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1.
Cortex ; 110: 58-68, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29475601

RESUMEN

RATIONALE: Accelerated long-term forgetting (ALF) is a phenomenon found in late onset epilepsy and in transient epileptic amnesia (TEA). Here we evaluated ALF in patients with focal epilepsies and limbic encephalitis (LE) in particular. METHODS: ALF was assessed in 36 patients with focal epilepsy and 154 healthy subjects using an extended version of the Verbal Learning and Memory Test (VLMT), with free recall after 30 min and again after one week. From these patients, 89% had temporal lobe epilepsy; 42% left-lateralized; 39% right; 19% bilateral; 17% were diagnosed with hippocampal sclerosis; 64% displayed features indicating LE; 52% with amygdala pathology, and 61% were antibody positive. ALF was defined as either having unimpaired free recall after 30 min and impaired recall after a week (A) or as a loss in recall exceeding the absolute (B) and percentage loss (C) in the interval of the 30 min and one week recall seen in controls by more than one standard deviation. RESULTS: Repeated measures analysis revealed an association between LE and ALF. Depending on its definition (A, B, or C), ALF was evident in 31%, 42%, or 67% of the patients. Poor verbal memory and ALF (C) were prominent in left-lateralized epilepsies. ALF (A) appeared more frequently in auto-antibody negative patients with LE, ALF (B) less frequently with hippocampal sclerosis. Seizures during the interval did not explain ALF. CONCLUSION: Depending on its definition, ALF is seen in patients with normal or impaired memory at ½ h. ALF seems related to LE but might as well be the first sign of memory impairment in patients with milder epilepsies and not yet definite structural temporal lobe pathology. Longitudinal assessment would be essential for discerning when ALF becomes evident, whether conditions exist in which ALF precedes short-term forgetting, and whether ALF responds to treatment.


Asunto(s)
Encefalitis Límbica/diagnóstico , Trastornos de la Memoria/diagnóstico , Recuerdo Mental/fisiología , Aprendizaje Verbal/fisiología , Adulto , Anciano , Amnesia/diagnóstico , Amnesia/patología , Epilepsia del Lóbulo Temporal/diagnóstico , Epilepsia del Lóbulo Temporal/patología , Femenino , Humanos , Aprendizaje/fisiología , Encefalitis Límbica/patología , Masculino , Memoria/fisiología , Trastornos de la Memoria/patología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Convulsiones/diagnóstico , Lóbulo Temporal/patología
2.
Alzheimers Res Ther ; 9(1): 61, 2017 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-28793933

RESUMEN

BACKGROUND: Neuropsychological testing is considered crucial for differential diagnosis of Alzheimer's disease (AD) and behavioural variant frontotemporal dementia (bvFTD). In-depth neuropsychological assessment revealed specific dysfunctions in the two dementia syndromes. However, a significant overlap of cognitive impairments exists in early disease stages. We questioned whether a standard neuropsychological assessment at initial clinical presentation can delineate patients with AD versus bvFTD. METHODS: In a retrospective approach, we evaluated and compared how cognitive profiles assessed at initial clinical presentation predicted the diagnosis of later verified AD (n = 43) and bvFTD (n = 26). Additionally, the neuropsychological standard domains memory, language, visuospatial skills, executive functions, praxis and social cognition were subjected to stepwise discriminant analysis to compare their differential contribution to diagnosis. RESULTS: Regardless of diagnosis, a percentage of patients presented with major deterioration in a wide range of cognitive domains when compared with age-matched normative data. Only few significant differences were detected on the group level: Patients with AD were relatively more impaired in the verbal recall, verbal recognition, figure copy, and surprisingly in the executive subdomains, set shifting and processing speed whereas bvFTD was characterised by more deficits in imitation of face postures. A combination of tests for verbal recall, imitation of limb and face postures, and figure copy showed the greatest discriminatory power. CONCLUSIONS: Our results imply that the contribution of a standard neuropsychological assessment is limited for differential diagnosis of AD and bvFTD at initial presentation. In contrast to current clinical guidelines, executive functions are neither particularly nor exclusively impaired in patients with bvFTD when assessed within a standard clinical neuropsychological test battery. The significant overlap of bvFTD and AD concerning the profile of cognitive impairments questions current neuropsychological diagnostic criteria and calls for revision, regarding both the degree and the profile of cognitive deficits.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Demencia Frontotemporal/diagnóstico , Pruebas Neuropsicológicas , Anciano , Enfermedad de Alzheimer/psicología , Diagnóstico Diferencial , Escolaridad , Femenino , Demencia Frontotemporal/psicología , Humanos , Masculino , Análisis Multivariante , Estudios Retrospectivos
3.
Front Neurol ; 8: 730, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29387035

