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1.
J Integr Neurosci ; 8(2): 175-202, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19618486

RESUMO

Behavioral and electrophysiological studies of schizophrenia have consistently demonstrated impairments in the integration of visual features into unified perceptual representations. Specific brain regions involved in this dysfunction, however, remain to be clarified. This study used functional Magnetic Resonance Imaging (fMRI) to examine the relative involvement of visual cortex areas (involved in form perception) and parietal and frontal regions (involved in attention), in the visual integration impairment in schizophrenia. Fourteen patients with schizophrenia and 14 healthy controls were compared on behavioral performance and data acquired via fMRI while completing a contour integration task that had previously been used to identify a visual integration deficit in schizophrenia. The schizophrenia patients demonstrated poorer visual integration than controls. Analyses of peak signal change indicated that while the groups were equivalent in area V1, the schizophrenia group demonstrated reduced signal in areas V2-V4, which are the earliest regions sensitive to global configurations of stimuli. Moreover, whereas the control group demonstrated greater recruitment of prefrontal and parietal areas during perception of integrated forms compared to random stimuli, the schizophrenia group demonstrated greater recruitment of frontal regions during perception of random stimuli. The two groups differed on brain regions involved in form perception even when they were matched on accuracy levels. The visual integration disturbance in schizophrenia involves both deficient basic visual processes (beginning as early as occipital region V2), as well as reduced feedback from visual attention regions that normally serves to amplify relevant visual representations relative to irrelevant information.


Assuntos
Transtornos da Percepção/fisiopatologia , Esquizofrenia/fisiopatologia , Córtex Visual/fisiopatologia , Percepção Visual/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Mapeamento Encefálico/métodos , Retroalimentação/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Transtornos da Percepção/etiologia , Estimulação Luminosa , Psicologia do Esquizofrênico , Córtex Visual/anatomia & histologia , Vias Visuais/fisiopatologia , Adulto Jovem
2.
J Forensic Sci ; 64(2): 460-467, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30231300

RESUMO

Few studies have examined life history and cognitive characteristics unique to female homicide offenders. Understanding these characteristics could aid in risk assessment for extreme violence in this group of offenders. The current study utilized t-tests or chi-square tests to compare 27 female and 81 male homicide offenders on psychiatric, neurologic, criminal, and cognitive characteristics. Additionally, we explored the role of abuse history in female offenders through Kruskal-Wallis or Fisher's exact tests. Results indicate that in comparison with male counterparts, females are more likely to have history of mood disorder, borderline personality disorder, and abuse. Cognitively, female homicide offenders exhibit circumscribed cognitive impairment in verbal abilities and perform similarly to male homicide offenders across most cognitive tasks. Within the female offender group, history of sexual abuse is associated with higher rates of impulsive homicide and poorer verbal abilities. These findings provide preliminary evidence for distinct factors associated with homicide in women.


Assuntos
Criminosos/psicologia , Homicídio/psicologia , Adolescente , Adulto , Idoso , Transtorno da Personalidade Borderline/psicologia , Disfunção Cognitiva/epidemiologia , Traumatismos Craniocerebrais/epidemiologia , Vítimas de Crime/estatística & dados numéricos , Feminino , Psicologia Forense , Humanos , Comportamento Impulsivo , Testes de Inteligência , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/psicologia , Testes Neuropsicológicos , Delitos Sexuais/estatística & dados numéricos , Adulto Jovem
3.
Brain ; 130(Pt 10): 2508-19, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17872928

RESUMO

Traumatic brain injury (TBI) is a serious public health problem. Even injuries classified as mild, the most common, can result in persistent neurobehavioural impairment. Diffuse axonal injury is a common finding after TBI, and is presumed to contribute to outcomes, but may not always be apparent using standard neuroimaging. Diffusion tensor imaging (DTI) is a more recent method of assessing axonal integrity in vivo. The primary objective of the current investigation was to characterize white matter integrity utilizing DTI across the spectrum of chronic TBI of all severities. A secondary objective was to examine the relationship between white matter integrity and cognition. Twenty mild, 17 moderate to severe TBI and 18 controls underwent DTI and neuropsychological testing. Fractional anisotropy, axial diffusivity and radial diffusivity were calculated from the DTI data. Fractional anisotropy was the primary measure of white matter integrity. Region of interest analysis included anterior and posterior corona radiata, cortico-spinal tracts, cingulum fibre bundles, external capsule, forceps minor and major, genu, body and splenium of the corpus callosum, inferior fronto-occipital fasciculus, superior longitudinal fasciculus and sagittal stratum. Cognitive domain scores were calculated from executive, attention and memory testing. Decreased fractional anisotropy was found in all 13 regions of interest for the moderate to severe TBI group, but only in the cortico-spinal tract, sagittal stratum and superior longitudinal fasciculus for the mild TBI group. White Matter Load (a measure of the total number of regions with reduced FA) was negatively correlated with all cognitive domains. Analysis of radial and axial diffusivity values suggested that all severities of TBI can result in a degree of axonal damage, while irreversible myelin damage was only apparent for moderate to severe TBI. The present data emphasize that white matter changes exist on a spectrum, including mild TBI. An index of global white matter neuropathology (White Matter Load) was related to cognitive function, such that greater white matter pathology predicted greater cognitive deficits. Mechanistically, mild TBI white matter changes may be primarily due to axonal damage as opposed to myelin damage. The more severe injuries impact both. DTI provides an objective means for determining the relationship of cognitive deficits to TBI, even in cases where the injury was sustained years prior to the evaluation.


