Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
2.
Behav Res Methods ; 51(4): 1510-1530, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30719687

RESUMEN

An important question that arises from autobiographical memory research is whether the variables that influence memory in the laboratory also drive memory for autobiographical episodes in real life. We explored this question within the context of e-mail communications and investigated the variables that influence recall for personally familiar names and temporal information in e-mails. We designed a Web-based program that analyzed each participant's year-old sent e-mail archive and applied textual analysis algorithms to identify a set of sentences likely to be memorable. These sentences were then used as the stimuli in a cued recall task. Participants saw two sentences from their sent e-mail as a cue and attempted to recall the name of the e-mail recipient. Participants also rated the vividness of recall for the e-mail conversation and estimated the month in which they had written the e-mail. Linear mixed-effect analyses revealed that recipient name recall accuracy decreased with longer retention intervals and increased with greater frequency of contact with the recipient. Also, with longer retention intervals, participants dated e-mails as being more recent than their actual month. This telescoping error was moderately larger for e-mails with greater sentiment. These findings suggest that memory for personally familiar names and temporal information in e-mails closely follows the patterns for autobiographical memory and proper-name recall found in laboratory settings. This study introduces an innovative, Web-based experimental method for studying the cognitive processes related to autobiographical memories using ecologically valid, naturalistic communications.


Asunto(s)
Correo Electrónico , Memoria Episódica , Escritura , Comunicación , Señales (Psicología) , Humanos , Recuerdo Mental
3.
Hum Brain Mapp ; 37(6): 2185-94, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27028955

RESUMEN

While brain connectivity analyses have been demonstrated to identify ill patients for a number of diseases, their ability to predict cognitive impairment after brain injury is not well established. Traditional post brain injury models, such as stroke, are limited for this evaluation because pre-injury brain connectivity patterns are infrequently available. Patients with severe carotid stenosis, in contrast, often undergo non-emergent revascularization surgery, allowing the collection of pre and post-operative imaging, may experience brain insult due to perioperative thrombotic/embolic infarcts or hypoperfusion, and can suffer post-operative cognitive decline. We hypothesized that a distributed function such as memory would be more resilient in patients with brains demonstrating higher degrees of modularity. To test this hypothesis, we analyzed preoperative structural connectivity graphs (using T1 and DWI MRI) for 34 patients that underwent carotid intervention, and evaluated differences in graph metrics using the Brain Connectivity Toolbox. We found that patients with lower binary component number, binary community number and weighted community number prior to surgery were at greater risk for developing cognitive decline. These findings highlight the promise of brain connectivity analyses to predict cognitive decline following brain injury and serve as a clinical decision support tool. Hum Brain Mapp 37:2185-2194, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Encéfalo/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/cirugía , Disfunción Cognitiva/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Anciano , Estudios de Cohortes , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Pruebas de Estado Mental y Demencia , Vías Nerviosas/diagnóstico por imagen , Pruebas Neuropsicológicas , Riesgo
4.
J Alzheimers Dis ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39031372

RESUMEN

Ethics Review began a decade ago with a mission to identify ethical concerns that hold back innovation and to promote solutions that would move the field forward. Over this time, blood biomarkers for brain pathology and medications that treat that pathology promise to transform research and care. A central problem is that the evidence needed to guide test interpretation and practice is accumulating and there are unanswered questions. At the same time, people living with and at risk for dementia want access to their test results and involvement in their care. We promote dialog among diverse people across many institutions through collaboration with the Advisory Group on Risk Evidence Education for Dementia (AGREEDementia.org). Over the years Ethics Review continues to publish these dialogs and solutions to overcome the paralysis of indecision and ethical concerns.

5.
J Alzheimers Dis ; 90(3): 933-944, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36189600

RESUMEN

Advances in biomarkers, genetics, and other data used as dementia risk evidence (DRE) are increasingly informing clinical diagnosis and management. The purpose of this Mini-Forum is to provide a solutions-based discussion of the ethical and legal gaps and practical questions about how to use and communicate these data. Investigators often use DRE in research. When participants ask for their personal results, investigators have concerns. Will data that was intended to study groups be valid for individuals? Will sharing data cause distress? Debates around sharing DRE became heated when blood-based amyloid tests and amyloid reducing drugs appeared poised to enable clinicians easily to identify people with elevated brain amyloid and reduce it with a drug. Such an approach would transform the traditional role of DRE from investigational to foundational; however, then the high costs, uncertain clinical benefits and risks of the therapy led to an urgent need for education to support clinical decision making. Further complicating DRE use are direct to consumer genetic testing and increasingly available biomarker testing. Withholding DRE becomes less feasible and public education around responsible use and understanding become vital. A critical answer to these legal and ethical issues is supporting education that clearly delineates known risks, benefits, and gaps in knowledge, and communication to promote understanding among researchers, clinicians, patients, and all stakeholders. This paper provides an overview and identifies general concepts and resource documents that support more informed discussions for individuals and interdisciplinary groups.