RESUMEN

BACKGROUND: Several disease-modifying drugs have shown promising effects on cognitive impairment in multiple sclerosis (MS). Alemtuzumab, a humanized monoclonal antibody, is effective in controlling disease activity, however, has not been evaluated for its effects on cognition in detail so far. OBJECTIVE: To explore the influence of alemtuzumab on cognitive impairment in active relapsing-remitting MS (RRMS) as well as possible clinical and neuroimaging predictors of cognitive changes during the first year of therapy. METHODS: Extensive neuropsychological assessment was administered to 21 patients with active RRMS at baseline and again after the second treatment with alemtuzumab (mean time span: 15.05 months). Clinical and routine structural neuroimaging markers were explored for their capacity to predict individual courses of cognitive change. RESULTS: Overall cognitive functioning remained stable or improved during the observational period of alemtuzumab treatment on average. Scores on two neuropsychological tests of processing speed significantly improved and clinically relevant individual gains of processing speed were seen in the majority of patients. Linear regression models showed that clinical and routine neuroimaging measures of disease activity could not fully account for these cognitive changes. CONCLUSION: Results suggest that alemtuzumab treatment in active RRMS stabilizes overall cognitive functioning and furthermore positively affects cognitive processing speed. Changes in processing speed were independent from clinical and structural neuroimaging parameters of disease activity and may thus represent an underrated and independent outcome measure to evaluate treatment effects.

4.
Neurol Neuroimmunol Neuroinflamm ; 4(1): e307, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27957508

RESUMEN

OBJECTIVE: To report on a novel neuronal target antigen in 3 patients with autoimmune cerebellar degeneration. METHODS: Three patients with subacute to chronic cerebellar ataxia and controls underwent detailed clinical and neuropsychological assessment together with quantitative high-resolution structural MRI. Sera and CSF were subjected to comprehensive autoantibody screening by indirect immunofluorescence assay (IFA) and immunoblot. Immunoprecipitation with lysates of hippocampus and cerebellum combined with mass spectrometric analysis was used to identify the autoantigen, which was verified by recombinant expression in HEK293 cells and use in several immunoassays. Multiparameter flow cytometry was performed on peripheral blood and CSF, and peripheral blood was subjected to T-cell receptor spectratyping. RESULTS: Patients presented with a subacute to chronic cerebellar and brainstem syndrome. MRI was consistent with cortical and cerebellar gray matter atrophy associated with subsequent neuroaxonal degeneration. IFA screening revealed strong immunoglobulin G1 reactivity in sera and CSF with hippocampal and cerebellar molecular and granular layers, but not with a panel of 30 recombinantly expressed established neural autoantigens. Neurochondrin was subsequently identified as the target antigen, verified by IFA and immunoblot with HEK293 cells expressing human neurochondrin as well as the ability of recombinant neurochondrin to neutralize the autoantibodies' tissue reaction. Immune phenotyping revealed intrathecal accumulation and activation of B and T cells during the acute but not chronic phase of the disease. T-cell receptor spectratyping suggested an antigen-specific T-cell response accompanying the formation of antineurochondrin autoantibodies. No such neurochondrin reactivity was found in control cohorts of various neural autoantibody-associated neurologic syndromes, relapsing-remitting multiple sclerosis, cerebellar type of multiple system atrophy, hereditary cerebellar ataxias, other neurologic disorders, or healthy donors. CONCLUSION: Neurochondrin is a neuronal target antigen in autoimmune cerebellar degeneration.

