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1.
Clin Genet ; 105(3): 335-339, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38041579

RESUMO

Facioscapulohumeral dystrophy (FSHD) is an autosomal dominant disease, although 10%-30% of cases are sporadic. However, this percentage may include truly de novo patients (carrying a reduced D4Z4 allele that is not present in either of the parents) and patients with apparently sporadic disease resulting from mosaicism, non-penetrance, or complex genetic situations in either patients or parents. In this study, we characterized the D4Z4 Reduced Alleles (DRA) and evaluated the frequency of truly de novo cases in FSHD1 in a cohort of DNA samples received consecutively for FSHD-diagnostic from 100 Italian families. The D4Z4 testing revealed that 60 families reported a DRA compatible with FSHD1 (1-10 RU). The DRA co-segregated with the disease in most cases. Five families with truly de novo cases were identified, suggesting that this condition may be slightly lower (8%) than previously reported. In addition, D4Z4 characterization in the investigated families showed 4% of mosaic cases and 2% with translocations. This study further highlighted the importance of performing family studies for clarifying apparently sporadic FSHD cases, with significant implications for genetic counseling, diagnosis, clinical management, and procreative choices for patients and families.


Assuntos
Distrofia Muscular Facioescapuloumeral , Humanos , Distrofia Muscular Facioescapuloumeral/diagnóstico , Distrofia Muscular Facioescapuloumeral/genética , Alelos , Mosaicismo , Itália/epidemiologia , Cromossomos Humanos Par 4/genética
2.
Ann Neurol ; 92(3): 464-475, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35713198

RESUMO

OBJECTIVE: In Alzheimer disease (AD) animal models, synaptic dysfunction has recently been linked to a disorder of high-frequency neuronal activity. In patients, a clear relation between AD and oscillatory activity remains elusive. Here, we attempt to shed light on this relation by using a novel approach combining transcranial magnetic stimulation and electroencephalography (TMS-EEG) to probe oscillatory activity in specific hubs of the frontoparietal network in a sample of 60 mild-to-moderate AD patients. METHODS: Sixty mild-to-moderate AD patients and 21 age-matched healthy volunteers (HVs) underwent 3 TMS-EEG sessions to assess cortical oscillations over the left dorsolateral prefrontal cortex, the precuneus, and the left posterior parietal cortex. To investigate the relations between oscillatory activity, cortical plasticity, and cognitive decline, AD patients underwent a TMS-based neurophysiological characterization and a cognitive evaluation at baseline. The latter was repeated after 24 weeks to monitor clinical evolution. RESULTS: AD patients showed a significant reduction of frontal gamma activity as compared to age-matched HVs. In addition, AD patients with a more prominent decrease of frontal gamma activity showed a stronger impairment of long-term potentiation-like plasticity and a more pronounced cognitive decline at subsequent follow-up evaluation at 24 weeks. INTERPRETATION: Our data provide novel evidence that frontal lobe gamma activity is dampened in AD patients. The current results point to the TMS-EEG approach as a promising technique to measure individual frontal gamma activity in patients with AD. This index could represent a useful biomarker to predict disease progression and to evaluate response to novel pharmacological therapies. ANN NEUROL 2022;92:464-475.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Animais , Eletroencefalografia/métodos , Lobo Frontal , Humanos , Estimulação Magnética Transcraniana/métodos
3.
Electrophoresis ; 44(19-20): 1588-1594, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37565369

RESUMO

The alteration of epigenetic modifications, including DNA methylation, can contribute to the etiopathogenesis and progression of many diseases. Among them, facioscapulohumeral dystrophy (FSHD) is a muscular disorder characterized by the loss of repressive epigenetic features affecting the D4Z4 locus (4q35). As a consequence, these alterations are responsible for DNA hypomethylation and a transcriptional-active chromatin conformation change that, in turn, lead to the aberrant expression of DUX4 in muscle cells. In the present study, methylation levels of 29 CpG sites of the DR1 region (within each repeat unit of the D4Z4 macrosatellite) were assessed on 335 subjects by employing primers designed for enhancing the performance of the assay. First, the DR1 original primers were optimized by adding M13 oligonucleotide tails. Moreover, the DR1 reverse primer was replaced with a degenerate one. As a result, the protocol optimization allowed a better sequencing resolution and a more accurate evaluation of DR1 methylation levels. Moreover, the assessment of the repeatability of measurements proved the reliability and robustness of the assay. The optimized protocol emerges as an excellent method to detect methylation levels compatible with FSHD.

