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1.
Hum Brain Mapp ; 36(9): 3351-72, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26015271

RESUMEN

Creativity, a multifaceted construct, can be studied in various ways, for example, investigating phases of the creative process, quality of the creative product, or the impact of expertise. Previous neuroimaging studies have assessed these individually. Believing that each of these interacting features must be examined simultaneously to develop a comprehensive understanding of creative behavior, we examined poetry composition, assessing process, product, and expertise in a single experiment. Distinct activation patterns were associated with generation and revision, two major phases of the creative process. Medial prefrontal cortex (MPFC) was active during both phases, yet responses in dorsolateral prefrontal and parietal executive systems (DLPFC/IPS) were phase-dependent, indicating that while motivation remains unchanged, cognitive control is attenuated during generation and re-engaged during revision. Experts showed significantly stronger deactivation of DLPFC/IPS during generation, suggesting that they may more effectively suspend cognitive control. Importantly however, similar overall patterns were observed in both groups, indicating the same cognitive resources are available to experts and novices alike. Quality of poetry, assessed by an independent panel, was associated with divergent connectivity patterns in experts and novices, centered upon MPFC (for technical facility) and DLPFC/IPS (for innovation), suggesting a mechanism by which experts produce higher quality poetry. Crucially, each of these three key features can be understood in the context of a single neurocognitive model characterized by dynamic interactions between medial prefrontal areas regulating motivation, dorsolateral prefrontal, and parietal areas regulating cognitive control and the association of these regions with language, sensorimotor, limbic, and subcortical areas distributed throughout the brain.


Asunto(s)
Encéfalo/fisiología , Creatividad , Lenguaje , Pensamiento/fisiología , Adulto , Mapeo Encefálico/métodos , Función Ejecutiva/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Motivación/fisiología , Competencia Profesional
4.
J Clin Psychiatry ; 81(2)2020 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-32237299

RESUMEN

OBJECTIVE: To present a striking case of new-onset psychosis in a middle-aged woman subsequently diagnosed with behavioral variant frontotemporal dementia (bvFTD). To review the data regarding key red-flag features that may suggest a diagnosis of a neurodegenerative process, and specifically bvFTD, rather than a primary psychotic disorder. To examine the role of genetics, especially mutations of the microtubule-associated protein tau (MAPT) gene, in familial cases of frontotemporal dementia (FTD). DATA SOURCES: The pertinent literature was searched online (PubMed, Google Scholar) using the following search terms: frontotemporal dementia (FTD), Pick's disease, behavioral variant FTD (bvFTD), psychosis, delusions, MAPT, and genetics. No date or language limit was applied. STUDY SELECTION: The case report was generated through detailed assessment of clinical notes, imaging studies, and laboratory results. The brain autopsy was carried out and summarized by our neuropathology team. Previously published literature was selected for inclusion in the review section based on relevance to the topic. RESULTS: A neurodegenerative etiology for psychosis (and specifically bvFTD) should be suspected in patients with progressive deficits in executive function, language, or memory. Other key warning features include the presence of a strong family history of a late-life psychotic disorder (or institutional placement or suicide), loss of empathy, impaired recognition of facial expression, or the development of emotional blunting and apathy, abnormal movements, or seizures. CONCLUSIONS: Neurodegenerative disease should be on the differential diagnosis for any patient presenting with new-onset psychosis and behavioral changes in mid to late adulthood. Should red-flag features be present, early referral to a clinic specializing in dementia is recommended for further evaluation. This case highlights that MAPT mutations can be associated with psychosis in FTD and should be considered in the genetic workup. Ongoing research into the cellular and neural circuit mechanisms of psychosis in neurodegenerative disease may shed light on pathologic processes underlying psychosis in primary psychiatric disorders.


Asunto(s)
Deluciones/diagnóstico , Demencia Frontotemporal/diagnóstico , Trastornos Psicóticos/diagnóstico , Deluciones/etiología , Deluciones/genética , Resultado Fatal , Femenino , Demencia Frontotemporal/complicaciones , Demencia Frontotemporal/genética , Humanos , Persona de Mediana Edad , Trastornos Psicóticos/etiología , Trastornos Psicóticos/genética , Proteínas tau/genética
5.
Am J Med ; 132(10): 1142-1147, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31330129

RESUMEN

Encephalopathy refers to dysfunction of the level or contents of consciousness due to brain dysfunction and can result from global brain insults or focal lesions. The underlying causes of encephalopathy include both primary neurologic and systemic conditions. This article discusses the differential diagnosis of encephalopathy, with a focus on primary neurologic causes. A practical schema for organizing the differential diagnosis is to group etiologies by their pace of onset and evolution (eg, sudden, acute, subacute, chronic).


