5 research outputs found

    Association between ambulatory 24-hour blood pressure levels and brain volume reduction: a cross-sectional elderly population-based study

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    Previous literature has shown mixed results regarding the association between blood pressure levels and brain volume reduction. The objectives of this study were to determine whether high blood pressure levels were associated with focal brain volume reduction and whether high blood pressure-related focal brain volume reduction was associated with a decline in executive function performance. On the basis of a cross-sectional design, 24-hour ambulatory blood pressure measurements, as well as brain morphology from 3-dimensional magnetic resonance images, were assessed among 183 participants (mean, 65 +/- 0.6 years; 62.4% women). Average levels of systolic and diastolic blood pressures, as well as dip, pulse pressure, and mean arterial blood pressure, were used as outcomes. Cortical gray and white matter volumes were determined by automatic calculation using Statistical Parametric Mapping segmentation. Folstein\u27s Mini-Mental State Examination, digit span, part B of Trail Making, and Stroop tests were used to assess executive function performance. Sex, use of antihypertensive drugs, duration of hypertension, leukoaraiosis, body mass index, education level, and total brain matter volume were used as potential confounders. A significant blood pressure-related decrease in gray matter volume of the left supplementary motor areas (Brodmann area 6) and of the left superior and middle frontal gyrus (Brodmann area 8) was shown. No significant decrease was found with white matter volume. Blood pressure-related decreases in gray matter volume were significantly associated with a decline in executive function performance. The association of high blood pressure with brain volume reduction may in part explain blood pressure-related cognitive decline leading to dementia

    Preserved subliminal processing and impaired conscious access in schizophrenia.

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    BACKGROUND: Studies of visual backward masking have frequently revealed an elevated masking threshold in schizophrenia. This finding has frequently been interpreted as indicating a low-level visual deficit. However, more recent models suggest that masking may also involve late and higher-level integrative processes, while leaving intact early bottom-up visual processing. OBJECTIVE: To test the hypothesis that the backward-masking deficit in schizophrenia corresponds to a deficit in the late stages of conscious perception, whereas the subliminal processing of masked stimuli is fully preserved. DESIGN: Twenty-eight patients with schizophrenia and 28 normal control subjects performed 2 backward-masking experiments. We used Arabic digits as stimuli and varied quasi-continuously the interval with a subsequent mask, thus allowing us to progressively unmask the stimuli. We finely quantified their degree of visibility using objective and subjective measures to evaluate the threshold duration for access to consciousness. We also studied the priming effect caused by the variably masked numbers in a comparison task performed on a subsequently presented and highly visible target number. RESULTS: The threshold delay between the digit and mask necessary for the conscious perception of the masked stimulus was longer in patients compared with controls. This higher consciousness threshold in patients was confirmed by an objective and a subjective measure, and both measures were highly correlated for the patients and controls. However, subliminal priming of masked numbers was effective and identical in patients and controls. CONCLUSIONS: Access to conscious report of masked stimuli is impaired in schizophrenia, whereas fast bottom-up processing of the same stimuli, as assessed by subliminal priming, is preserved. These findings suggest a high-level origin of the masking deficit in schizophrenia, although they leave open for further research its exact relation to previously identified bottom-up visual processing abnormalities

    The stop null mice model for schizophrenia displays [corrected] cognitive and social deficits partly alleviated by neuroleptics.

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    International audienceRecently evidence has accumulated that schizophrenia can arise from primary synaptic defects involving structural proteins particularly, microtubule associated proteins. Previous experiments have demonstrated that a STOP (stable tubule only peptide) gene deletion in mice leads to a phenotype mimicking some aspects of positive symptoms classically observed in schizophrenic patients. In the current study, we determined if STOP null mice demonstrate behavioral abnormalities related to the social and cognitive impairments of schizophrenia. Compared with wild-type mice, STOP null mice exhibited deficits in the non-aggressive component of social recognition, short term working memory and social and spatial learning. As described in humans, learning deficits in STOP null mice were poorly sensitive to long term treatment with typical neuroleptics. Since social and cognitive dysfunction have consistently been considered as central features of schizophrenia, we propose that STOP null mice may provide a useful model to understand the neurobiological correlates of social and cognitive defects in schizophrenia and to develop treatments that better target these symptoms

    Condiciones visuales y auditivas en trabajadores que se desempeñan como conductores para prevenir la accidentalidad vial

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    El presente proyecto es una revisión sistemática de literatura realizada mediante la búsqueda, análisis y selección de artículos científicos observacionales descriptivos y observacionales analíticos (casos-controles o cohortes), relacionados con la prevención de alteraciones visuales y daños auditivos en trabajadores que laboran como conductores. Adicionalmente realiza una búsqueda manual de literatura orientada a reconocer la reglamentación disponible sobre los requisitos visuales y auditivos para adquirir licencia de conducción, e identificar elementos a considerar en el diseño e implementación de un sistema de vigilancia epidemiológica visual y auditivo empresarial. Presenta el análisis de 7 artículos seleccionados de la búsqueda en Pubmed, así como datos de la búsqueda manual, encontrando variabilidad en la información registrada sobre los requisitos mínimos para obtener licencia de conducción y sobre el perfil de los profesionales que realizan las pruebas. Se confirma la importancia de realizar anualmente valoración integral del conductor para garantizar condiciones seguras en su desempeño, pues sus habilidades cognitivas, visuales, auditivas y físicas declinan principalmente por la edad y por estilos de vida como consumo de alcohol, drogas o alimentación desbalanceada, entre otros. Frente a la gestión de riesgo, no se menciona de manera explícita acciones específicas en estos sistemas sensoriales, posiblemente por ser menos sintomáticos.Especialista en Salud OcupacionalEspecializació

    Background Examples of Literature Searches on Topics of Interest

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    A zip file of various literature searches & some resources related to our work related to exposure after the Chernobyl accident and as we began looking at helping in Semey Kazakhstan----a collection of literature reviews on various topics we were interested in... eg. establishing a registry of those exposed for longterm follow-up, what we knew about certain areas like genetics and some resources like A Guide to Environmental Resources on the Internet by Carol Briggs-Erickson and Toni Murphy which could be found on the Internet and was written to be used by researchers, environmentalists, teachers and any person who is interested in knowing and doing something about the health of our planet. See more at https://archives.library.tmc.edu/dm-ms211-012-0060
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