5.
Cortex ; 84: 1-14, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27639684

RESUMEN

Limb apraxia denotes a cognitive impairment of gesture production. Lesion studies in patients with stroke point towards distinct neural processing streams for limb imitation and object-pantomime within left parietal and temporal cortex, respectively. Despite its frequent occurrence as an early symptom in both, Alzheimer's dementia (AD) and behavioural variant frontotemporal dementia (bvFTD), neural correlates of limb apraxia within these patient groups remain unexplored. Using voxel-based morphometry and multiple regression models, associations between limb apraxia and gray matter (GM) volume were investigated in 36 dementia patients (18 AD, 18 bvFTD) in early disease stages. Both dementia subtypes showed a comparable degree of limb apraxia. Although the patient groups showed distinct atrophy patterns with significantly more severe frontal GM loss in bvFTD, we found similar neural correlates of limb apraxia within posterior brain regions for both dementia subtypes: limb-imitation was associated with bilateral atrophy of superior, inferior and medial parietal cortex. Object-pantomime showed associations with GM volume in right middle temporal and angular gyrus. Our results argue for shared neural correlates of limb apraxia in AD and bvFTD and validate the syndrome as an important neuropsychological feature across different etiologies. Moreover, our results are compatible with neural models derived from patients with stroke, suggesting partly distinct neural representations of imitation and pantomime. Compared to patients with stroke however, AD and bvFTD showed more bilateral or even right lateralized neural representations of limb apraxia, proposing a greater influence of visuospatial impairments and spatial body representation deficits on praxis performance.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Ataxia/etiología , Mapeo Encefálico , Demencia Frontotemporal/complicaciones , Adulto , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Atrofia , Conducta , Diagnóstico Precoz , Femenino , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/patología , Demencia Frontotemporal/psicología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Accidente Cerebrovascular/complicaciones
6.
Neurol Neuroimmunol Neuroinflamm ; 3(3): e232, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27213174

RESUMEN

OBJECTIVES: To characterize the cellular autoimmune response in patients with γ-aminobutyric acid (GABA)B receptor antibody-associated limbic encephalitis (GABAB-R LE). METHODS: Patients underwent MRI, extensive neuropsychological assessment, and multiparameter flow cytometry of peripheral blood and CSF. RESULTS: We identified a series of 3 cases of nonparaneoplastic GABAB-R LE and one case of paraneoplastic GABAB-R LE associated with small cell lung cancer. All patients exhibited temporal lobe epilepsy, neuropsychological deficits, and MRI findings typical of LE. Absolute numbers of CD19(+) B cells, CD138(+) CD19(+) plasma cells, CD4(+) T cells, activated HLADR(+) CD4(+) T cells, as well as CD8(+) T cells and HLADR(+) CD8(+) T cells did not differ in peripheral blood but were elevated in CSF of patients with GABAB-R LE compared to controls. Augmented absolute numbers of CD138(+) CD19(+) plasma cells and activated HLADR(+) CD8(+) T cells in CSF corresponded to higher overall neuropsychological and memory deficits in patients with GABAB-R LE. A histologic specimen of one patient following selective amygdalohippocampectomy revealed perivascular infiltrates of CD138(+) plasma cells and CD4(+) T cells, whereas cytotoxic CD8(+) T cells were detected within the brain parenchyma in close contact to neurons. CONCLUSION: Our data suggest a pathogenic role for CD8(+) T cells in addition to the established role of plasma cell-derived autoantibodies in GABAB-R LE.