4.
Brain ; 145(11): 3776-3786, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36281767

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is emerging as a non-invasive therapeutic strategy in the battle against Alzheimer's disease. Alzheimer's disease patients primarily show alterations of the default mode network for which the precuneus is a key node. Here, we hypothesized that targeting the precuneus with TMS represents a promising strategy to slow down cognitive and functional decline in Alzheimer's disease patients. We performed a randomized, double-blind, sham-controlled, phase 2, 24-week trial to determine the safety and efficacy of precuneus stimulation in patients with mild-to-moderate Alzheimer's disease. Fifty Alzheimer's disease patients were randomly assigned in a 1:1 ratio to either receive precuneus or sham rTMS (mean age 73.7 years; 52% female). The trial included a 24-week treatment, with a 2-week intensive course in which rTMS (or sham) was applied daily five times per week, followed by a 22-week maintenance phase in which stimulation was applied once weekly. The Clinical Dementia Rating Scale-Sum of Boxes was selected as the primary outcome measure, in which post-treatment scores were compared to baseline. Secondary outcomes included score changes in the Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental State Examination and Alzheimer's Disease Cooperative Study-Activities of Daily Living scale. Moreover, single-pulse TMS in combination with EEG was used to assess neurophysiological changes in precuneus cortical excitability and oscillatory activity. Our findings show that patients that received precuneus repetitive magnetic stimulation presented a stable performance of the Clinical Dementia Rating Scale-Sum of Boxes score, whereas patients treated with sham showed a worsening of their score. Compared with the sham stimulation, patients in the precuneus stimulation group also showed also significantly better performances for the secondary outcome measures, including the Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental State Examination and Alzheimer's Disease Cooperative Study-Activities of Daily Living scale. Neurophysiological results showed that precuneus cortical excitability remained unchanged after 24 weeks in the precuneus stimulation group, whereas it was significantly reduced in the sham group. Finally, we found an enhancement of local gamma oscillations in the group treated with precuneus stimulation but not in patients treated with sham. We conclude that 24 weeks of precuneus rTMS may slow down cognitive and functional decline in Alzheimer's disease. Repetitive TMS targeting the default mode network could represent a novel therapeutic approach in Alzheimer's disease patients.


Assuntos
Doença de Alzheimer , Humanos , Feminino , Idoso , Masculino , Atividades Cotidianas , Estimulação Magnética Transcraniana/métodos , Lobo Parietal , Fenômenos Magnéticos
5.
Neurol Sci ; 44(3): 1109-1118, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36542204

RESUMO

BACKGROUND: At the moment, the possible options for the management of cognitive dysfunctions in patients with MS (pMS) are pharmacological interventions, cognitive rehabilitation (CR), and physical exercise. However, worldwide, multimodal programs are infrequently applied in pMS and CR is not easily accessible through the National Health System as MR. OBJECTIVE: The aim of the study is to explore if the combination of motor and cognitive rehabilitation may favor better outcomes on cognitive efficiency compared to separate trainings. METHODS: Forty-eight pMS were submitted to detailed neuropsychological and motor assessments, before (T0) and after (T1) having performed one of three rehabilitation conditions (two cognitive trainings/week-Reha1; one cognitive and one motor training/week-Reha2; two motor trainings/week-Reha3, for 12 weeks); they were randomly assigned to one condition or another. The CR was focused on memory functioning and performed with the Rehacom program. RESULTS: No significant differences in age, sex, education, and disease course were found between the three groups (sig. > .05). Reha1 patients increased only their cognitive performance, and Reha3 only increased their motor performance, while Reha2 increased both cognitive and motor performances. This benefit was also confirmed by the cognitive efficiency expressed by the Cognitive Impairment Index. CONCLUSIONS: These data confirm that to include cognitive training within rehabilitation programs may induce important benefits in pMS. Furthermore, pMS seem to benefit from a combined approach (cognitive and motor) more than from CR and motor rehabilitation separately (ClinicalTrial.gov ID: NCT05462678; 14 July 2022, retrospectively registered).