Asunto(s)
Amiloide , Demencia , Humanos , Biomarcadores , Encéfalo , Incertidumbre , Demencia/diagnóstico
6.
J Alzheimers Dis ; 90(4): 1429-1431, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36314212

RESUMEN

O'Caoimh et al. demonstrated that caregivers or family members could administer and score a brief cognitive screening instrument and detect cognitive impairment with comparable accuracy to similar measures administered in-person by trained staff. This novel approach challenges us to consider the boundaries of how caregivers or other family members are used in remote testing. We discuss the potential risks of administration bias, test integrity, and impacts on the patient and caregiver or family member, and we recommend further research before incorporating this practice into routine clinical or research use.


Asunto(s)
Cuidadores , Disfunción Cognitiva , Humanos , Cuidadores/psicología , Disfunción Cognitiva/diagnóstico , Familia , Cognición
7.
J Alzheimers Dis ; 90(3): 945-952, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36278354

RESUMEN

This Study Participant's Bill of Rights is a call to action for researchers in Alzheimer's disease and related dementias (ADRD) to proactively design clinical studies that provide the option for research participants to learn their individual research results if they choose, and in a manner that ensures study integrity. This Bill of Rights was crafted by a committee of study participants, care partners, representatives of dementia advocacy organizations, and other stakeholders in dementia research for the Advisory Group on Risk Education for Dementia (AGREEDementia). The framework developed by the Multi-Regional Clinical Trials (MRCT) Return of Individual Research Results provides a useful context for researchers to plan their studies and disclosure.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Revelación
8.
J Alzheimers Dis ; 85(4): 1593-1600, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34958013

RESUMEN

BACKGROUND: Despite decades of research efforts, current treatments for Alzheimer's disease (AD) are of limited effectiveness and do not halt the progression of the disease and associated cognitive decline. Studies have shown that repetitive transcranial magnetic stimulation (rTMS) may improve cognition. OBJECTIVE: We conducted a pilot study to investigate the effect of rTMS on cognitive function in Veterans with numerous medical comorbidities. METHODS: Participants underwent 20 sessions, over the course of approximately 4 weeks, of 10 Hz rTMS at the left dorsolateral prefrontal cortex with intensity of 120% resting motor threshold. Outcome measures including memory, language, verbal fluency, and executive functions were acquired at baseline, end of treatment, and 4 months after the last rTMS session. Twenty-six Veterans completed the study (13 in the active rTMS group, 13 in the sham rTMS group). RESULTS: The study protocol was well-tolerated. Active, compared to sham, rTMS showed improved auditory-verbal memory at the end of treatment and at 4-month follow-up. However, the active rTMS group demonstrated a trend in decreased semantic verbal fluency at the end of treatment and at 4-month follow up. CONCLUSION: These preliminary results show rTMS is safe in general in this elderly Veteran population with multiple co-morbidities. Patients in the sham group showed an expected, slight decline in the California Verbal Learning Test scores over the course of the study, whereas the active treatment group showed a slight improvement at the 4-month post-treatment follow up. These effects need to be confirmed by studies of larger sample sizes.


Asunto(s)
Disfunción Cognitiva/terapia , Comorbilidad , Estimulación Magnética Transcraneal/instrumentación , Veteranos/estadística & datos numéricos , Anciano , Enfermedad de Alzheimer/psicología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Proyectos Piloto , Resultado del Tratamiento
9.
Brain Imaging Behav ; 16(3): 1186-1195, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34860349

