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Bottisham, United Kingdom

Nishida A.,Tokyo Metropolitan Institute of Medical Science | Nishida A.,University College London | Xu K.M.,University of Cambridge | Croudace T.,University of York | And 4 more authors.
Schizophrenia Bulletin

Background: Associations between self-control in adolescence and adult mental health are unclear in the general population; to our knowledge, no study has investigated self-control in relation to psychotic-like symptoms. Aims: To investigate the relationship between adolescent self-control and the midlife mental health outcomes of anxiety and depression symptoms and psychotic-like experiences (PLEs), controlling for the effect of adolescent conduct and emotional problems and for parental occupational social class and childhood cognition. Methods: A population-based sample, the MRC National Survey of Health and Development (the British 1946 birth cohort) was contacted 23 times between ages 6 weeks and 53 years. Teachers completed rating scales to assess emotional adjustment and behaviors, from which factors measuring self-control, behavioral, and emotional problems were extracted. At age 53 years, PLEs were self-reported by 2918 participants using 4 items from the Psychosis Screening Questionnaire; symptoms of anxiety and depression were assessed using the scaled version of the General Health Questionnaire (GHQ-28). Results: After adjustment for the above covariates, poor adolescent self-control was associated with the presence of PLEs in adulthood, specifically hallucinatory experiences at age 53 years, even after adjustment for GHQ-28 scores. Conclusions: Lower self-control in adolescence is a risk factor for hallucinatory experiences in adulthood. © 2014 © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. Source

Barnett J.H.,University of Cambridge | Barnett J.H.,Cambridge Cognition Ltd | Xu K.,Yale University | Heron J.,University of Bristol | And 3 more authors.
American Journal of Medical Genetics, Part B: Neuropsychiatric Genetics

Individual differences in cognitive function are highly heritable and most likely driven by multiple genes of small effect. Well-characterized common functional polymorphisms in the genes MAOA, COMT, and 5HTTLPR each have predictable effects on the availability of the monoamine neurotransmitters dopamine, noradrenaline, and serotonin. We hypothesized that 5HTTLPR genotype would show little association with prefrontal cognitive performance, but that COMT and MAOA would have interacting effects on cognition through their shared influence on prefrontal catecholamine availability. We assessed the individual and epistatic effects of functional polymorphisms in COMT, MAOA, and 5HTTLPR on children's prefrontal cognitive function in nearly 6,000 children from the population-based Avon Longitudinal Study of Parents and Children (ALSPAC). Neither MAOA nor 5HTTLPR polymorphisms showed significant effects on cognitive function. In boys but not girls, there was a modest but statistically significant interaction between MAOA and COMT genotypes such that increased prefrontal catecholamine availability was associated with better working memory. These results suggest that assessment of multiple genes within functionally related systems may improve our understanding of the genetic basis of cognition. © 2010 Wiley-Liss, Inc. Source

Khandaker G.M.,University of Cambridge | Barnett J.H.,University of Cambridge | Barnett J.H.,Cambridge Cognition Ltd | White I.R.,MRC Biostatistics Unit | Jones P.B.,University of Cambridge
Schizophrenia Research

Objective: A premorbid IQ deficit supports a developmental dimension to schizophrenia and its cognitive aspects that are crucial to functional outcome. Better characterisation of the association between premorbid IQ and the disorder may provide further insight into its origin and etiology. We aimed to quantify premorbid cognitive function in schizophrenia through systematic review and meta-analysis of longitudinal, population-based studies, and to characterize the risk of schizophrenia across the entire range of premorbid IQ. Method: Electronic and manual searches identified general population-based cohort or nested case-control studies that measured intelligence before onset of schizophrenic psychosis using standard psychometric tests, and that defined cases using contemporaneous ICD or DSM. Meta-analyses explored dose-response relationships between premorbid cognitive deficit (using full-scale, verbal and performance IQ) and risk of schizophrenia. Meta-regression analyses explored relationships with age of illness onset, change in premorbid intelligence over time and gender differences. Results: Meta-analysis of 4396 cases and over 745. 000 controls from 12 independent studies confirmed significant decrements in premorbid IQ (effect size -0.43) among future cases. Risk of schizophrenia operated as a consistent dose-response effect, increasing by 3.7% for every point decrease in IQ (p<0.0001). Verbal and nonverbal measures were equally affected. Greater premorbid IQ decrement was associated with earlier illness onset (p < 0.0001). There was no evidence of a progressively increasing deficit during the premorbid period toward illness onset. Conclusions: Strong associations between premorbid IQ and risk for schizophrenia, and age of illness onset argue for a widespread neurodevelopmental contribution to schizophrenia that operates across the entire range of intellectual ability. This also suggests higher IQ may be protective in schizophrenia, perhaps by increasing active cognitive reserve. © 2011 Elsevier B.V. Source