Assuntos
Disfunção Cognitiva , Humanos , Cognição/fisiologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/reabilitação , Terapia por Exercício , Memória/fisiologia , Resultado do Tratamento
6.
Int J Mol Sci ; 24(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37373323

RESUMO

Since the spinal cord has traditionally been considered a bundle of long fibers connecting the brain to all parts of the body, the study of its role has long been limited to peripheral sensory and motor control. However, in recent years, new studies have challenged this view pointing to the spinal cord's involvement not only in the acquisition and maintenance of new motor skills but also in the modulation of motor and cognitive functions dependent on cortical motor regions. Indeed, several reports to date, which have combined neurophysiological techniques with transpinal direct current stimulation (tsDCS), have shown that tsDCS is effective in promoting local and cortical neuroplasticity changes in animals and humans through the activation of ascending corticospinal pathways that modulate the sensorimotor cortical networks. The aim of this paper is first to report the most prominent tsDCS studies on neuroplasticity and its influence at the cortical level. Then, a comprehensive review of tsDCS literature on motor improvement in animals and healthy subjects and on motor and cognitive recovery in post-stroke populations is presented. We believe that these findings might have an important impact in the future making tsDCS a potential suitable adjunctive approach for post-stroke recovery.


Assuntos
Córtex Motor , Acidente Vascular Cerebral , Animais , Humanos , Potencial Evocado Motor/fisiologia , Medula Espinal/fisiologia , Encéfalo , Acidente Vascular Cerebral/terapia , Córtex Motor/fisiologia
7.
Eur J Neurol ; 29(2): 505-514, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34687120

RESUMO

BACKGROUND AND PURPOSE: Difficulties in emotion processing and social cognition identified in multiple sclerosis (MS) patients have a potential impact on their adaptation to the social environment. We aimed to explore the neural correlates of emotion recognition in MS and possible differences between relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS) patients by the Reading the Mind in the Eyes test (RMEt). METHODS: A total of 43 MS patients (27 RRMS, 16 SPMS) and 25 matched healthy controls (HC) underwent clinical assessments, RMEt, and a high-resolution T1-weighted 3-T magnetic resonance imaging (MRI) scan. The number of correct answers on the RMEt was compared between groups. T1-weighted volumes were processed according to an optimized voxel-based morphometry (VBM) protocol to obtain gray matter (GM) maps. Voxelwise analyses were run to assess potential associations between RMEt performance and regional GM volumes. RESULTS: Taken altogether, MS patients reported significantly lower performance on the RMEt compared to HC. When dividing the patients into those with RRMS and those with SPMS, only the latter group was found to perform significantly worse than HC on the RMEt. VBM analysis revealed significant association between RMEt scores and GM volumes in several cortical (temporoparieto-occipital cortex) and subcortical (hippocampus, parahippocampus, and basal ganglia) brain regions, and in the cerebellum in SPMS patients only. CONCLUSIONS: Results suggest that, in addition to other clinical differences between RRMS and SPMS, the ability to recognize others' emotional states may be affected in SPMS more significantly than RRMS patients. This is supported by both behavioral and MRI data.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Emoções , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/complicações , Esclerose Múltipla Crônica Progressiva/complicações , Esclerose Múltipla Recidivante-Remitente/complicações
8.
Int J Mol Sci ; 23(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35269707