RESUMEN

Patients with depression who ruminate repeatedly focus on depressive thoughts; however, there are two cognitive subtypes of rumination, reflection and brooding, each associated with different prognoses. Reflection involves problem-solving and is associated with positive outcomes, whereas brooding involves passive, negative, comparison with other people and is associated with poor outcomes. Rumination has also been related to atypical functional hyperconnectivity between the default mode network and subgenual prefrontal cortex. Repetitive pulse transcranial magnetic stimulation of the prefrontal cortex has been shown to alter functional connectivity, suggesting that the abnormal connectivity associated with rumination could potentially be altered. This study examined potential repetitive pulse transcranial magnetic stimulation prefrontal cortical targets that could modulate one or both of these rumination subtypes. Forty-three patients who took part in a trial of repetitive pulse transcranial magnetic stimulation completed the Rumination Response Scale questionnaire and resting-state functional magnetic resonance imaging. Seed to voxel functional connectivity analyses identified an anticorrelation between the left lateral orbitofrontal cortex (-44, 26, -8; k = 172) with the default mode network-subgenual region in relation to higher levels of reflection. Parallel analyses were not significant for brooding or the RRS total score. These findings extend previous studies of rumination and identify a potential mechanistic model for symptom-based neuromodulation of rumination.


Asunto(s)
Trastorno Depresivo Mayor , Estimulación Magnética Transcraneal , Red en Modo Predeterminado , Depresión/diagnóstico por imagen , Depresión/terapia , Humanos , Imagen por Resonancia Magnética , Corteza Prefrontal , Estimulación Magnética Transcraneal/métodos
10.
J Alzheimers Dis ; 90(3): 953-962, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35938255

RESUMEN

The brain changes of Alzheimer's disease and other degenerative dementias begin long before cognitive dysfunction develops, and in people with subtle cognitive complaints, clinicians often struggle to predict who will develop dementia. The public increasingly sees benefits to accessing dementia risk evidence (DRE) such as biomarkers, predictive algorithms, and genetic information, particularly as this information moves from research to demonstrated usefulness in guiding diagnosis and clinical management. For example, the knowledge that one has high levels of amyloid in the brain may lead one to seek amyloid reducing medications, plan for disability, or engage in health promoting behaviors to fight cognitive decline. Researchers often hesitate to share DRE data, either because they are insufficiently validated or reliable for use in individuals, or there are concerns about assuring responsible use and ensuring adequate understanding of potential problems when one's biomarker status is known. Concerns include warning people receiving DRE about situations in which they might be compelled to disclose their risk status potentially leading to discrimination or stigma. The Advisory Group on Risk Evidence Education for Dementia (AGREEDementia) welcomes all concerned with how best to share and use DRE. Supporting understanding in clinicians, stakeholders, and people with or at risk for dementia and clearly delineating risks, benefits, and gaps in knowledge is vital. This brief overview describes elements that made this group effective as a model for other health conditions where there is interest in unfettered collaboration to discuss diagnostic uncertainty and the appropriate use and communication of health-related risk information.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Demencia , Humanos , Demencia/diagnóstico , Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/terapia , Amiloide , Biomarcadores
11.
J Psychiatr Res ; 43(5): 497-502, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18947837

RESUMEN

The corticolimbic dysregulation hypothesis of bipolar disorder suggests that depressive symptoms are related to dysregulation of components of an anterior paralimbic network (anterior cingulate, anterior temporal cortex, dorsolateral prefrontal cortex, parahippocampal gyrus, and amygdala) with excessive anterior limbic activity accompanied by diminished prefrontal activity. In younger patients, such abnormalities tend to resolve with remission of depression, but it remains to be established whether the same is true for older patients. This was a cross-sectional, between-subjects design conducted with 16 euthymic, medicated patients with bipolar disorder (10 type I, six type II) and 11 age-matched healthy controls. All participants were over age 50. Our main outcome measures were relative rates of cerebral metabolism derived from a resting (18)flourodeoxyglucose positron emission tomography scan in specified regions of interest in the corticolimbic network. Resting metabolic rates in bipolar patients were significantly greater than in controls in bilateral amygdalae, bilateral parahippocampal gyri, and right anterior temporal cortex (BA 20, 38); they were significantly lower in bipolar patients than in controls in the bilateral dorsolateral prefrontal cortices (BA 9, 10, 46). The evidence of corticolimbic dysregulation observed is consistent with the hypothesis that bipolar disorder entails progressive, pernicious neurobiological disruptions that may eventually persist during euthymia. Persistent corticolimbic dysregulation may be related to residual affective, behavioral, and cognitive symptoms in older patients with bipolar disorder, even when not experiencing syndromal mood disturbance.


