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1.
Prog Brain Res ; 287: 217-245, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39097354

RESUMEN

Empathy is a fundamental social ability that allows humans to infer others' emotions and intentions. Empathy is thought to be rooted in bodily sensations coming from the autonomic nervous system. In parallel, the functionality and perceptions coming from the autonomic nervous system could be improved by practicing activities that involve mind-body interactions, such as meditation. Furthermore, perceptions from the autonomic nervous system are thought to be important in the embodiment of abstract concepts. Consequently, in the current study, we collected data online from 581 participants and explored the associations between levels of empathy and (1) the practice of meditation, music, and sports; (2) the impact of self-report measures on bodily awareness and reactivity; and (3) the embodiment of abstract concepts in interoception. In line with previous studies, Meditators were found to have higher empathy scores than Non-Meditators. In addition, lower levels of autonomic reactivity in organs above the diaphragm were associated with higher empathy. Finally, we also observed that empathy was positively associated with interoceptive components of abstract concepts in those participants with high autonomic reactivity. Taken together, the results suggest that meditation practice and having low autonomic reactivity are associated with empathy, arguably through the downregulation of autonomic responses. Implications for mind-body interaction in meditation and its role in promoting empathy are discussed.


Asunto(s)
Sistema Nervioso Autónomo , Empatía , Interocepción , Meditación , Humanos , Empatía/fisiología , Masculino , Femenino , Adulto , Sistema Nervioso Autónomo/fisiología , Interocepción/fisiología , Adulto Joven , Concienciación/fisiología , Persona de Mediana Edad , Emociones/fisiología
2.
Clin Neurophysiol ; 156: 19-27, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37844524

RESUMEN

OBJECTIVE: Parietal resting-state electroencephalographic (rsEEG) alpha (8-10 Hz) source connectivity is abnormal in HIV-positive persons. Here we tested whether this abnormality may be associated with subcortical white matter vascular lesions in the cerebral hemispheres. METHODS: Clinical, rsEEG, and magnetic resonance imaging (MRI) datasets in 38 HIV-positive persons and clinical and rsEEG datasets in 13 healthy controls were analyzed. Radiologists visually evaluated the subcortical white matter hyperintensities from T2-weighted FLAIR MRIs (i.e., Fazekas scale). In parallel, neurophysiologists estimated the eLORETA rsEEG source lagged linear connectivity from parietal cortical regions of interest. RESULTS: Compared to the HIV participants with no/negligible subcortical white matter hyperintensities, the HIV participants with mild/moderate subcortical white matter hyperintensities showed lower parietal interhemispheric rsEEG alpha lagged linear connectivity. This effect was also observed in HIV-positive persons with unimpaired cognition. This rsEEG marker allowed good discrimination (area under the receiver operating characteristic curve > 0.80) between the HIV-positive individuals with different amounts of subcortical white matter hyperintensities. CONCLUSIONS: The parietal rsEEG alpha source connectivity is associated with subcortical white matter vascular lesions in HIV-positive persons, even without neurocognitive disorders. SIGNIFICANCE: Those MRI-rsEEG markers may be used to screen HIV-positive persons at risk of neurocognitive disorders.


Asunto(s)
Enfermedad de Alzheimer , Infecciones por VIH , Sustancia Blanca , Humanos , Corteza Cerebral/fisiología , Sustancia Blanca/diagnóstico por imagen , Enfermedad de Alzheimer/psicología , Electroencefalografía/métodos , Imagen por Resonancia Magnética , Infecciones por VIH/diagnóstico por imagen
3.
Mov Disord ; 38(12): 2173-2184, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37700489