Assuntos
Lesão Encefálica Crônica/patologia , Lesão Encefálica Crônica/psicologia , Encéfalo/patologia , Transtornos Cognitivos/etiologia , Adulto , Anisotropia , Mapeamento Encefálico/métodos , Transtornos Cognitivos/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Testes Neuropsicológicos
4.
Psychiatr Serv ; 63(9): 881-8, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22751905

RESUMO

OBJECTIVE: Dialectical behavior therapy (DBT) is an empirically supported treatment for outpatients with borderline personality disorder. However, the utility of DBT strategies for inpatients with the disorder is unclear. This review summarizes and synthesizes findings from trials of DBT in inpatient settings. METHODS: Multiple research databases were searched for articles published through June 2011 that reported on any implementation of DBT in an inpatient setting to address symptoms related to borderline personality disorder, including suicidal and self-injurious behavior. RESULTS: Eleven studies that reported pre- and posttreatment symptoms related to borderline personality disorder were evaluated. Studies indicated that many variations of standard DBT have been used in inpatient settings, including approaches that do not include phone consultation, that include group therapy only, and that vary in treatment duration (from two weeks to three months). Most studies reported reductions in suicidal ideation, self-injurious behaviors, and symptoms of depression and anxiety, whereas results for reducing anger and violent behaviors were mixed. Follow-up data indicated that symptom reduction was often maintained between one and 21 months posttreatment. On the basis of the evidence, the authors identify essential components of an inpatient DBT package and discuss its potential function as an "intensive orientation" to outpatient DBT services. CONCLUSIONS: There is considerable variation in the configuration and duration of DBT implementation for inpatients with borderline personality disorder. However, findings suggest that DBT may be effective in reducing symptoms related to borderline personality disorder in inpatient settings. Future research should standardize and systematically test inpatient DBT. (Psychiatric Services 63:881-888, 2012; doi: 10.1176/appi.ps.201100311).


Assuntos
Terapia Comportamental/métodos , Transtorno da Personalidade Borderline/terapia , Feminino , Humanos , Masculino
5.
Neuropsychologia ; 49(9): 2527-32, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21600905

RESUMO

BACKGROUND AND OBJECTIVE: The volume of cortical tissue devoted to a function often influences the quality of a person's ability to perform that function. Up to now only white matter correlates of creativity have been reported, and we wanted to learn if the creative visuospatial performance on the figural Torrance Test of Creative Thinking (TTCT) is associated with measurements of cerebral gray matter volume in the regions of the brain that are thought to be important in divergent reasoning and visuospatial processing. METHODS: Eighteen healthy college educated men (mean age=40.78; 15 right-handers) were recruited (via advertisement) as participants. High-resolution MRI scans were acquired on a 1.5T MRI scanner. Voxel-based morphometry regression analyses of TTCT to cortical volume were restrained within the anatomic regions identified. RESULTS: One significant positive focus of association with TTCT emerged within the right parietal lobe gray matter (MNI coordinates: 44, -24, 63; 276 voxels). CONCLUSIONS: Based on theories of parietal lobe function and the requirements of the TTCT, the area observed may be related due to its dominant role in global aspects of attention and visuospatial processing including the capacity for manipulating spatial representations.


Assuntos
Mapeamento Encefálico , Criatividade , Lobo Frontal/fisiologia , Lobo Parietal/fisiologia , Resolução de Problemas/fisiologia , Adulto , Lobo Frontal/anatomia & histologia , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Lobo Parietal/anatomia & histologia , Testes Psicológicos , Valores de Referência , Percepção Espacial/fisiologia
6.
J Aging Res ; 2011: 606871, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22175019

RESUMO

Aging studies consistently show a relationship between decreased gray matter volume and decreased performance on working memory tasks. Few aging studies have investigated white matter changes in relation to functional brain changes during working memory tasks. Twenty-five younger and 25 older adults underwent anatomical magnetic resonance imaging (MRI) scans to measure gray matter volume, diffusion tensor imaging (DTI) to measure fractional anisotropy (FA) as a measure of white matter integrity, and functional magnetic resonance imaging (fMRI) while performing a working memory task. Significant increases in activation (fMRI) were seen in the left dorsal and ventral lateral prefrontal cortex with increased working memory load and with increased age (older showing greater bilateral activation). Partial correlational analyses revealed that even after controlling for age, frontal FA correlated significantly with fMRI activation during performance on the working memory task. These findings highlight the importance of white matter integrity in working memory performance associated with normal aging.

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