RESUMO

Precision medicine emphasizes fine-grained diagnostics, taking individual variability into account to enhance treatment effectiveness. Parkinson's disease (PD) heterogeneity among individuals proves the existence of disease subtypes, so subgrouping patients is vital for better understanding disease mechanisms and designing precise treatment. The purpose of this study was to identify PD subtypes using RNA-Seq data in a combined pipeline including unsupervised machine learning, bioinformatics, and network analysis. Two hundred and ten post mortem brain RNA-Seq samples from PD (n = 115) and normal controls (NCs, n = 95) were obtained with systematic data retrieval following PRISMA statements and a fully data-driven clustering pipeline was performed to identify PD subtypes. Bioinformatics and network analyses were performed to characterize the disease mechanisms of the identified PD subtypes and to identify target genes for drug repurposing. Two PD clusters were identified and 42 DEGs were found (p adjusted ≤ 0.01). PD clusters had significantly different gene network structures (p < 0.0001) and phenotype-specific disease mechanisms, highlighting the differential involvement of the Wnt/ß-catenin pathway regulating adult neurogenesis. NEUROD1 was identified as a key regulator of gene networks and ISX9 and PD98059 were identified as NEUROD1-interacting compounds with disease-modifying potential, reducing the effects of dopaminergic neurodegeneration. This hybrid data analysis approach could enable precision medicine applications by providing insights for the identification and characterization of pathological subtypes. This workflow has proven useful on PD brain RNA-Seq, but its application to other neurodegenerative diseases is encouraged.


Assuntos
Doença de Parkinson , Encéfalo/metabolismo , Redes Reguladoras de Genes , Humanos , Aprendizado de Máquina , Doença de Parkinson/metabolismo , RNA-Seq
9.
Hum Brain Mapp ; 42(5): 1343-1358, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33439537

RESUMO

Interhemispheric interactions in stroke patients are frequently characterized by abnormalities, in terms of balance and inhibition. Previous results showed an impressive variability, mostly given to the instability of motor-evoked potentials when evoked from the affected hemisphere. We aim to find reliable interhemispheric measures in stroke patients with a not-evocable motor-evoked potential from the affected hemisphere, by combining transcranial magnetic stimulation (TMS) and electroencephalography. Ninteen stroke patients (seven females; 61.26 ± 9.8 years) were studied for 6 months after a first-ever stroke in the middle cerebral artery territory. Patients underwent four evaluations: clinical, cortical, corticospinal, and structural. To test the reliability of our measures, the evaluations were repeated after 3 weeks. To test the sensitivity, 14 age-matched healthy controls were compared to stroke patients. In stroke patients, stimulation of the affected hemisphere did not result in any inhibition onto the unaffected. The stimulation of the unaffected hemisphere revealed a preservation of the inhibition mechanism onto the affected. This resulted in a remarkable interhemispheric imbalance, whereas this mechanism was steadily symmetric in healthy controls. This result was stable when cortical evaluation was repeated after 3 weeks. Importantly, patients with a better recovery of the affected hand strength were the ones with a more stable interhemispheric balance. Finally, we found an association between microstructural integrity of callosal fibers, suppression of interhemispheric TMS-evoked activity and interhemispheric connectivity. We provide direct and sensitive cortical measures of interhemispheric imbalance in stroke patients. These measures offer a reliable means of distinguishing healthy and pathological interhemispheric dynamics.


Assuntos
Córtex Cerebral/fisiopatologia , Eletroencefalografia , Potencial Evocado Motor/fisiologia , Mãos/fisiopatologia , Tratos Piramidais/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Estimulação Magnética Transcraniana , Adulto , Idoso , Conectoma , Feminino , Humanos , Infarto da Artéria Cerebral Média/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
10.
J Neural Transm (Vienna) ; 128(2): 273-277, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33068177