RESUMEN

BACKGROUND: Excessive glutamatergic transmission in the striatum is implicated in Parkinson's disease (PD) progression. Astrocytes maintain glutamate homeostasis, protecting from excitotoxicity through the glutamate-aspartate transporter (GLAST), whose alterations have been reported in PD. Noninvasive brain stimulation using intermittent theta-burst stimulation (iTBS) acts on striatal neurons and glia, inducing neuromodulatory effects and functional recovery in experimental parkinsonism. OBJECTIVE: Because PD is associated with altered astrocyte function, we hypothesized that acute iTBS, known to rescue striatal glutamatergic transmission, exerts regional- and cell-specific effects through modulation of glial functions. METHODS: 6-Hydroxydopamine-lesioned rats were exposed to acute iTBS, and the areas predicted to be more responsive by a biophysical, hyper-realistic computational model that faithfully reconstructs the experimental setting were analyzed. The effects of iTBS on glial cells and motor behavior were evaluated by molecular and morphological analyses, and CatWalk and Stepping test, respectively. RESULTS: As predicted by the model, the hippocampus, cerebellum, and striatum displayed a marked c-FOS activation after iTBS, with the striatum showing specific morphological and molecular changes in the astrocytes, decreased phospho-CREB levels, and recovery of GLAST. Striatal-dependent motor performances were also significantly improved. CONCLUSION: These data uncover an unknown iTBS effect on astrocytes, advancing the understanding of the complex mechanisms involved in TMS-mediated functional recovery. Data on numerical dosimetry, obtained with a degree of anatomical details never before considered and validated by the biological findings, provide a framework to predict the electric-field induced in different specific brain areas and associate it with functional and molecular changes. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Trastornos Parkinsonianos , Ratas , Animales , Astrocitos , Estimulación Magnética Transcraneal , Trastornos Parkinsonianos/terapia , Cuerpo Estriado , Fenómenos Magnéticos
4.
Cereb Cortex ; 33(20): 10514-10527, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37615301

RESUMEN

Here we tested the hypothesis of a relationship between the cortical default mode network (DMN) structural integrity and the resting-state electroencephalographic (rsEEG) rhythms in patients with Alzheimer's disease with dementia (ADD). Clinical and instrumental datasets in 45 ADD patients and 40 normal elderly (Nold) persons originated from the PDWAVES Consortium (www.pdwaves.eu). Individual rsEEG delta, theta, alpha, and fixed beta and gamma bands were considered. Freeware platforms served to derive (1) the (gray matter) volume of the DMN, dorsal attention (DAN), and sensorimotor (SMN) cortical networks and (2) the rsEEG cortical eLORETA source activities. We found a significant positive association between the DMN gray matter volume, the rsEEG alpha source activity estimated in the posterior DMN nodes (parietal and posterior cingulate cortex), and the global cognitive status in the Nold and ADD participants. Compared with the Nold, the ADD group showed lower DMN gray matter, lower rsEEG alpha source activity in those nodes, and lower global cognitive status. This effect was not observed in the DAN and SMN. These results suggest that the DMN structural integrity and the rsEEG alpha source activities in the DMN posterior hubs may be related and predict the global cognitive status in ADD and Nold persons.

7.
Clin Neurophysiol ; 132(1): 232-245, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33433332

RESUMEN

OBJECTIVE: This retrospective and exploratory study tested the accuracy of artificial neural networks (ANNs) at detecting Alzheimer's disease patients with dementia (ADD) based on input variables extracted from resting-state electroencephalogram (rsEEG), structural magnetic resonance imaging (sMRI) or both. METHODS: For the classification exercise, the ANNs had two architectures that included stacked (autoencoding) hidden layers recreating input data in the output. The classification was based on LORETA source estimates from rsEEG activity recorded with 10-20 montage system (19 electrodes) and standard sMRI variables in 89 ADD and 45 healthy control participants taken from a national database. RESULTS: The ANN with stacked autoencoders and a deep leaning model representing both ADD and control participants showed classification accuracies in discriminating them of 80%, 85%, and 89% using rsEEG, sMRI, and rsEEG + sMRI features, respectively. The two ANNs with stacked autoencoders and a deep leaning model specialized for either ADD or control participants showed classification accuracies of 77%, 83%, and 86% using the same input features. CONCLUSIONS: The two architectures of ANNs using stacked (autoencoding) hidden layers consistently reached moderate to high accuracy in the discrimination between ADD and healthy control participants as a function of the rsEEG and sMRI features employed. SIGNIFICANCE: The present results encourage future multi-centric, prospective and longitudinal cross-validation studies using high resolution EEG techniques and harmonized clinical procedures towards clinical applications of the present ANNs.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Encéfalo/fisiopatología , Redes Neurales de la Computación , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/fisiopatología , Encéfalo/diagnóstico por imagen , Electroencefalografía , Humanos , Imagen por Resonancia Magnética , Estudios Retrospectivos
8.
Front Psychol ; 11: 543773, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33132952