Asunto(s)
Trastorno Bipolar/etiología , Trastorno Bipolar/metabolismo , Encefalopatías Metabólicas/complicaciones , Encefalopatías Metabólicas/diagnóstico , Corteza Cerebral/metabolismo , Sistema Límbico/metabolismo , Envejecimiento/psicología , Biomarcadores/metabolismo , Trastorno Bipolar/tratamiento farmacológico , Encefalopatías Metabólicas/metabolismo , Mapeo Encefálico/métodos , Estudios Transversales , Femenino , Fluorodesoxiglucosa F18 , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Descanso
12.
J Psychiatr Res ; 43(3): 181-8, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18582900

RESUMEN

This study explored whether cerebral metabolic changes seen in treatment resistant and rapid cycling bipolar depression inpatients are also found in an outpatient sample not specifically selected for treatment resistance or rapid cycling. We assessed 15 depressed outpatients with bipolar disorder (six type I and nine type II) who were medication-free for at least 2 weeks and were not predominantly rapid cycling. The average 28-item Hamilton Depression Scale (HAM-D) total score was 33.9. The healthy control group comprised 19 age-matched subjects. All participants received a resting quantitative 18F-fluoro-deoxyglucose positron emission tomography scan. Data analyses were performed with Statistical Parametric Mapping (SPM5). Analyses revealed that depressed patients exhibited similar global metabolism, but decreased absolute regional metabolism in the left much more than right dorsolateral prefrontal cortex, bilateral (left greater than right) insula, bilateral subgenual prefrontal cortex, anterior cingulate, medial prefrontal cortex, ventral striatum, and right precuneus. No region exhibited absolute hypermetabolism. Moreover, HAM-D scores inversely correlated with absolute global metabolism and regional metabolism in the bilateral medial prefrontal gyrus, postcentral gyrus, and middle temporal gyrus. Analysis of relative cerebral metabolism yielded a similar, but less robust pattern of findings. Our findings confirm prefrontal and anterior paralimbic metabolic decreases in cerebral metabolism outside of inpatients specifically selected for treatment resistant and rapid cycling bipolar disorder. Prefrontal metabolic rates were inversely related to severity of depression. There was no evidence of regional hypermetabolism, perhaps because this phenomenon is less robust or more variable than prefrontal hypometabolism.


Asunto(s)
Trastorno Bipolar/metabolismo , Encéfalo/metabolismo , Depresión/metabolismo , Pacientes Ambulatorios , Adulto , Anciano , Ganglios Basales/metabolismo , Trastorno Bipolar/complicaciones , Trastorno Bipolar/diagnóstico por imagen , Corteza Cerebral/metabolismo , Depresión/complicaciones , Depresión/diagnóstico por imagen , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Glucosa/metabolismo , Giro del Cíngulo/metabolismo , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Corteza Prefrontal/metabolismo , Escalas de Valoración Psiquiátrica , Radiofármacos/farmacocinética , Adulto Joven
13.
Am J Geriatr Psychiatry ; 17(12): 1022-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20104059

RESUMEN

OBJECTIVES: To evaluate deficits of delayed free recall in euthymic older patients with bipolar disorder and relate deficits to resting cerebral metabolism. DESIGN: Two group, between subjects. SETTING: Outpatient. PARTICIPANTS: Participants included 16 older adult (mean age, 58.7 years; SD = 7.5) euthymic outpatients with bipolar disorder (10 Type I and 6 Type II) and 11 healthy comparison subjects (mean age, 58.3 years; SD = 5.2). MEASUREMENTS: All participants received resting positron emission tomography with (18)flurodeoxyglucose and, within 10 days, delayed free verbal recall testing with the California Verbal Learning Test II. RESULTS: Patients with bipolar disorder, relative to healthy comparison subjects, had significantly poorer delayed free verbal recall. In patients with bipolar disorder, relative to healthy comparison subjects, prefrontal hypometabolism (dorsolateral prefrontal cortex) and paralimbic hypermetabolism (hippocampus, parahippocampal gyrus, and superior temporal gyrus) was associated with recall deficits in patients with bipolar disorder. Prefrontal and limbic metabolism were inversely related. CONCLUSION: Our findings demonstrate an association between prefrontal hypometabolism and paralimbic hypermetabolism and verbal memory deficits in euthymic older patients with bipolar disorder. Verbal memory deficits may be a clinical consequence of corticolimbic dysregulation in bipolar disorder, even during euthymia. This suggests that such dysregulation and related deficits could be bipolar disorder traits.