7.
Neurol Neuroimmunol Neuroinflamm ; 3(2): e207, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26977423

RESUMEN

OBJECTIVE: It was hypothesized that in encephalitides with autoantibodies directed to CNS surface antigens an antibody-removing intervention might speed up recovery. METHODS: The outcome of autoimmune encephalitis in 19 patients with antibodies against surface antigens (leucine-rich, glioma inactivated 1 [LGI1], n = 3; contactin-associated protein-2 [CASPR2], n = 4; NMDA receptor [NMDAR], n = 7) and intracellular antigens (glutamic acid decarboxylase [GAD], n = 5) after immunoadsorption in addition to corticosteroid therapy was evaluated retrospectively. Modified Rankin scale (mRS) scores and data on seizures, memory, and antibody titers directly after immunoadsorption (early follow-up) and after a median of 4 months (late follow-up) were compiled. RESULTS: Immediately after immunoadsorption, 9 of 14 patients with antibodies against LGI1, CASPR2, or NMDAR (64%), but none with GAD antibodies, had improved by at least one mRS point. Five of the 7 patients with LGI1 or CASRP2 antibodies had become seizure-free, and 2 patients with NMDAR antibodies had a memory improvement of more than 1 SD of a normal control population. At late follow-up, 12 of 14 patients with surface antibodies had improved (86%), and none of the patients with GAD antibodies. CONCLUSIONS: It is suggested that addition of immunoadsorption to immunosuppression therapy in patients with surface antibodies may accelerate recovery. This supports the pathogenic role of surface antibodies. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that immunoadsorption combined with immunosuppression therapy is effective in patients with autoimmune encephalitis with surface antibodies.

8.
J Neurol Neurosurg Psychiatry ; 87(12): 1287-1295, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28103199

RESUMEN

BACKGROUND: Susac syndrome is characterised by the triad of encephalopathy with or without focal neurological signs, branch retinal artery occlusions and hearing loss. Establishment of the diagnosis is often delayed because the triad is complete only in a minority of patients at disease onset. This leads to a critical delay in the initiation of appropriate treatment. Our objective was to establish criteria for diagnosis of either definite or probable Susac syndrome. METHOD: The establishment of diagnostic criteria was based on the following three steps: (1) Definition of a reference group of 32 patients with an unambiguous diagnosis of Susac syndrome as assessed by all interdisciplinary experts of the European Susac Consortium (EuSaC) team (EuSaC cohort); (2) selection of diagnostic criteria, based on common clinical and paraclinical findings in the EuSaC cohort and on a review of the literature; and (3) validation of the proposed criteria in the previously published cohort of all Susac cases reported until 2012. RESULTS: Integrating the clinical presentation and paraclinical findings, we propose formal criteria and recommend a diagnostic workup to facilitate the diagnosis of Susac syndrome. More than 90% of the cases in the literature fulfilled the proposed criteria for probable or definite Susac syndrome. We surmise that more patients could have been diagnosed with the recommended diagnostic workup. CONCLUSIONS: We propose diagnostic criteria for Susac syndrome that may help both experts and physicians not familiar with Susac syndrome to make a correct diagnosis and to prevent delayed treatment initiation.


Asunto(s)
Síndrome de Susac/diagnóstico , Adolescente , Adulto , Estudios de Cohortes , Diagnóstico Tardío , Diagnóstico Diferencial , Intervención Médica Temprana , Femenino , Adhesión a Directriz , Humanos , Comunicación Interdisciplinaria , Colaboración Intersectorial , Masculino , Persona de Mediana Edad , Valores de Referencia , Síndrome de Susac/terapia , Adulto Joven
9.
J Alzheimers Dis ; 49(3): 593-605, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26484911

RESUMEN

BACKGROUND: Standardized praxis assessments with modern, empirically validated screening tests have substantially improved clinical evaluation of apraxia in patients with stroke. Although apraxia may contribute to early differential diagnosis of Alzheimer's dementia (AD) and behavioral variant frontotemporal dementia (bvFTD), no comparable test is readily available to clinicians for this purpose to date. OBJECTIVE: To design a clinically useful apraxia test for the differentiation of AD and bvFTD. METHODS: 84 test items pertaining to twelve praxis subdomains were evaluated for their efficacy to discriminate between patients with bvFTD (n = 24), AD (n = 28), and elderly healthy controls (HC; n = 35). Items were then selected based on discriminative value and psychometric properties. RESULTS: Items indicative of mild AD comprised spatially complex imitation of hand and finger postures and to a lesser degree, pantomime of common object-use. Buccofacial apraxia including imitation of face postures, emblematic face postures, and repetition of multisyllabic pseudowords differentiated bvFTD from HC and AD. The final test version consisting of 20 items proved highly efficient for the discrimination of biologically confirmed dementia patients from HC (sensitivity 91% , specificity 71%) but also for differential diagnosis of bvFTD and AD (sensitivity 74% , specificity 93%). CONCLUSIONS: Assessment of praxis profiles effectively contributes to diagnosis and differential diagnosis of AD and bvFTD. The Dementia Apraxia Test (DATE) is a brief and easy to administer cognitive tool for dementia assessment, has a high inter-rater reliability (Cohen's κ= 0.885) and demonstrates content validity.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Apraxias/diagnóstico , Apraxias/etiología , Demencia Frontotemporal/complicaciones , Pruebas Neuropsicológicas , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Psicometría , Valores de Referencia
10.
Front Neurol ; 6: 250, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26648907