Asunto(s)
Encefalopatías/diagnóstico , Encefalopatías/etiología , Cognición , Estado de Conciencia , Diagnóstico Diferencial , Humanos
6.
Artículo en Inglés | MEDLINE | ID: mdl-28716886

RESUMEN

Neurodegenerative diseases are a common cause of morbidity and cognitive impairment in older adults. Most clinicians who care for the elderly are not trained to diagnose these conditions, perhaps other than typical Alzheimer's disease (AD). Each of these disorders has varied epidemiology, clinical symptomatology, laboratory and neuroimaging features, neuropathology, and management. Thus, it is important that clinicians be able to differentiate and diagnose these conditions accurately. This review summarizes and highlights clinical aspects of several of the most commonly encountered neurodegenerative diseases, including AD, frontotemporal dementia (FTD) and its variants, progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), Parkinson's disease (PD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and Huntington's disease (HD). For each condition, we provide a brief overview of the epidemiology, defining clinical symptoms and diagnostic criteria, relevant imaging and laboratory features, genetics, pathology, treatments, and differential diagnosis.


Asunto(s)
Enfermedades Neurodegenerativas/diagnóstico , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/patología , Encéfalo/patología , Diagnóstico Diferencial , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/epidemiología , Demencia Frontotemporal/patología , Humanos , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología , Neurología , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/epidemiología , Enfermedad de Parkinson/patología
7.
Clin Cancer Res ; 12(15): 4738-46, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16899625

RESUMEN

PURPOSE: In this study, we investigated the mechanisms by which temozolomide enhances radiation response in glioblastoma cells. EXPERIMENTAL DESIGN: Using a panel of four primary human glioblastoma cell lines with heterogeneous O(6)-methylguanine-DNA methyltransferase (MGMT) protein expression, normal human astrocytes, and U87 xenografts, we investigated (a) the relationship of MGMT status with efficacy of temozolomide-based chemoradiation using a panel of in vitro and in vivo assays; (b) underlying mechanisms by which temozolomide enhances radiation effect in glioblastoma cells; and (c) strategies to overcome resistance to radiation + temozolomide. RESULTS: Temozolomide enhances radiation response most effectively in glioblastomas without detectable MGMT expression. On concurrent radiation + temozolomide administration in MGMT-negative glioblastomas, there seems to be decreased double-strand DNA (dsDNA) repair capacity and enhanced dsDNA damage compared either with radiation alone or with sequentially administered temozolomide. Our data suggest that O(6)-benzylguanine can enhance the antitumor effects of concurrent radiation + temozolomide in MGMT-positive cells by enhancing apoptosis and the degree of dsDNA damage. O(6)-Benzylguanine was most effective when administered concurrently with radiation + temozolomide and had less of an effect when administered with temozolomide in the absence of radiation or when administered sequentially with radiation. Our in vivo data using U87 xenografts confirmed our in vitro findings. CONCLUSIONS: The present study shows that temozolomide enhances radiation response most effectively in MGMT-negative glioblastomas by increasing the degree of radiation-induced double-strand DNA damage. In MGMT-positive glioblastomas, depletion of MGMT by the addition of O(6)-benzylguanine significantly enhances the antitumor effect of concurrent radiation + temozolomide. These are among the first data showing mechanisms of synergy between radiation and temozolomide and the effect of MGMT.


Asunto(s)
Dacarbazina/análogos & derivados , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Terapia Combinada , Daño del ADN , Dacarbazina/administración & dosificación , Dacarbazina/farmacología , Modelos Animales de Enfermedad , Guanina/administración & dosificación , Guanina/análogos & derivados , Guanina/farmacología , Humanos , Metilación , Ratones , Ratones Desnudos , O(6)-Metilguanina-ADN Metiltransferasa/efectos de los fármacos , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , O(6)-Metilguanina-ADN Metiltransferasa/efectos de la radiación , Relación Estructura-Actividad , Temozolomida , Trasplante Heterólogo , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Sci Rep ; 2: 834, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23155479

RESUMEN

The neural correlates of creativity are poorly understood. Freestyle rap provides a unique opportunity to study spontaneous lyrical improvisation, a multidimensional form of creativity at the interface of music and language. Here we use functional magnetic resonance imaging to characterize this process. Task contrast analyses indicate that improvised performance is characterized by dissociated activity in medial and dorsolateral prefrontal cortices, providing a context in which stimulus-independent behaviors may unfold in the absence of conscious monitoring and volitional control. Connectivity analyses reveal widespread improvisation-related correlations between medial prefrontal, cingulate motor, perisylvian cortices and amygdala, suggesting the emergence of a network linking motivation, language, affect and movement. Lyrical improvisation appears to be characterized by altered relationships between regions coupling intention and action, in which conventional executive control may be bypassed and motor control directed by cingulate motor mechanisms. These functional reorganizations may facilitate the initial improvisatory phase of creative behavior.


Asunto(s)
Amígdala del Cerebelo/fisiología , Mapeo Encefálico , Creatividad , Giro del Cíngulo/fisiología , Música , Corteza Prefrontal/fisiología , Adulto , Función Ejecutiva , Humanos , Lenguaje , Imagen por Resonancia Magnética/métodos , Masculino
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