Asunto(s)
Trastorno Bipolar/metabolismo , Encefalopatías Metabólicas/metabolismo , Sistema Límbico/metabolismo , Recuerdo Mental , Corteza Prefrontal/metabolismo , Descanso , Aprendizaje Verbal , Envejecimiento , Trastorno Bipolar/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Encefalopatías Metabólicas/diagnóstico por imagen , Femenino , Fluorodesoxiglucosa F18 , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Sistema Límbico/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas/estadística & datos numéricos , Tomografía de Emisión de Positrones/métodos , Corteza Prefrontal/diagnóstico por imagen , Radiofármacos
14.
Psychiatry Res ; 172(3): 200-4, 2009 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-19351579

RESUMEN

Mood states are associated with alterations in cerebral blood flow and metabolism, yet changes in cerebral structure are typically viewed in the context of enduring traits, genetic predispositions, or the outcome of chronic psychiatric illness. Magnetic resonance imaging (MRI) scans were obtained from two groups of patients with bipolar disorder. In one group, patients met criteria for a current major depressive episode whereas in the other no patient did. No patient in either group met criteria for a current manic, hypomanic, or mixed episode. Groups were matched with respect to age and illness severity. Analyses of gray matter density were performed with Statistical Parametric Mapping software (SPM5). Compared with non-depressed bipolar subjects, depressed bipolar subjects exhibited lower gray matter density in the right dorsolateral and bilateral dorsomedial prefrontal cortices and portions of the left parietal lobe. In addition, gray matter density was greater in the left temporal lobe and right posterior cingulate cortex/parahippocampal gyrus in depressed than in non-depressed subjects. Our findings highlight the importance of mood state in structural studies of the brain-an issue that has received insufficient attention to date. Moreover, our observed differences in gray matter density overlap metabolic areas of change and thus have implications for the conceptualization and treatment of affective disorders.


Asunto(s)
Trastorno Bipolar/patología , Trastorno Bipolar/psicología , Trastorno Depresivo Mayor/patología , Trastorno Depresivo Mayor/psicología , Imagen por Resonancia Magnética , Corteza Prefrontal/patología , Adulto , Trastorno Bipolar/diagnóstico , Estudios de Casos y Controles , Trastorno Depresivo Mayor/diagnóstico , Femenino , Lateralidad Funcional , Giro del Cíngulo/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Lóbulo Parietal/patología , Escalas de Valoración Psiquiátrica , Adulto Joven
15.
Curr Pain Headache Rep ; 13(1): 12-7, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19126365

RESUMEN

Transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) are two noninvasive brain stimulation techniques that can modulate activity in specific regions of the cortex. At this point, their use in brain stimulation is primarily investigational; however, there is clear evidence that these tools can reduce pain and modify neurophysiologic correlates of the pain experience. TMS has also been used to predict response to surgically implanted stimulation for the treatment of chronic pain. Furthermore, TMS and tDCS can be applied with other techniques, such as event-related potentials and pharmacologic manipulation, to illuminate the underlying physiologic mechanisms of normal and pathological pain. This review presents a description and overview of the uses of two major brain stimulation techniques and a listing of useful references for further study.


Asunto(s)
Encéfalo/fisiología , Manejo del Dolor , Dolor/fisiopatología , Estimulación Magnética Transcraneal/métodos , Animales , Terapia por Estimulación Eléctrica/instrumentación , Terapia por Estimulación Eléctrica/métodos , Humanos , Dimensión del Dolor/instrumentación , Dimensión del Dolor/métodos , Estimulación Magnética Transcraneal/instrumentación
16.
J Alzheimers Dis ; 68(4): 1317-1319, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30883360

RESUMEN

The potential for successful disease modifying treatments for Alzheimer's disease (AD) opens up the possibility that there will be a large cohort of patients living with late-stage dementia and poor quality of life. There must thus be a parallel effort to leverage restorative therapies that improve quality of life in these patients. With the potential for stopping the onset of AD in new patients must come a commitment to those patients living with this chronic disability for many more years than first thought. Legal and ethical implications surrounding who makes decisions and equity in receiving care will become increasingly important if AD is no longer a terminal illness.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Toma de Decisiones , Cuidados Paliativos/ética , Calidad de Vida , Ética Médica , Humanos
17.
Alzheimers Dement (N Y) ; 5: 107-117, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31011621