RESUMEN

Silence is an important aspect of various meditation practices, but little work has focused specifically on the underlying neurophysiology of silence-related meditative practice, and on how it relates to the self-reported experiences of practitioners. To expand current knowledge regarding the neurophenomenology of silence in meditation, we directly investigated first-person reports of silence-related experiences during the practice of Quadrato Motor Training (QMT) and their association with changes in fractional anisotropy (FA). Participants recorded their cognitive, emotional, and physical experiences upon beginning QMT and again after 6 weeks of QMT practice. These reports were evaluated qualitatively and quantitatively. Findings showed that change between the two time points in self-reported silence-related experiences was negatively correlated with change in attentional effort, and positively correlated with changes in the left uncinate fasciculus. These results expand current knowledge regarding the neuroanatomical correlates of silence-related experiences during meditation.

9.
Neuroradiology ; 62(7): 833-841, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32246178

RESUMEN

PURPOSE: Patients with Crohn's disease (CD) undergo multiple gadolinium-based contrast agent injections across their lifespan to enhance signal intensity of the intestinal wall and differentiate active from quiescent inflammatory disease. Thus, CD patients are prone to gadolinium accumulation in the brain and represent a non-neurological population to explore gadolinium-related brain toxicity. Possible effects are expected to be greater on the cerebellar network due to the high propensity of the dentate nucleus to accumulate gadolinium. Herein, we provide a whole-brain network analysis of resting-state fMRI dynamics in long-term quiescent CD patients with normal renal function and MRI evidence of gadolinium deposition in the brain. METHODS: Fifteen patients with CD and 16 healthy age- and gender-matched controls were enrolled in this study. Relevant resting-state networks (RSNs) were identified using independent component analysis (ICA) from functional magnetic resonance imaging data. An unpaired two-sample t test (with age and sex as nuisance variables) was used to investigate between different RSNs. Clusters were determined by using threshold-free cluster enhancement and a family-wise error corrected cluster significance threshold of p < 0.05. RESULTS: Patients showed significantly decreased resting-state functional connectivity (p < 0.05, FWE corrected) of several regions of the right frontoparietal (FPR) and the dorsal attention (DAN) RSNs. No differences between the two groups were found in the functional connectivity maps of all the other RSNs, including the cerebellar network. CONCLUSION: Our findings suggest a non-significant impact of gadolinium deposition on within-network cerebellar functional connectivity of long-term quiescent CD patients.


Asunto(s)
Mapeo Encefálico/métodos , Cerebelo/metabolismo , Medios de Contraste/farmacocinética , Enfermedad de Crohn/diagnóstico por imagen , Gadolinio DTPA/farmacocinética , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
J Psychiatry Neurosci ; 44(5): 324-339, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30994310