RESUMO

Safinamide is a monoamine-oxidase-B inhibitor with peculiar features. At the dose of 100 mg/day, safinamide stimulates dopaminergic transmission and reduces glutamatergic transmission. Here, we investigated the effects of safinamide 100 mg on executive functions at the end of levodopa dose in fluctuating Parkinson's disease (PD) patients. Thirty-two fluctuating PD patients were submitted at baseline (V1) to the UPDRS-III, the Frontal Assessment Battery (FAB) and the Stroop-Word-Color-Test (SWCT) at the end of levodopa dose. Safinamide was then added to the original therapy. After 12 weeks of treatment, patients underwent the final visit (V2), including the UPDRS-III, the FAB and the SWCT with the same daily time schedule as V1. Treatment with safinamide was associated with significant increases of the total FAB score, SWCT-interference time score and UPDRS-III score. Within FAB subdomains, add-on with safinamide significantly increased motor programming and increased mental flexibility and inhibitory control scores. The results of this exploratory study show that add-on with safinamide improves executive functions at the end of levodopa dose in fluctuating PD patients. In particular, attention and inhibition of cognitive interference were significantly ameliorated by add-on with safinamide, suggesting increased modulatory performances of prefrontal cortical pathways. If confirmed by future research on larger cohorts and under controlled conditions, the present results may represent the basis for a novel indication for the use of safinamide in fluctuating PD patients.


Assuntos
Doença de Parkinson , Alanina/análogos & derivados , Antiparkinsonianos/uso terapêutico , Benzilaminas , Função Executiva , Humanos , Levodopa , Doença de Parkinson/tratamento farmacológico
11.
J Geriatr Psychiatry Neurol ; 34(6): 582-593, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32734799

RESUMO

The aim of the current study was to test the accuracy of practice effects, that is, improvement in test performance due to repeated neuropsychological evaluations, in identifying patients with amnestic mild cognitive impairment (a-MCI) at greater risk of conversion to Alzheimer disease (AD). For this purpose, we conducted a longitudinal study of 54 patients diagnosed with a-MCI at the first assessment and followed-up for 4 years. During this time, 18 patients converted to AD. Baseline and 6- to 12-month follow-up performances on a large set of neuropsychological tests were analyzed to determine their diagnostic ability to predict later conversion to dementia. Results demonstrate that a lack of practice effects on episodic memory tests is an accurate prognostic indicator of late conversion to AD in a-MCI patients. In fact, even though the performance of both groups was substantially comparable at the baseline evaluation, stable a-MCI patients greatly improved their memory performance at retest after 6 to 12 months; instead, scores of converter a-MCI remained stable or decreased passing from baseline to follow-up. Standardized z-change scores on memory tasks, which were computed as a reliable measure of performance change, classified group membership with very good overall accuracy, which was higher than the classification of converter and stable a-MCIs provided by baseline or follow-up scores. We hypothesize that the lack of practice effects on memory tasks mirrors the early involvement of medial temporal lobe areas in converter a-MCI that are fundamental for the consolidation of new memory traces.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Progressão da Doença , Humanos , Estudos Longitudinais , Testes Neuropsicológicos
12.
Acta Neurol Scand ; 144(4): 383-393, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33999426

RESUMO

OBJECTIVES: Working memory (WM) for verbal and visual material may be affected early in individuals with mild cognitive impairment (MCI). Verbal and visuospatial span tasks, that is neuropsychological procedures commonly used for the clinical assessment of WM, have been scarcely investigated in these patients. Therefore, this study was aimed at evaluating whether performance on tests of verbal and visual-spatial span (which rely to different extents on distinct components of the WM system) is differently sensitive to the presence of MCI and, in particular, of a preclinical AD condition in patients with MCI. MATERIALS & METHODS: 99 patients with amnesic MCI were given the Digit Span Forward (DSF) and Digit Span Backward (DSB) tests and the Corsi span task (CS) at baseline and were followed up for two years. 32 MCI patients converted to Alzheimer's disease (MCIc), but 67 patients did not deteriorate to meet the criteria for AD (MCIs). RESULTS: Results showed that although performance on DSF did not differ between groups, performance on DSB and CS and ratio indexes indicative of a performance decline passing from DSF to DSB and from DSF to CS significantly discriminated between a group of matched healthy controls and the overall group of MCI patients. Moreover, the ratio indexes significantly discriminated between MCIc and MCIs individuals. CONCLUSIONS: These data are consistent with the hypothesis that individuals with MCI, particularly those destined to convert to AD, are affected by reduced central executive resources even though the phonological loop is still functioning normally.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/complicações , Humanos , Memória de Curto Prazo , Testes Neuropsicológicos , Memória Espacial
13.
Exp Aging Res ; 47(1): 1-20, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33107393