RESUMEN

Limbic encephalitis (LE) is an autoimmune-mediated disorder that affects structures of the limbic system, in particular, the amygdala. The amygdala constitutes a brain area substantial for processing of emotional, especially fear-related signals. The amygdala is also involved in neuroendocrine and autonomic functions, including skin conductance responses (SCRs) to emotionally arousing stimuli. This study investigates behavioral and autonomic responses to discrete emotion evoking and neutral film clips in a patient suffering from LE associated with contactin-associated protein-2 (CASPR2) antibodies as compared to a healthy control group. Results show a lack of SCRs in the patient while watching the film clips, with significant differences compared to healthy controls in the case of fear-inducing videos. There was no comparable impairment in behavioral data (emotion report, valence, and arousal ratings). The results point to a defective modulation of sympathetic responses during emotional stimulation in patients with LE, probably due to impaired functioning of the amygdala.

11.
Ann Clin Transl Neurol ; 2(9): 906-19, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26401512

RESUMEN

OBJECTIVE: HIV-associated neurocognitive disorders (HAND) remain a challenge despite combination antiretroviral therapy (cART). Immune cell activation has been implicated to play a major role in the development of HAND. METHODS: In this study, we used multicolor flow cytometry on peripheral blood (PB) and cerebrospinal fluid (CSF) samples to determine the expression of HLA-DR and programmed death-1 (PD-1) on CD4+ and CD8+ T cells in patients with chronic HIV infection. Expression levels were correlated with HI virus load in PB and CSF, classification of HAND and severity of magnetic resonance imaging (MRI) signal abnormalities. RESULTS: In a cohort of 86 HIV patients we found that the grade of neurocognitive impairment and the severity of MRI signal abnormalities correlated with decreasing CD4/CD8-ratios and increased frequencies of HLA-DR expressing CD4+ and CD8+ T cells reaching the highest values in the CSF samples. Importantly, HLA-DR upregulation was still detectable in virologically suppressed HIV patients. Further, T-cell subpopulation analysis of 40 HIV patients showed a significant shift from naïve to effector memory (EM) T cells that was negatively correlated with the grade of neurocognitive impairment in the PB samples. Moreover, PD-1 was significantly increased on CD4+ memory T cells with highest levels on EM T cells in HIV patients with mild or severe neurocognitive alterations. INTERPRETATION: The CD4/CD8 ratio, the proportion of EM to naïve T cells and the immune activation profile of CD4+ and CD8+ T cells in PB and CSF might be useful parameters to monitor the efficacy of cART and to identify HIV patients at risk of further neurocognitive deterioration.

12.
Neurobiol Aging ; 36(1): 81-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25277040

RESUMEN

In Alzheimer's disease, the contribution of inflammation is still controversially discussed. The aim of this study was to identify a particular immune profile in the peripheral blood (PB) and cerebrospinal fluid (CSF) in patients with mild Alzheimer's disease (mAD) and mild cognitive impairment (MCI) and its potential functional relevance and association with neurodegeneration. A total of 88 patients with cognitive decline (54 mAD, 19 MCI, and 15 other dementias) were included in this study and compared with a group of younger (mean age, 31.3 years) and older (mean age, 68.9 years) healthy volunteers. Patients underwent detailed neurologic and neuropsychological examination, magnetic resonance imaging including voxel-based morphometry of gray matter, voxel-based diffusion tensor imaging, and white matter lesion volumetry, and PB and CSF analysis including multiparameter flow cytometry. Multiparameter flow cytometry revealed that proportions of activated HLA-DR positive CD4(+) and CD8(+) T-cells were slightly and significantly increased in the PB of MCI and mAD patients, respectively, when compared with healthy elderly controls but not in patients with other dementias. Although only a slight enhancement of the proportion of activated CD4(+) T-cells was observed in the CSF of both MCI and mAD patients, the proportion of activated CD8(+) T-cells was significantly increased in the CSF of mAD patients when compared with healthy elderly individuals. A slight increase in the proportion of activated CD8(+) T-cells was also observed in the intrathecal compartment of MCI patients. Activation of cytotoxic CD8(+) T-cells was considerably related to AD-typical neuropsychological deficits. Voxel-based regression analysis revealed a significant correlation between CD8(+) T-cell activation and microstructural tissue damage within parahippocampal areas as assessed by diffusion tensor imaging. Taken together, peripheral and intrathecal CD8(+) T-cell activation in mAD was significantly different from other dementias, suggesting a specific adaptive immune response. Lymphocyte activation seems to have a clinical impact because levels of activated CD8(+) T-cells were correlated with clinical and structural markers of AD pathology.