RESUMEN

Background: Anorexia nervosa and bulimia nervosa are complex mental disorders, and their etiology is still not fully understood. This paper reviews the literature on diffusion tensor imaging studies in patients with anorexia nervosa and bulimia nervosa to explore the usefulness of white matter microstructural analysis in understanding the pathophysiology of eating disorders. Methods: We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify diffusion tensor imaging studies that compared patients with an eating disorder to control groups. We searched relevant databases for studies published from database inception to August 2018, using combinations of select keywords. We categorized white matter tracts according to their 3 main classes: projection (i.e., thalamo­cortical), association (i.e., occipital­parietal­temporal­frontal) and commissural (e.g., corpus callosum). Results: We included 19 papers that investigated a total of 427 participants with current or previous eating disorders and 444 controls. Overall, the studies used different diffusion tensor imaging approaches and showed widespread white matter abnormalities in patients with eating disorders. Despite differences among the studies, patients with anorexia nervosa showed mainly white matter microstructural abnormalities of thalamo­cortical tracts (i.e., corona radiata, thalamic radiations) and occipital­parietal­temporal­frontal tracts (i.e., left superior longitudinal and inferior fronto-occipital fasciculi). It was less clear whether white matter alterations persist after recovery from anorexia nervosa. Available data on bulimia nervosa were partially similar to those for anorexia nervosa. Limitations: Study sample composition and diffusion tensor imaging analysis techniques were heterogeneous. The number of studies on bulimia nervosa was too limited to be conclusive. Conclusion: White matter microstructure appears to be affected in anorexia nervosa, and these alterations may play a role in the pathophysiology of this eating disorder. Although we found white matter alterations in bulimia nervosa that were similar to those in anorexia nervosa, white matter changes in bulimia nervosa remain poorly investigated, and these findings were less conclusive. Further studies with longitudinal designs and multi-approach analyses are needed to better understand the role of white matter changes in eating disorders.


Asunto(s)
Anorexia Nerviosa/diagnóstico por imagen , Bulimia Nerviosa/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Anorexia Nerviosa/fisiopatología , Bulimia Nerviosa/fisiopatología , Corteza Cerebral/fisiopatología , Imagen de Difusión Tensora , Humanos , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Occipital/fisiopatología , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Parietal/fisiopatología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiopatología , Tálamo/fisiopatología , Sustancia Blanca/fisiopatología
11.
J Magn Reson Imaging ; 50(2): 445-455, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30681245

RESUMEN

BACKGROUND: The dentate nuclei of the cerebellum are the areas where gadolinium predominantly accumulates. It is not yet known whether gadolinium deposition affects brain functions. PURPOSE/HYPOTHESIS: To assess whether gadolinium-dependent high signal intensity of the cerebellum on T1 -weighted images of nonneurological adult patients with Crohn's disease is associated with modifications of resting-state functional connectivity (RSFC) of the cerebellum and dentate nucleus. STUDY TYPE: Observational, cross-sectional. POPULATION: Fifteen patients affected by Crohn's disease were compared with 16 healthy age- and gender-matched control subjects. All participants underwent neurological, neurocognitive-psychological assessment, and blood sampling. FIELD STRENGTH/SEQUENCE: 1.5-T magnet blood oxygenation level-dependent (BOLD) functional MRI. ASSESSMENT: High signal intensity on T1 -weighted images, cerebellum functional connectivity, neurocognitive performance, and blood circulating gadolinium levels. STATISTICAL TESTS: An unpaired two-sample t-test (age and sex were nuisance variables) was used to investigate between-group differences in cerebellar and dentate nucleus functional connectivity. Z-statistical images were set using clusters determined by Z > 2.3 and a familywise error (FWE)-corrected cluster significance threshold of P = 0.05. RESULTS: Dentate nuclei RSFC was not different (P = n.s.) between patients with gadolinium-dependent high signal intensity on T1 -weighted images and controls. Pre- and postcentral gyrus bilaterally and the right supplementary motor cortex showed a decrease of RSFC with the cerebellum hemispheres (P < 0.05 FWE-corrected) and was related to disease duration but not to gadodiamide cumulative doses (P = n.s.). DATA CONCLUSION: Crohn's disease patients with gadolinium-dependent hyperintense dentate nuclei on unenhanced T1 -weighted images do not show dentate nucleus RSFC changes. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2019;50:445-455.


Asunto(s)
Núcleos Cerebelosos/fisiología , Medios de Contraste/metabolismo , Enfermedad de Crohn , Gadolinio/sangre , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Núcleos Cerebelosos/diagnóstico por imagen , Núcleos Cerebelosos/metabolismo , Cerebelo/diagnóstico por imagen , Cerebelo/metabolismo , Cerebelo/fisiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Eur J Ophthalmol ; 29(2): 148-157, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29972313

RESUMEN

PURPOSE: To investigate the 2- and 5-year publication rates of abstracts presented at major international ophthalmology meetings. METHODS: We analyzed a random selection of 20% of free papers and posters presented at the 2010 meeting of the Association for Research in Vision and Ophthalmology, the American Academy of Ophthalmology, the European Association for Vision and Eye Research, the Asia-Pacific Academy of Ophthalmology, and the 2009 European Society of Ophthalmology meeting. The PubMed (MEDLINE) database was searched to identify matching journal articles. Data collection included: topic, geographic origin, presentation type, publication status, and impact factor. A multivariate logistic regression model was used to assess odds of publication and impact factor. RESULTS: Our analysis included 1742 research abstracts. The overall 2- and 5-year publication rates were 33.3% (n = 579) and 47.2% (n = 823), respectively. The highest publication rates were found for Association for Research in Vision and Ophthalmology (36.1% and 51.9%, p < 0.0001), paper presentations (44.5% and 60.5%, p < 0.0001), researches from Oceania (35.8% and 57.1%, p < 0.05) and North America (36.2% and 50.5%, p < 0.05), and Basic science studies (44% and 60.3%, p < 0.01). After adjustments, higher odds of publication were shown by the Association for Research in Vision and Ophthalmology and the American Academy of Ophthalmology meetings (p < 0.0001), papers (p < 0.0001), and Basic science (p < 0.05). The median impact factor was 3.20 (interquartile range = 1.90-3.40). CONCLUSION: Less than half of abstracts presented at the major ophthalmology meetings reach publication within 5 years of their initial presentation. Professionals attending meetings may consider adopting a more critical approach to the preliminary results reported in presented abstracts. Increasing publication rates and reducing potential publication bias is of interest.

13.
Front Hum Neurosci ; 11: 590, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29270117

RESUMEN

Diffusion tensor imaging (DTI) is an important way to characterize white matter (WM) microstructural changes. While several cross-sectional DTI studies investigated possible links between mindfulness practices and WM, only few longitudinal investigations focused on the effects of these practices on WM architecture, behavioral change, and the relationship between them. To this aim, in the current study, we chose to conduct an unbiased tract-based spatial statistics (TBSS) analysis (n = 35 healthy participants) to identify longitudinal changes in WM diffusion parameters following 6 and 12 weeks of daily Quadrato Motor Training (QMT), a whole-body mindful movement practice aimed at improving well-being by enhancing attention, coordination, and creativity. We also investigated the possible relationship between training-induced WM changes and concomitant changes in creativity, self-efficacy, and motivation. Our results indicate that following 6 weeks of daily QMT, there was a bilateral increase of fractional anisotropy (FA) in tracts related to sensorimotor and cognitive functions, including the corticospinal tracts, anterior thalamic radiations, and uncinate fasciculi, as well as in the left inferior fronto-occipital, superior and inferior longitudinal fasciculi. Interestingly, significant FA increments were still present after 12 weeks of QMT in most of the above WM tracts, but only in the left hemisphere. FA increase was accompanied by a significant decrease of radial diffusivity (RD), supporting the leading role of myelination processes in training-related FA changes. Finally, significant correlations were found between training-induced diffusion changes and increased self-efficacy as well as creativity. Together, these findings suggest that QMT can improve WM integrity and support the existence of possible relationships between training-related WM microstructural changes and behavioral change.

14.
Psychiatry Res Neuroimaging ; 266: 138-145, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28666248

RESUMEN

Few studies have examined white matter (WM) integrity in long-lasting Anorexia Nervosa (AN) patients using Diffusion Tensor Imaging (DTI). In this paper, we investigated WM integrity at the earliest stages of AN (i.e. less than 6 months duration). Fourteen treatment-naive female adolescents with AN restrictive type (AN-r) in its earliest stages and 15 age-matched healthy females received brain MRI. Fractional Anisotropy (FA), Axial Diffusivity (AD), Radial diffusivity (RD), and Mean Diffusivity (MD) maps were computed from DTI data using Tract-Based Spatial Statistics analysis. AN-r patients showed FA decreases compared to controls (pFWE < 0.05) mainly in left anterior and superior corona radiata and left superior longitudinal fasciculus. AN-r patients also showed decreased AD in superior longitudinal fasciculus bilaterally and left superior and anterior corona radiata, (pFWE < 0.05). No significant differences were found in RD and MD values between the two groups. FA and AD integrity appears to be specifically affected at the earliest stages of AN. Alterations in the microstructural properties of the above mentioned tracts, also involved in cognitive control and visual perception and processing, may be early mechanisms of vulnerability/resilience of WM in AN and sustain the key symptoms of AN, such as impaired cognitive flexibility and body image distortion.


Asunto(s)
Anorexia Nerviosa/patología , Imagen de Difusión Tensora/métodos , Sustancia Blanca/patología , Adolescente , Anorexia Nerviosa/diagnóstico por imagen , Femenino , Humanos , Sustancia Blanca/diagnóstico por imagen
15.
Front Hum Neurosci ; 11: 282, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28659773

RESUMEN

Quadrato Motor Training (QMT) is a new training paradigm, which was found to increase cognitive flexibility, creativity and spatial cognition. In addition, QMT was reported to enhance inter- and intra-hemispheric alpha coherence as well as Fractional Anisotropy (FA) in a number of white matter pathways including corpus callosum. Taken together, these results seem to suggest that electrophysiological and structural changes induced by QMT may be due to an enhanced interplay and communication of the different brain areas within and between the right and the left hemisphere. In order to test this hypothesis using the exact low-resolution brain electromagnetic tomography (eLORETA), we estimated the current neural density and lagged linear connectivity (LLC) of the alpha band in the resting state electroencephalography (rsEEG) recorded with open (OE) and closed eyes (CE) at three different time points, following 6 and 12 weeks of daily QMT. Significant changes were observed for the functional connectivity. In particular, we found that limbic and fronto-temporal alpha connectivity in the OE condition increased after 6 weeks, while it enhanced at the CE condition in occipital network following 12-weeks of daily training. These findings seem to show that the QMT may have dissociable long-term effects on the functional connectivity depending on the different ways of recording rsEEG. OE recording pointed out a faster onset of Linear Lag Connectivity modulations that tend to decay as quickly, while CE recording showed sensible effect only after the complete 3-months training.

16.
Psychiatry Res Neuroimaging ; 247: 42-8, 2016 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-26651180

RESUMEN

There is increasing evidence of white matter (WM) pathology in schizophrenia, but its role at the very early stage of the disorder remains unclear. In an exploration of WM microstructure in ultra-high risk (UHR) subjects and first episode schizophrenia (FES), 34 FES, 27 UHR and 26 healthy control (HC) subjects underwent a magnetic resonance imaging (MRI) tract based spatial statistics (TBSS) investigation. Whole brain fractional anisotropy (FA), mean diffusivity (MD), radial (RD) and axial diffusivity (AD) values were extracted. UHR subjects who later developed psychosis showed lower FA compared with HC in the corpus callosum (CC), the left superior and inferior longitudinal fasciculus, the left inferior fronto-occipital fasciculs (IFO), and the forceps; RD was significantly higher in the CC, the forceps, the anterior thalamic radiation bilaterally, and the cingulum bundle. FES, compared to HC, showed a significant FA reduction of the CC, the superior and inferior longitudinal fasciculi bilaterally, the IFO bilaterally, the corona radiate bilaterally, and the forceps; while RD was found to be significantly increased in the left superior longitudinal fasciculus. UHR who later developed psychosis had WM abnormalities affecting brain pathways that are crucial for intra- and inter-hemispheric connections.


Asunto(s)
Mapeo Encefálico , Encéfalo/patología , Esquizofrenia/complicaciones , Sustancia Blanca/patología , Adolescente , Adulto , Anisotropía , Estudios de Casos y Controles , Cuerpo Calloso/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Riesgo , Esquizofrenia/patología , Adulto Joven
17.
J Alzheimers Dis ; 49(1): 159-77, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26444753

RESUMEN

Here we presented a single electroencephalographic (EEG) marker for a neurophysiological assessment of Alzheimer's disease (AD) patients already diagnosed by current guidelines. The ability of the EEG marker to classify 127 AD individuals and 121 matched cognitively intact normal elderly (Nold) individuals was tested. Furthermore, its relationship to AD patients' cognitive status and structural brain integrity was examined. Low-resolution brain electromagnetic tomography (LORETA) freeware estimated cortical sources of resting state eyes-closed EEG rhythms. The EEG marker was defined as the ratio between the activity of parieto-occipital cortical sources of delta (2-4 Hz) and low-frequency alpha (8-10.5 Hz) rhythms. Results showed 77.2% of sensitivity in the recognition of the AD individuals; 65% of specificity in the recognition of the Nold individuals; and 0.75 of area under the receiver-operating characteristic curve. Compared to the AD subgroup with the EEG maker within one standard deviation of the Nold mean (EEG-), the AD subgroup with EEG+ showed lower global cognitive status, as revealed by Mini-Mental State Evaluation score, and more abnormal values of white-matter and cerebrospinal fluid normalized volumes, as revealed by structural magnetic resonance imaging. We posit that cognitive and functional status being equal, AD patients with EEG+ should receive special clinical attention due to a neurophysiological "frailty". EEG+ label can be also used in clinical trials (i) to form homogeneous groups of AD patients diagnosed by current guidelines and (ii) as end-point to evaluate intervention effects.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Trastornos del Conocimiento/fisiopatología , Electroencefalografía , Lóbulo Occipital/fisiopatología , Anciano , Biomarcadores , Mapeo Encefálico , Estudios de Casos y Controles , Femenino , Humanos , Italia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Curva ROC , Descanso , Turquía
18.
Int J Psychophysiol ; 103: 110-7, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-25660300

RESUMEN

Amnesic mild cognitive impairment (MCI) represents a risk of developing Alzheimer's disease (AD), but not all MCI subjects progress to dementia of AD type. Magnetic resonance imaging (MRI) of cortical and hippocampal atrophy supports early diagnosis of AD in MCI subjects, while frontal event-related oscillations (EROs) at delta frequencies (<4Hz) are appealing markers for this purpose, as they are both cost-effective and largely available. The present study tested the hypothesis that these EROs reflect cortical frontal neurodegeneration in the continuum between normal and amnesic MCI subjects. EROs and volumetric MRI data were recorded in 28 amnesic MCI and in 28 healthy elderly controls (HCs). EROs were collected during a standard visual oddball paradigm including frequent (66.6%) and rare (33.3%; targets to be mentally counted) stimuli. Peak-to-peak amplitude of delta target EROs (<4Hz) was measured. Volume of frontal cortex was estimated from MRIs. Frontal volume was lower in MCI compared to the HC group. Furthermore, widespread delta target EROs were lower in amplitude in the former than in the latter group. Finally, there was a positive correlation between frontal volume and frontal delta target EROs in MCI and HC subjects as a whole group. These results suggest that frontal delta EROs reflect frontal neurodegeneration in the continuum between normal and amnesic MCI subjects.


Asunto(s)
Mapeo Encefálico , Disfunción Cognitiva/patología , Ritmo Delta/fisiología , Lóbulo Frontal/fisiopatología , Anciano , Análisis de Varianza , Estudios de Casos y Controles , Disfunción Cognitiva/diagnóstico por imagen , Electroencefalografía , Femenino , Lóbulo Frontal/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
19.
PLoS One ; 10(10): e0137977, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26469868

RESUMEN

OBJECTIVE: The present study shows the results of a double-blind sham-controlled pilot trial to test whether measurable stimulus-specific functional connectivity changes exist after Automatic Mechanical Peripheral Stimulation (AMPS) in patients with idiopathic Parkinson Disease. METHODS: Eleven patients (6 women and 5 men) with idiopathic Parkinson Disease underwent brain fMRI immediately before and after sham or effective AMPS. Resting state Functional Connectivity (RSFC) was assessed using the seed-ROI based analysis. Seed ROIs were positioned on basal ganglia, on primary sensory-motor cortices, on the supplementary motor areas and on the cerebellum. Individual differences for pre- and post-effective AMPS and pre- and post-sham condition were obtained and first entered in respective one-sample t-test analyses, to evaluate the mean effect of condition. RESULTS: Effective AMPS, but not sham stimulation, induced increase of RSFC of the sensory motor cortex, nucleus striatum and cerebellum. Secondly, individual differences for both conditions were entered into paired group t-test analysis to rule out sub-threshold effects of sham stimulation, which showed stronger connectivity of the striatum nucleus with the right lateral occipital cortex and the cuneal cortex (max Z score 3.12) and with the right anterior temporal lobe (max Z score 3.42) and of the cerebellum with the right lateral occipital cortex and the right cerebellar cortex (max Z score 3.79). CONCLUSIONS: Our results suggest that effective AMPS acutely increases RSFC of brain regions involved in visuo-spatial and sensory-motor integration. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that automatic mechanical peripheral stimulation is effective in modulating brain functional connectivity of patients with Parkinson Disease at rest. TRIAL REGISTRATION: Clinical Trials.gov NCT01815281.


Asunto(s)
Encéfalo/fisiopatología , Fenómenos Mecánicos , Red Nerviosa/fisiopatología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Sistema Nervioso Periférico/fisiopatología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Descanso , Resultado del Tratamiento
20.
Front Psychol ; 6: 1021, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26257679

RESUMEN

Quadrato Motor Training (QMT) is a whole-body movement contemplative practice aimed at increasing health and well-being. Previous research studying the effect of one QMT session suggested that one of its means for promoting health is by enhancing cognitive flexibility, an important dimension of creativity. Yet, little is known about the effect of a longer QMT practice on creativity, or the relative contribution of the cognitive and motor aspects of the training. Here, we continue this line of research in two inter-related studies, examining the effects of prolonged QMT. In the first, we investigated the effect of 4-weeks of daily QMT on creativity using the Alternate Uses (AUs) Task. In order to determine whether changes in creativity were driven by the cognitive or the motor aspects of the training, we used two control groups: Verbal Training (VT, identical cognitive training with verbal response) and Simple Motor Training (SMT, similar motor training with reduced choice requirements). Twenty-seven participants were randomly assigned to one of the groups. Following training, cognitive flexibility significantly increased in the QMT group, which was not the case for either the SMT or VT groups. In contrast to one QMT session, ideational fluency was also significantly increased. In the second study, we conducted a pilot longitudinal structural magnetic resonance imaging and diffusion tensor imaging (4-weeks QMT). We report gray matter volume and fractional anisotropy changes, in several regions, including the cerebellum, previously related to interoceptive accuracy. The anatomical changes were positively correlated with cognitive flexibility scores. Albeit the small sample size and preliminary nature of the findings, these results provide support for the hypothesized creativity-motor connection. The results are compared to other contemplative studies, and discussed in light of theoretical models integrating cognitive flexibility, embodiment and the motor system.

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