RESUMO

How prospective memory (PM) weakens with increasing age has been largely debated. We hypothesized that automatic and strategic PM processes, respectively mediated by focal and non-focal cues, are differently affected by aging, even starting from 50-60 years of age. We investigated this issue using a 2 × 2 design in which focal and non-focal experimental conditions were created by varying the conjoint nature of the ongoing task (lexical decision vs. syllable matching tasks) and the PM cue (words vs. syllables). In the whole-brain analysis we found that the left inferior frontal gyrus and the middle cingulate cortex were more activated when young compared to older individuals performed a PM task; moreover, the anterior cingulate cortex was selectively activated during non-focal PM when the cues were words. In a region-of-interest analysis we observed that the medial and the lateral portions of the rostral prefrontal cortex were associated with the focal and non-focal conditions respectively, more in young than in older adults. Our findings provide evidence in support of early age-related differences in automatic/strategic PM functioning.


Assuntos
Sinais (Psicologia) , Memória Episódica , Idoso , Envelhecimento , Humanos , Imageamento por Ressonância Magnética , Tempo de Reação
14.
Medicina (Kaunas) ; 57(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34833389

RESUMO

Backround and Objectives: It is widely agreed that patients suffering from Alzheimer's disease (AD) and patients suffering from semantic dementia (SD) might fail clinically administered semantic tasks due to a different combination of underlying cognitive deficits: namely, degraded semantic representations in SD and degraded representations plus executive control deficit in AD. However, no easy administrable test or test battery for differentiating the semantic impairment profile in these populations has been devised yet. Materials and Methods: In this study, we propose a new easy administrable task based on a free association procedure (F-Assoc) to be used in conjunction with category fluency (Cat-Fl) and letter fluency (Lett-Fl) for quantifying pure representational and pure control deficits, thus teasing apart the semantic profile of SD and AD patients. Results: In a sample of 10 AD and 10 SD subjects, matched for disease severity, we show that indices of asymmetric performance contrasting F-Assoc and each of the two verbal fluency tasks yield a clearly distinguishable discrepancy pattern across SD and AD. We also provide empirical support for the validity of an asymmetry measure contrasting F-Assoc and Cat-FL as an index of control impairment. Conclusions: The present study suggests that the free association procedure provides a pure measure of degradation of semantic representations avoiding the confound of possible concomitant executive deficits.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doença de Alzheimer/diagnóstico , Associação Livre , Demência Frontotemporal/diagnóstico , Humanos , Testes Neuropsicológicos , Semântica
15.
Neuroimage ; 208: 116424, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31794855

RESUMO

The cerebellum is strongly implicated in learning new motor skills. Theta burst stimulation (TBS), a form of repetitive transcranial magnetic stimulation, can be used to influence cerebellar activity. Our aim was to explore the potential of cerebellar TBS in modulating visuo-motor adaptation, a form of motor learning, in young healthy subjects. Cerebellar TBS was applied immediately before the learning phase of a visuo-motor adaptation task (VAT), in two different experiments. Firstly, we evaluated the behavioral effects of continuous (cTBS), intermittent (iTBS) or sham TBS on the learning, re-adaptation and de-adaptation phases of VAT. Subsequently, we investigated the changes induced by iTBS or sham TBS on motor cortical activity related to each phase of VAT, as measured by concomitant TMS/EEG recordings. We found that cerebellar TBS induced a robust bidirectional modulation of the VAT performance. More specifically, cerebellar iTBS accelerated visuo-motor adaptation, by speeding up error reduction in response to a novel perturbation. This gain of function was still maintained when the novel acquired motor plan was tested during a subsequent phase of re-adaptation. On the other hand, cerebellar cTBS induced the opposite effect, slowing the rate of error reduction in both learning and re-adaptation phases. Additionally, TMS/EEG recordings showed that cerebellar iTBS induced specific changes of cortical activity in the interconnected motor networks. The improved performance was accompanied by an increase of TMS-evoked cortical activity and a generalized desynchronization of TMS-evoked cortical oscillations. Taken together, our behavioral and neurophysiological findings provide the first-time multimodal evidence of the potential efficacy of cerebellar TBS in improving motor learning, by promoting successful cerebellar-cortical reorganization.