Asunto(s)
Enfermedad de Alzheimer/inmunología , Sangre/inmunología , Linfocitos T CD8-positivos/inmunología , Líquido Cefalorraquídeo/inmunología , Disfunción Cognitiva/inmunología , Activación de Linfocitos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Biomarcadores , Encéfalo/patología , Cognición , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/patología , Disfunción Cognitiva/psicología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
13.
J Neurol Neurosurg Psychiatry ; 86(7): 809-15, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25248366

RESUMEN

OBJECTIVE: Despite refined criteria for behavioural variant frontotemporal dementia (bvFTD), its differentiation from Alzheimer's dementia (AD) remains difficult at early clinical presentation. Apraxia is not considered as a supportive feature for the diagnosis of bvFTD, but for AD. However, only few studies have quantified praxis disturbances in mild disease stages and their specificity for AD compared with bvFTD remains indistinct. We explore apraxia in bvFTD and investigate the differential validity of apraxia screening tests to distinguish between AD, bvFTD and healthy controls (HC). METHODS: We compared composite apraxia scores assessed with standardised neuropsychological screening tests as well as performance in praxis subdomains in patients who fulfil current clinical criteria for AD (N=20), bvFTD (N=20), and in HC (N=20). RESULTS: Composite scores of apraxia screening tests provided high diagnostic accuracy for detecting mild stages of both neurodegenerative disorders compared with HC (sensitivity: 75-95%; specificity: 70-90%). Both patient groups showed pronounced impairments in limb praxis, especially in imitation of hand and finger postures (bvFTD: 71.7%; AD: 55.5%; HC: 86.7%) and pantomime of object use (bvFTD: 88.6%; AD: 81.4%; HC: 97.5%). Beyond that, patients with bvFTD displayed a unique profile of deficits for imitating face postures (bvFTD: 69%; AD: 88%; HC: 95.5%). CONCLUSIONS: Praxis disturbances are important but under-represented diagnostic features in mild stages of AD and bvFTD. Apraxia screening tests are easily applicable diagnostic tools, which may support clinical diagnoses of both neurodegenerative diseases. The analysis of individual apraxia profiles can effectively facilitate differential diagnosis of AD and bvFTD.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Ataxia/etiología , Demencia Frontotemporal/diagnóstico , Anciano , Enfermedad de Alzheimer/fisiopatología , Ataxia/diagnóstico , Diagnóstico Diferencial , Femenino , Demencia Frontotemporal/fisiopatología , Humanos , Masculino , Pruebas Neuropsicológicas , Sensibilidad y Especificidad
14.
J Clin Exp Neuropsychol ; 36(1): 32-42, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24341534

RESUMEN

Rey's Auditory Verbal Learning Test (AVLT) is widely used to evaluate dysfunctional episodic memory. The current study aimed to provide extended age- and gender-specific norms for the German AVLT for individuals older than 50 years. In 690 subjects, a comprehensive medical examination including a structural 3.0-tesla magnetic resonance imaging scan was administered, as well as extensive neuropsychological tests. After controlling for exclusion criteria, 407 subjects were included in the analysis. AVLT performance decreased with age, and women outperformed men. We present age- and gender-specific normative data for the German AVLT from subjects aged between 50 and 70 years.


