal intensive care unit can be facilitated when the infant's developmental needs are understood and characteristics of the environment are adapted accordingly. The need for environmental change is revealed by the infant's behaviour, that is, his interactions with the environment. The environment also affects the behaviour of caregivers, who like the baby need to be able to do their best in this challenging situation.

Adaptation, Physiological↗

PubMed1998

Anna-Monika-Prize paper. Major depression and the environment: a psychiatric genetic perspective.

Genetic factors can interact with environmental factors to influence the vulnerability to major depression (MD) in subtle ways. I explore two such mechanisms: "genetic control of sensitivity to the environment," and "genetic control of exposure to the environment." "Genetic control of sensitivity to the environment" suggests that genes, in part, render individuals relatively vulnerable or relatively invulnerable to the pathogenic effects of environmental stress. In support of this hypothesis, evidence is presented that the depressogenic effect of stressful life events is substantially greater in those at high versus low genetic risk to the MD. "Genetic control of exposure to the environment" suggests that genetic factors influence the probability that individuals will select themselves into high vs. low risk environments. In support of this hypothesis, evidence from a population based twin study suggests that certain classes of stressful life events are modestly heritable. The genetic risk factors for MD in part express themselves by influencing the probability that individuals will experience stressful life events, particularly of an interpersonal nature.

Depressive Disorder↗

PubMed1987

The perception of time in scale model environments.

It has been claimed that when subjects observe differently-scaled model environments their experience of temporal duration is compressed relative to standard clock time in the same proportion as the scale of the model being observed. A series of experiments is reported in which subjects made judgements of duration while observing model environments of different scale. In each experiment, two similar model environments of different scale were presented. Three different kinds of model were used: scale model railways, sitting-room models, and abstract nonrepresentional models. Despite considerable individual variability, significant effects were obtained. Smaller scale was, up to a point, related to a compression of subjective time relative to clock time, although the effect was nowhere near as great as that previously reported. Also, when scale was reduced beyond a certain point the effect on judgements of duration was eliminated, or even reversed. It is suggested that the effect of time compression is related to differences in the density of the information to be processed in environments of different scale, and that there may be an optimum value for information density related both to the scale and to the type of environment.

Adolescent↗

PubMed2006

Genome sequence of Synechococcus CC9311: Insights into adaptation to a coastal environment.

Coastal aquatic environments are typically more highly productive and dynamic than open ocean ones. Despite these differences, cyanobacteria from the genus Synechococcus are important primary producers in both types of ecosystems. We have found that the genome of a coastal cyanobacterium, Synechococcus sp. strain CC9311, has significant differences from an open ocean strain, Synechococcus sp. strain WH8102, and these are consistent with the differences between their respective environments. CC9311 has a greater capacity to sense and respond to changes in its (coastal) environment. It has a much larger capacity to transport, store, use, or export metals, especially iron and copper. In contrast, phosphate acquisition seems less important, consistent with the higher concentration of phosphate in coastal environments. CC9311 is predicted to have differences in its outer membrane lipopolysaccharide, and this may be characteristic of the speciation of some cyanobacterial groups. In addition, the types of potentially horizontally transferred genes are markedly different between the coastal and open ocean genomes and suggest a more prominent role for phages in horizontal gene transfer in oligotrophic environments.

Adaptation, Physiological↗