Yurko-Mauro K.,Martek Biosciences Corporation | McCarthy D.,Martek Biosciences Corporation | Rom D.,Prosoft Software Inc. | Nelson E.B.,Martek Biosciences Corporation | And 4 more authors.
Alzheimer's and Dementia

Background: Docosahexaenoic acid (DHA) plays an important role in neural function. Decreases in plasma DHA are associated with cognitive decline in healthy elderly adults and in patients with Alzheimer's disease. Higher DHA intake is inversely correlated with relative risk of Alzheimer's disease. The potential benefits of DHA supplementation in age-related cognitive decline (ARCD) have not been fully examined. Objective: Determine effects of DHA administration on improving cognitive functions in healthy older adults with ARCD. Methods: Randomized, double-blind, placebo-controlled, clinical study was conducted at 19 U.S. clinical sites. A total of 485 healthy subjects, aged ≥55 with Mini-Mental State Examination >26 and a Logical Memory (Wechsler Memory Scale III) baseline score ≥1 standard deviation below younger adults, were randomly assigned to 900 mg/d of DHA orally or matching placebo for 24 weeks. The primary outcome was the CANTAB Paired Associate Learning (PAL), a visuospatial learning and episodic memory test. Results: Intention-to-treat analysis demonstrated significantly fewer PAL six pattern errors with DHA versus placebo at 24 weeks (difference score, -1.63 ± 0.76 [-3.1, -0.14, 95% CI], P = .03). DHA supplementation was also associated with improved immediate and delayed Verbal Recognition Memory scores (P < .02), but not working memory or executive function tests. Plasma DHA levels doubled and correlated with improved PAL scores (P < .02) in the DHA group. DHA was well tolerated with no reported treatment-related serious adverse events. Conclusions: Twenty-four week supplementation with 900 mg/d DHA improved learning and memory function in ARCD and is a beneficial supplement that supports cognitive health with aging. Trial Registration: Clinicaltrials.gov, Identifier: NCT0027813. © 2010 The Alzheimers Association. All rights reserved. Source

Barnett J.H.,Massachusetts General Hospital | Barnett J.H.,University of Cambridge | Barnett J.H.,Cambridge Cognition Ltd | Huang J.,Massachusetts General Hospital | And 9 more authors.
Psychological Medicine

Background Some personality characteristics have previously been associated with an increased risk for psychiatric disorder. Longitudinal studies are required in order to tease apart temporary (state) and enduring (trait) differences in personality among individuals with bipolar disorder (BD). This study aimed to determine whether there is a characteristic personality profile in BD, and whether associations between BD and personality are best explained by state or trait effects.Method A total of 2247 participants in the Systematic Treatment Enhancement Program for Bipolar Disorder study completed the NEO Five-Factor Inventory administered at study entry, and at 1 and 2 years.Results Personality in BD was characterized by high neuroticism (N) and openness (O), and low agreeableness (A), conscientiousness (C) and extraversion (E). This profile was replicated in two independent samples, and openness was found to distinguish BD from major depressive disorder. Latent growth modeling demonstrated that manic symptoms were associated with increased E and decreased A, and depressed symptoms with higher N and lower E, A, C and O. During euthymic phases, high N and low E scores predicted a future depression-prone course.Conclusions While there are clear state effects of mood on self-reported personality, personality variables during euthymia predict future course of illness. Personality disturbances in extraversion, neuroticism and openness may be enduring characteristics of patients with BD. © 2011 Cambridge University Press. Source

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