Assuntos
Adaptação Fisiológica/fisiologia , Ondas Encefálicas/fisiologia , Cerebelo/fisiologia , Sincronização Cortical/fisiologia , Aprendizagem/fisiologia , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Estimulação Magnética Transcraniana , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
16.
Cerebellum ; 19(6): 897-901, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32681455

RESUMO

Difficulties in gait and balance disorders are among the most common mobility limitations in multiple sclerosis (MS), mainly due to a damage of cerebellar circuits. Moreover, the cerebellum plays a critical role in promoting new motor tasks, which is an essential function for neurorehabilitation. In this study, we investigated the effects of cerebellar intermittent theta burst stimulation (c-iTBS), a high-frequency rTMS protocol able to increase cerebellar activity, on gait and balance in a sample of 20 hospitalized participants with MS, undergoing vestibular rehabilitation (VR), an exercise-based program primarily designed to reduce vertigo and dizziness, gaze instability, and/or imbalance and falls in MS. Patients were assigned to receive either c-iTBS or sham iTBS before being treated with VR during 2 weeks. VR consisted of two types of training: gaze stability and postural stability exercises. The primary outcome measure was the change from baseline in the Tinetti Balance and Gait scale (TBG). The secondary outcome measures were changes from baseline in Berg Balance Scale (BBS), Fatigue Severity Scale (FSS), Two Minute Walking Test (2MWT), and Timed 25-ft walk test (T25FW) scales. MS patients treated with c-iTBS-VR showed a significant improvement in the TBG as compared to patients treated with sham iTBS-VR. Moreover, MS patients in the c-iTBS groups showed better performances in the vestibular-ocular reflex exercises. Combined c-iTBS and VR improves gait and balance abilities more than standard VR treatment in MS patients with a high level of disability.


Assuntos
Cerebelo/fisiologia , Marcha/fisiologia , Esclerose Múltipla/reabilitação , Equilíbrio Postural/fisiologia , Ritmo Teta/fisiologia , Estimulação Magnética Transcraniana/métodos , Vestíbulo do Labirinto/fisiologia , Adulto , Método Duplo-Cego , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/fisiopatologia
17.
Brain Topogr ; 33(5): 613-617, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32564167

RESUMO

Although the cerebellum is not among the most renowned brain structures affected in Alzheimer`s disease (AD), recent evidence suggest that it undergoes degenerative changes during the course of the disease. A main neurophysiological feature of AD patients is the remarkable impairment of long term potentiation (LTP)-like cortical plasticity assessed in the primary motor cortex (M1) using theta burst stimulation (TBS) protocols. In healthy conditions, continuous (cTBS) and intermittent TBS (iTBS) of the cerebellum induce respectively long term depression (LTD)-like and LTP-like after effects in the contralateral M1. Here we aimed at examining the effects of cerebellar TBS on contralateral M1 excitability in a sample of 15 AD patients and 12 healthy age matched controls (HS). Motor evoked potentials (MEPs) were obtained in the contralateral M1 before and after cerebellar cTBS and iTBS protocols. As compared to HS, AD patients showed an impairment of LTP-like cortical plasticity mechanisms following cerebellar iTBS. No difference was observed for the cTBS protocol, in which both populations exhibited the expected LTD-like after effect. This study shows that mechanisms of cerebellar-cortical plasticity are impaired in AD. Given its role in high order cognitive functions, new potential therapeutic strategies could be built up in the future to modulate neural activity in the cerebellum in AD.


