Jennifer H. Barnett

Learn More
BACKGROUND Cognitive endophenotypes may further our understanding of the genetic basis of psychiatric disorders, and the catechol-O-methyltransferase (COMT) gene is a promising candidate gene for both cognitive function and disorder. We conducted a meta-analysis of reported associations between the COMT Val158/108Met polymorphism and measures of memory and(More)
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(More)
BACKGROUND Demonstrating specific cognitive impairments in psychotic disorders is difficult. However, specific deficits in memory and executive functions have often been claimed. The Cambridge Neuropsychological Test Automated Battery (CANTAB) tasks of IDED attention-shifting (an executive task) and visuospatial paired associates learning (PAL, a memory(More)
Attention-deficit/hyperactivity disorder (ADHD) is a prevalent condition associated with cognitive dysfunction. The Cambridge Neuropsychological Test Automated Battery is a computerized set of tests that has been widely used in ADHD and in translation/back-translation. Following a survey of translational research relevant to ADHD in experimental animals, a(More)
OBJECTIVE The study aimed to determine the cognitive effect of the Val108/158Met polymorphism in the catechol-O-methyltransferase (COMT) gene in children before and during puberty. This polymorphism affects cognitive function in healthy adults and may contribute to risk for schizophrenia. METHOD COMT genotype was determined for 8,707 children from the(More)
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(More)
We examined the effect of the catechol-O-methyltransferase (COMT) Val158Met polymorphism (rs4680), on brain structure in a subset (N = 82) of general population members of the Northern Finland 1966 Birth Cohort, selected through a randomization procedure, aged 33-35. Optimised voxel-based morphometry was used to produce grey matter maps from each subject's(More)
BACKGROUND The idea that superior cognitive function acts as a protective factor against dementia and the consequences of head injury is well established. Here we suggest the hypothesis that cognitive reserve is also important in neuropsychiatric disorders including schizophrenia, bipolar disorder and depression. METHOD We review the history of passive(More)
The catechol-O-methyltransferase (COMT) Val(158)Met polymorphism is hypothesized to affect executive function in patient and control populations. Studies inconsistently report better performance on the Wisconsin Card Sort Test (WCST) in individuals with one or more Met alleles. We conducted a meta-analysis of studies published until August 2006 that(More)
Cognitive dysfunction in schizophrenia is an important target for novel therapies. Effectively measuring the cognitive effects of compounds in clinical trials of schizophrenia could be a major barrier to drug development. The Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) programme produced a consensus cognitive battery(More)