Asunto(s)
Envejecimiento/fisiología , Aprendizaje/fisiología , Pruebas Neuropsicológicas , Percepción del Habla/fisiología , Factores de Edad , Anciano , Femenino , Alemania/epidemiología , Humanos , Masculino , Memoria Episódica , Recuerdo Mental/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas/estadística & datos numéricos , Reconocimiento en Psicología/fisiología , Valores de Referencia , Factores Sexuales , Aprendizaje Verbal/fisiología
15.
Hum Brain Mapp ; 34(12): 3333-46, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22815223

RESUMEN

Individual differences in executive functioning and brain morphology are considerable. In this study, we investigated their interrelation in a large sample of healthy older individuals. Digit span, trail-making, and Stroop tasks were used to assess different executive subfunctions in 367 nondemented community-dwelling individuals (50-81 years). Task performance was analyzed relative to brain structure using voxel-based morphometry, corrected for age and sex. Improved task performance was associated with increased local gray matter volume in task-specific patterns that showed partial, but not complete overlap with known task-specific functional imaging patterns. While all three tasks showed associations with prefrontal gray matter volume as expected for executive functioning, the strongest overlap between the three tasks was found in insular cortex, suggesting that it has a previously underestimated role for executive functions. The association between the insular cortex and executive functioning was corroborated using stereological region-of-interest measurement of insular volume in a subgroup of 93 subjects. Quantitatively, the volume of the single most strongly related region explained 2.4 ± 1.1% of the variance in executive performance over and above the variance explained by age, which amounted to 7.4 ± 4.1%. The age-independent peak associations between executive performance and gray matter described here occurred in regions that were also strongly affected by age-related gray matter atrophy, consistent with the hypothesis that age-related regional brain volume loss and age-related cognitive changes are linked.


Asunto(s)
Envejecimiento , Mapeo Encefálico , Encéfalo/anatomía & histología , Encéfalo/fisiología , Función Ejecutiva/fisiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Alemania , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Pruebas Neuropsicológicas , Factores Sexuales , Técnicas Estereotáxicas
16.
Neurobiol Aging ; 33(8): 1682-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21684040

RESUMEN

Remembering the location of objects, an integral part of everyday life, is known to decline with advancing age and early in the course of neurodegenerative dementia. Here, we aimed to test if object-location learning and its retention could be modified by noninvasive brain stimulation. In a group of 20 elderly (mean age 62.1 years) right-handed individuals, we applied transcranial direct current stimulation (tDCS; 20 minutes, 1 mA) over the right temporoparietal cortex, while subjects acquired the correct position of buildings on a street map using an associative learning paradigm. Each subject participated in a randomized and balanced order in 1 session of anodal tDCS and 1 session of sham stimulation, in a double-blind design with 2 parallel versions of the task. Outcome measures were learning success at the end of each session, and immediate as well as delayed (1 week) free recall. We found that subjects performed comparably in the learning task in the 2 conditions, but showed improved recall 1 week after learning with anodal tDCS compared with learning with sham stimulation. In conclusion, retention of object-location learning in the elderly may be modulated by noninvasive brain stimulation, a finding of potential relevance not only for normal aging but also for memory deficits in pathological aging.


Asunto(s)
Aprendizaje/fisiología , Reconocimiento Visual de Modelos/fisiología , Percepción Espacial/fisiología , Conducta Espacial/fisiología , Análisis y Desempeño de Tareas , Estimulación Magnética Transcraneal/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
17.
Pain ; 152(4): 904-911, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21296501

RESUMEN

Regional decreases in grey matter volume as detected by magnetic resonance imaging-based volumetry have been reported in several clinical chronic pain cohorts. Here, we used voxel-based morphometry in a nonclinical cohort to investigate whether grey matter alterations also occur in older individuals (aged 40-85 years) from the general population. Based on self-report of pain, we identified 31 pain-free controls, 45 subjects with ongoing pain (low back pain, headache, or lower extremity joint pain) who had at least moderate pain on more than 3 days/month, and 29 individuals with past pain (stopped for >12 months). Relative to controls, the ongoing pain group showed regional grey matter volume decreases, predominantly in cingulate, prefrontal, and motor/premotor regions. No grey matter volume decreases were found in the group with pain that had stopped for >12 months. These results show that pain-related grey matter volume decreases are present in individuals from the general population. The lack of morphometric anomalies in subjects with past pain supports recent evidence suggesting that pain-related grey matter changes are reversible after cessation of pain.


Asunto(s)
Mapeo Encefálico , Encéfalo/patología , Dolor/patología , Anciano , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Dolor/clasificación , Dimensión del Dolor , Autoinforme
18.
Epilepsia ; 52(3): 636-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21275981

RESUMEN

Presurgical determination of language lateralization is important for planning and outcome estimation of neurosurgical interventions in patients with drug-refractory epilepsy. Functional transcranial Doppler sonography (fTCD) provides an established measure for language lateralization using the temporal bone windows for continuous recording of the cerebral blood flow velocity (CBFV) in both middle cerebral arteries (MCAs). However, because of insufficient temporal bone windows, fTCD cannot be applied properly in every patient. Here, we established stable and sufficient CBFV signals in both MCAs using continuous intravenous application of echo-enhancing agent SonoVue in 7 of 10 patients with poor temporal bone windows and were thus able to determine language lateralization. We conclude that the application of SonoVue can solve one principal disadvantage of fTCD and improves the applicability of the technique as a presurgical functional language lateralization procedure.


Asunto(s)
Medios de Contraste/administración & dosificación , Dominancia Cerebral/fisiología , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Aumento de la Imagen , Lenguaje , Arteria Cerebral Media/diagnóstico por imagen , Fosfolípidos , Hexafluoruro de Azufre , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Estudios de Factibilidad , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
19.
Age (Dordr) ; 33(1): 101-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20589439

RESUMEN

Verbal comprehension is critical to the success of medical counseling. Here, we tested how age and vascular risk factors affect the ability to understand complex instructions. Verbal comprehension, cognitive functions, and vascular risk factors were assessed in 39 mid- and 38 late-life community-dwelling individuals (48 to 59 years and >59 years of age, respectively). To test for verbal comprehension, we used a modified version of the Token Test (TT). In midlife individuals, education (ß = 0.572, p < 0.05) was the only predictor for extended-TT performance. In late-life individuals, age (ß = -1.015, p < 0.001) and body mass index (ß = -0.651, p = 0.003) were significantly correlated with extended-TT performance and explained 50% of the variance in extended-TT performance (adjusted R (2) = 0.503). This relation is only partly explained by conventional neuropsychological measures as the ones used in our test battery. These results indicate that aging and overweight impair comprehension of complex instructions. Therefore, medical counseling appropriate for midlife individuals may be less successful in elderly people and particularly in those with metabolic disturbances.


Asunto(s)
Envejecimiento/fisiología , Enfermedades Cardiovasculares/complicaciones , Cognición/fisiología , Comprensión/fisiología , Factores de Edad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
20.
Mov Disord ; 25(12): 1986-92, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20669295

RESUMEN

Hereditary spastic paraplegias (HSP) are genetically and clinically heterogeneous neurodegenerative disorders. Most MR studies on HSP include very heterogeneous samples of patients, and findings were inconsistent. Here, we examined six patients with pure HSP and SPG4 mutations by clinical evaluation, detailed neuropsychological testing, and neuroimaging analyses, including conventional MRI, diffusion tensor imaging (DTI), and brain volumetry. Differences of voxel-wise statistics and ROI-based analysis of DTI data between patients and 32 healthy volunteers were evaluated. Although conventional MRI and brain volumetry were normal, DTI revealed widespread disturbance of white matter (WM) integrity (P < 0.001), mainly affecting the corticospinal tract. With longer disease duration, frontal regions were also involved. The WM changes were also present in subclinical subjects harbouring the pathogenic mutation. These subtle WM abnormalities have functional relevance because they correlated with clinical symptoms. Thus, early alterations of nerve fibres, which can be detected by DTI, might serve as a biological marker in HSP, in particular with respect to future longitudinal studies.


Asunto(s)
Encéfalo/patología , Fibras Nerviosas Mielínicas/patología , Tractos Piramidales/patología , Paraplejía Espástica Hereditaria/patología , Adulto , Anciano , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
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