Assuntos
Doença de Alzheimer , Cerebelo , Córtex Motor , Estimulação Magnética Transcraniana , Doença de Alzheimer/terapia , Cerebelo/fisiologia , Potencial Evocado Motor , Humanos , Plasticidade Neuronal , Ritmo Teta
18.
Neurocase ; 25(1-2): 1-9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30931814

RESUMO

Thalamo-cortical connectivity was characterised in a patient with bilateral infarct of the thalami, without evidence of cognitive deficits in everyday life. Patient underwent social and emotional tests, Iowa Gambling Task (IGT), with and without concomitant heart rate variability (HRV) recording and at 3T-MRI to assess thalamo-cortical connectivity. Patient showed impairment at the IGT, in somatic marker, in emotions and theory of mind. MRI documented a bilateral damage of the centromedian-parafascicular complex. Patient's thalamic lesions disconnected brain areas involved in decision-making and autonomic regulation, affecting the somatic marker and resulting in the neuropsychological deficit exhibited by L.C.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Infarto Encefálico , Tomada de Decisões/fisiologia , Núcleos Intralaminares do Tálamo , Córtex Pré-Frontal , Percepção Social , Adulto , Infarto Encefálico/patologia , Infarto Encefálico/fisiopatologia , Humanos , Núcleos Intralaminares do Tálamo/patologia , Núcleos Intralaminares do Tálamo/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia
19.
Neurol Sci ; 40(9): 1759-1774, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31049790

RESUMO

AIM: The objective of the present review was to systematically characterize the types of cognitive impairment that are found in different non-brain types of cancer as measured by objective and validated tests, and also to further examine depression and cognitive function in cancer patients and explore their available rehabilitation treatments. RESULTS: A total of 29 articles were reviewed. Most of these studies suggest that chemotherapy as well as the combination of chemotherapy and hormonal therapy can influence cognition in different types of cancer patients. Breast cancer patients appear to be the most affected in neuropsychological function, specifically in terms of cognitive impairment and reduced quality of life, as compared to other non-brain solid tumours. Overall, the most impaired functions were verbal ability, memory, executive function, and motor speed. CONCLUSION: Chemotherapy-related cognitive dysfunction remains under-recognized and undertreated. The various studies reported differing and non-homogenous findings with mixed results, obtained by self-reporting and web-assisted assessment, with other confounding factors such as age and depression during both cancer diagnosis and treatment. An objective neuropsychological assessment is fundamental to avoid underestimation of the extent of chemobrain. Self-reported and web-assisted assessment may ultimately result in confusion between the neuropsychological signs of chemobrain versus those of depression.


Assuntos
Antineoplásicos/efeitos adversos , Disfunção Cognitiva , Transtorno Depressivo , Neoplasias/terapia , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/reabilitação , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/etiologia , Transtorno Depressivo/terapia , Humanos
20.
J Cogn Neurosci ; 30(2): 188-199, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29064340

RESUMO

Although the role of the cerebellum in motor function is well recognized, its involvement in the lexical domain remains to be further elucidated. Indeed, it has not yet been clarified whether the cerebellum is a language structure per se or whether it contributes to language processing when other cognitive components (e.g., cognitive effort, working memory) are required by the language task. Neuromodulation studies on healthy participants have suggested that cerebellar transcranial direct current stimulation (tDCS) is a valuable tool to modulate cognitive functions. However, so far, only a single case study has investigated whether cerebellar stimulation enhances language recovery in aphasic individuals. In a randomized, crossover, double-blind design, we explored the effect of cerebellar tDCS coupled with language treatment for verb improvement in 12 aphasic individuals. Each participant received cerebellar tDCS (20 min, 2 mA) in four experimental conditions: (1) right cathodal and (2) sham stimulation during a verb generation task and (3) right cathodal and (4) sham stimulation during a verb naming task. Each experimental condition was run in five consecutive daily sessions over 4 weeks. At the end of treatment, a significant improvement was found after cathodal stimulation only in the verb generation task. No significant differences were present for verb naming among the two conditions. We hypothesize that cerebellar tDCS is a viable tool for recovery from aphasia but only when the language task, such as verb generation, also demands the activation of nonlinguistic strategies.


Assuntos
Afasia/etiologia , Afasia/terapia , Cerebelo , Linguística , Acidente Vascular Cerebral/complicações , Estimulação Transcraniana por Corrente Contínua , Idoso , Afasia/diagnóstico por imagem , Afasia/fisiopatologia , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral , Resultado do Tratamento
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