RESUMEN

White matter hyperintensities (WMHs) are frequently seen on brain magnetic resonance imaging scans of older people. Usually interpreted clinically as a surrogate for cerebral small vessel disease, WMHs are associated with increased likelihood of cognitive impairment and dementia (including Alzheimer's disease [AD]). WMHs are also seen in cognitively healthy people. In this collaboration of academic, clinical, and pharmaceutical industry perspectives, we identify outstanding questions about WMHs and their relation to cognition, dementia, and AD. What molecular and cellular changes underlie WMHs? What are the neuropathological correlates of WMHs? To what extent are demyelination and inflammation present? Is it helpful to subdivide into periventricular and subcortical WMHs? What do WMHs signify in people diagnosed with AD? What are the risk factors for developing WMHs? What preventive and therapeutic strategies target WMHs? Answering these questions will improve prevention and treatment of WMHs and dementia.

18.
Neuroimage Clin ; 18: 553-559, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29868451

RESUMEN

Carotid revascularization (endarterectomy, stenting) prevents stroke; however, procedure-related embolization is common and results in small brain lesions easily identified by diffusion weighted magnetic resonance imaging (DWI). A crucial barrier to understanding the clinical significance of these lesions has been the lack of a statistical approach to identify vulnerable brain areas. The problem is that the lesions are small, numerous, and non-overlapping. Here we address this problem with a new method, the Convergence Analysis of Micro-Lesions (CAML) technique, an extension of the Anatomic Likelihood Analysis (ALE). The method combines manual lesion tracing, constraints based on known lesion patterns, and convergence analysis to represent regions vulnerable to lesions as probabilistic brain atlases. Two studies were conducted over the course of 12 years in an active, vascular surgery clinic. An analysis in an initial group of 126 patients at 1.5 T MRI was cross-validated in a second group of 80 patients at 3T MRI. In CAML, lesions were manually defined and center points identified. Brains were aligned according to side of surgery since this factor powerfully determines lesion distribution. A convergence based analysis, was performed on each of these groups. Results indicated the most consistent region of vulnerability was in motor and premotor cortex regions. Smaller regions common to both groups included the dorsolateral prefrontal cortex and medial parietal regions. Vulnerability of motor cortex is consistent with previous work showing changes in hand dexterity associated with these procedures. The consistency of CAML also demonstrates the feasibility of this new approach to characterize small, diffuse, non-overlapping lesions in patients with multifocal pathologies.


Asunto(s)
Encéfalo/diagnóstico por imagen , Estenosis Carotídea/cirugía , Revascularización Cerebral , Mapeo Encefálico , Estenosis Carotídea/diagnóstico por imagen , Endarterectomía , Humanos , Imagen por Resonancia Magnética , Stents
20.
Gerontologist ; 56(1): 115-25, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26615021

RESUMEN

PURPOSE OF THE STUDY: A comparison of longitudinal global cognitive functioning in women Veteran and non-Veteran participants in the Women's Health Initiative (WHI). DESIGN AND METHODS: We studied 7,330 women aged 65-79 at baseline who participated in the WHI Hormone Therapy Trial and its ancillary Memory Study (WHIMS). Global cognitive functioning (Modified Mini-Mental State Examination [3MSE]) in Veterans (n = 279) and non-Veterans (n = 7,051) was compared at baseline and annually for 8 years using generalized linear modeling methods. RESULTS: Compared with non-Veterans, Veteran women were older, more likely to be Caucasian, unmarried, and had higher rates of educational and occupational attainment. Results of unadjusted baseline analyses suggest 3MSE scores were similar between groups. Longitudinal analyses, adjusted for age, education, ethnicity, and WHI trial assignment revealed differences in the rate of cognitive decline between groups over time, such that scores decreased more in Veterans relative to non-Veterans. This relative difference was more pronounced among Veterans who were older, had higher educational/occupational attainment and greater baseline prevalence of cardiovascular risk factors (e.g., smoking) and cardiovascular disease (e.g., angina, stroke). IMPLICATIONS: Veteran status was associated with higher prevalence of protective factors that may have helped initially preserve cognitive functioning. However, findings ultimately revealed more pronounced cognitive decline among Veteran relative to non-Veteran participants, likely suggesting the presence of risks that may impact neuropathology and the effects of which were initially masked by Veterans' greater cognitive reserve.


Asunto(s)
Envejecimiento/psicología , Trastornos del Conocimiento/psicología , Cognición/fisiología , Memoria/fisiología , Veteranos/psicología , Salud de la Mujer , Anciano , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/fisiopatología , Femenino , Humanos , Pruebas Neuropsicológicas , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA