RESUMEN
Alcohol consumption during adolescence has been associated with neuroanatomical abnormalities and the appearance of future disorders. However, the latest advances in this field point to the existence of risk profiles which may lead to some individuals into an early consumption. To date, some studies have established predictive models of consumption based on sociodemographic, behavioral, and anatomical-functional variables using MRI. However, the neuroimaging variables employed are usually restricted to local and hemodynamic phenomena. Given the potential of connectome approaches, and the high temporal dynamics of electrophysiology, we decided to explore the relationship between future alcohol consumption and electrophysiological connectivity measured by MEG in a cohort of 83 individuals aged 14 to 16. As a result, we found a positive correlation between alcohol consumption and the functional connectivity in frontal, parietal, and frontoparietal connections. Once this relationship was described, multivariate linear regression analyses were used to evaluate the predictive capacity of functional connectivity in conjunction with other neuroanatomical and behavioral variables described in the literature. Finally, the multivariate linear regression analysis determined the importance of anatomical and functional variables in the prediction of alcohol consumption but failed to find associations with impulsivity, sensation seeking, and executive function scales. In conclusion, the predictive traits obtained in these models were closely associated with changes occurring during adolescence, suggesting the existence of different paths in neurodevelopment that have the potential to influence adolescents' relationship with alcohol consumption.
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Consumo de Alcohol en Menores , Humanos , Adolescente , Masculino , Femenino , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Consumo de Bebidas Alcohólicas , Imagen por Resonancia Magnética , ConectomaRESUMEN
Changes in brain oscillatory activity are commonly used as biomarkers both in cognitive neuroscience and in neuropsychiatric conditions. However, little is known about how its profile changes across maturation. Here we use regression models to characterize magnetoencephalography power changes within classical frequency bands in a sample of 792 healthy participants, covering the range 13 to 80 years old. Our findings unveil complex, non-linear power trajectories that defy the traditional linear paradigm, with notable cortical region variations. Interestingly, slow wave activity increases correlate with improved cognitive performance throughout life and larger gray matter volume in the elderly. Conversely, fast wave activity diminishes in adulthood. Elevated low-frequency activity during aging, traditionally seen as compensatory, may also signify neural deterioration. This dual interpretation, highlighted by our study, reveals the intricate dynamics between brain oscillations, cognitive performance, and aging. It advances our understanding of neurodevelopment and aging by emphasizing the regional specificity and complexity of brain rhythm changes, with implications for cognitive and structural integrity.
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Envejecimiento , Encéfalo , Magnetoencefalografía , Humanos , Anciano , Envejecimiento/fisiología , Adulto , Magnetoencefalografía/métodos , Persona de Mediana Edad , Femenino , Masculino , Adulto Joven , Encéfalo/fisiología , Encéfalo/crecimiento & desarrollo , Anciano de 80 o más Años , Adolescente , Ondas Encefálicas/fisiología , Cognición/fisiología , Sustancia Gris/fisiología , Sustancia Gris/diagnóstico por imagenRESUMEN
BACKGROUND: Neurophysiological studies recognized that Autism Spectrum Disorder (ASD) is associated with altered patterns of over- and under-connectivity. However, little is known about network organization in children with ASD in the early phases of development and its correlation with the severity of core autistic features. METHODS: The present study aimed at investigating the association between brain connectivity derived from MEG signals and severity of ASD traits measured with different diagnostic clinical scales, in a sample of 16 children with ASD aged 2 to 6 years. RESULTS: A significant correlation emerged between connectivity strength in cortical brain areas implicated in several resting state networks (Default mode, Central executive, Salience, Visual and Sensorimotor) and the severity of communication anomalies, social interaction problems, social affect problems, and repetitive behaviors. Seed analysis revealed that this pattern of correlation was mainly caused by global rather than local effects. CONCLUSIONS: The present evidence suggests that altered connectivity strength in several resting state networks is related to clinical features and may contribute to neurofunctional correlates of ASD. Future studies implementing the same method on a wider and stratified sample may further support functional connectivity as a possible biomarker of the condition.
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Trastorno del Espectro Autista , Encéfalo , Magnetoencefalografía , Humanos , Trastorno del Espectro Autista/fisiopatología , Trastorno del Espectro Autista/diagnóstico por imagen , Masculino , Preescolar , Femenino , Niño , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Descanso/fisiología , Vías Nerviosas/fisiopatología , Vías Nerviosas/diagnóstico por imagen , ConectomaRESUMEN
Animal studies have established that acute alcohol increases neural inhibition and that frequent intoxication episodes elicit neuroadaptive changes in the excitatory/inhibitory neurotransmission balance. To compensate for the depressant effects of alcohol, neural hyperexcitability develops in alcohol use disorder and is manifested through withdrawal symptoms. It is unclear, however, whether neuroadaptive changes can be observed in young, emerging adults at lower levels of consumption in the absence of withdrawal symptoms. Here, we used an anatomically constrained magnetoencephalography method to assess cortical excitability in two independent sets of experiments. We measured early visual activity (1) in social drinkers during alcohol intoxication versus placebo conditions and (2) in parallel cohorts of sober binge drinkers (BDs) and light drinkers (LDs). Acute alcohol intoxication attenuated early sensory activity in the visual cortex in social drinkers, confirming its inhibitory effects on neurotransmission. In contrast, sober BDs showed greater neural responsivity compared with a matched group of LDs. A positive correlation between alcohol consumption and neural activity in BDs is indicative of cortical hyperexcitability associated with hazardous drinking. Furthermore, neural responsivity was positively correlated with alcohol intake in social drinkers whose drinking did not reach binge levels. This study provides novel evidence of compensatory imbalance reflected in the downregulation of inhibitory and upregulation of excitatory signaling associated with binge drinking in young, emerging adults. By contrasting acute effects and a history of BD, these results support the mechanistic model of allostasis. Direct neural measures are sensitive to synaptic currents and could serve as biomarkers of neuroadaptation.
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Intoxicación Alcohólica/psicología , Alostasis/efectos de los fármacos , Atención/efectos de los fármacos , Consumo Excesivo de Bebidas Alcohólicas/psicología , Magnetoencefalografía , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/psicología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
BACKGROUND: Cognitive stimulation therapy appears to show promising results in the rehabilitation of impaired cognitive processes in attention deficit hyperactivity disorder. OBJECTIVE: Encouraged by this evidence and the ever-increasing use of technology and artificial intelligence for therapeutic purposes, we examined whether cognitive stimulation therapy implemented on a mobile device and controlled by an artificial intelligence engine can be effective in the neurocognitive rehabilitation of these patients. METHODS: In this randomized study, 29 child participants (25 males) underwent training with a smart, digital, cognitive stimulation program (KAD_SCL_01) or with 3 commercial video games for 12 weeks, 3 days a week, 15 minutes a day. Participants completed a neuropsychological assessment and a preintervention and postintervention magnetoencephalography study in a resting state with their eyes closed. In addition, information on clinical symptoms was collected from the child´s legal guardians. RESULTS: In line with our main hypothesis, we found evidence that smart, digital, cognitive treatment results in improvements in inhibitory control performance. Improvements were also found in visuospatial working memory performance and in the cognitive flexibility, working memory, and behavior and general executive functioning behavioral clinical indexes in this group of participants. Finally, the improvements found in inhibitory control were related to increases in alpha-band power in all participants in the posterior regions, including 2 default mode network regions of the interest: the bilateral precuneus and the bilateral posterior cingulate cortex. However, only the participants who underwent cognitive stimulation intervention (KAD_SCL_01) showed a significant increase in this relationship. CONCLUSIONS: The results seem to indicate that smart, digital treatment can be effective in the inhibitory control and visuospatial working memory rehabilitation in patients with attention deficit hyperactivity disorder. Furthermore, the relation of the inhibitory control with alpha-band power changes could mean that these changes are a product of plasticity mechanisms or changes in the neuromodulatory dynamics. TRIAL REGISTRATION: ISRCTN Registry ISRCTN71041318; https://www.isrctn.com/ISRCTN71041318.
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Trastorno por Déficit de Atención con Hiperactividad , Inteligencia Artificial , Trastorno por Déficit de Atención con Hiperactividad/terapia , Encéfalo/diagnóstico por imagen , Niño , Cognición , Función Ejecutiva , Humanos , MasculinoRESUMEN
Hypersynchronization has been proposed as a synaptic dysfunction biomarker in the Alzheimer's disease continuum, reflecting the alteration of the excitation/inhibition balance. While animal models have verified this idea extensively, there is still no clear evidence in humans. Here we test this hypothesis, evaluating the risk of conversion from mild cognitive impairment (MCI) to Alzheimer's disease in a longitudinal study. We compared the functional resting state eyes-closed magnetoencephalographic networks of 54 patients with MCI who were followed-up every 6 months. According to their clinical outcome, they were split into: (i) the 'progressive' MCI (n = 27) group; and (ii) the 'stable' MCI group (n = 27). They did not differ in gender or educational level. For all participants, two magnetoencephalographic recordings were acquired. Functional connectivity was evaluated using the phase locking value. To extract the functional connectivity network with significant changes between both magnetoencephalographic recordings, we evaluated the functional connectivity ratio, defined as functional connectivity post-/pre-condition, in a network-based statistical model with an ANCOVA test with age as covariate. Two significant networks were found in the theta and beta bands, involving fronto-temporal and fronto-occipital connections, and showing a diminished functional connectivity ratio in the progressive MCI group. These topologies were then evaluated at each condition showing that at baseline, patients with progressive MCI showed higher synchronization than patients with stable MCI, while in the post-condition this pattern was reversed. These results may be influenced by two main factors in the post-condition: the increased synchrony in the stable MCI patients and the network failure in the progressive MCI patients. These findings may be explained as an 'X' form model where the hypersynchrony predicts conversion, leading subsequently to a network breakdown in progressive MCI. Patients with stable MCI showed an opposite phenomenon, which could indicate that they were a step beyond in the Alzheimer's disease continuum. This model would be able to predict the risk for the conversion to dementia in MCI patients.
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Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Neuroimagen , Pruebas NeuropsicológicasRESUMEN
Biomarkers useful for the predementia stages of Alzheimer's disease are needed. Electroencephalography and magnetoencephalography (MEG) are expected to provide potential biomarker candidates for evaluating the predementia stages of Alzheimer's disease. However, the physiological relevance of EEG/MEG signal changes and their role in pathophysiological processes such as amyloid-ß deposition and neurodegeneration need to be elucidated. We evaluated 28 individuals with mild cognitive impairment and 38 cognitively normal individuals, all of whom were further classified into amyloid-ß-positive mild cognitive impairment (n = 17, mean age 74.7 ± 5.4 years, nine males), amyloid-ß-negative mild cognitive impairment (n = 11, mean age 73.8 ± 8.8 years, eight males), amyloid-ß-positive cognitively normal (n = 13, mean age 71.8 ± 4.4 years, seven males), and amyloid-ß-negative cognitively normal (n = 25, mean age 72.5 ± 3.4 years, 11 males) individuals using Pittsburgh compound B-PET. We measured resting state MEG for 5 min with the eyes closed, and investigated regional spectral patterns of MEG signals using atlas-based region of interest analysis. Then, the relevance of the regional spectral patterns and their associations with pathophysiological backgrounds were analysed by integrating information from Pittsburgh compound B-PET, fluorodeoxyglucose-PET, structural MRI, and cognitive tests. The results demonstrated that regional spectral patterns of resting state activity could be separated into several types of MEG signatures as follows: (i) the effects of amyloid-ß deposition were expressed as the alpha band power augmentation in medial frontal areas; (ii) the delta band power increase in the same region was associated with disease progression within the Alzheimer's disease continuum and was correlated with entorhinal atrophy and an Alzheimer's disease-like regional decrease in glucose metabolism; and (iii) the global theta power augmentation, which was previously considered to be an Alzheimer's disease-related EEG/MEG signature, was associated with general cognitive decline and hippocampal atrophy, but was not specific to Alzheimer's disease because these changes could be observed in the absence of amyloid-ß deposition. The results suggest that these MEG signatures may be useful as unique biomarkers for the predementia stages of Alzheimer's disease.
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Enfermedad de Alzheimer/complicaciones , Mapeo Encefálico , Encéfalo/fisiopatología , Disfunción Cognitiva/etiología , Magnetoencefalografía/métodos , Síntomas Prodrómicos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides/metabolismo , Análisis de Varianza , Compuestos de Anilina/farmacocinética , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Escalas de Valoración Psiquiátrica , Tiazoles/farmacocinéticaRESUMEN
Synaptic dysfunction is a core deficit in Alzheimer's disease, preceding hallmark pathological abnormalities. Resting-state magnetoencephalography (MEG) was used to assess whether functional connectivity patterns, as an index of synaptic dysfunction, are associated with CSF biomarkers [i.e., phospho-tau (p-tau) and amyloid beta (Aß42) levels]. We studied 12 human subjects diagnosed with mild cognitive impairment due to Alzheimer's disease, comparing those with normal and abnormal CSF levels of the biomarkers. We also evaluated the association between aberrant functional connections and structural connectivity abnormalities, measured with diffusion tensor imaging, as well as the convergent impact of cognitive deficits and CSF variables on network disorganization. One-third of the patients converted to Alzheimer's disease during a follow-up period of 2.5 years. Patients with abnomal CSF p-tau and Aß42 levels exhibited both reduced and increased functional connectivity affecting limbic structures such as the anterior/posterior cingulate cortex, orbitofrontal cortex, and medial temporal areas in different frequency bands. A reduction in posterior cingulate functional connectivity mediated by p-tau was associated with impaired axonal integrity of the hippocampal cingulum. We noted that several connectivity abnormalities were predicted by CSF biomarkers and cognitive scores. These preliminary results indicate that CSF markers of amyloid deposition and neuronal injury in early Alzheimer's disease associate with a dual pattern of cortical network disruption, affecting key regions of the default mode network and the temporal cortex. MEG is useful to detect early synaptic dysfunction associated with Alzheimer's disease brain pathology in terms of functional network organization. SIGNIFICANCE STATEMENT: In this preliminary study, we used magnetoencephalography and an integrative approach to explore the impact of CSF biomarkers, neuropsychological scores, and white matter structural abnormalities on neural function in mild cognitive impairment. Disruption in functional connectivity between several pairs of cortical regions associated with abnormal levels of biomarkers, cognitive deficits, or with impaired axonal integrity of hippocampal tracts. Amyloid deposition and tau protein-related neuronal injury in early Alzheimer's disease are associated with synaptic dysfunction and a dual pattern of cortical network disorganization (i.e., desynchronization and hypersynchronization) that affects key regions of the default mode network and temporal areas.
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Péptidos beta-Amiloides/líquido cefalorraquídeo , Encéfalo/patología , Disfunción Cognitiva/líquido cefalorraquídeo , Disfunción Cognitiva/patología , Fragmentos de Péptidos/líquido cefalorraquídeo , Proteínas tau/líquido cefalorraquídeo , Anciano , Anciano de 80 o más Años , Mapeo Encefálico , Imagen de Difusión Tensora , Femenino , Humanos , Magnetocardiografía , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Pruebas NeuropsicológicasRESUMEN
Modulation of vocal pitch is a key speech feature that conveys important linguistic and affective information. Auditory feedback is used to monitor and maintain pitch. We examined induced neural high gamma power (HGP) (65-150 Hz) using magnetoencephalography during pitch feedback control. Participants phonated into a microphone while hearing their auditory feedback through headphones. During each phonation, a single real-time 400 ms pitch shift was applied to the auditory feedback. Participants compensated by rapidly changing their pitch to oppose the pitch shifts. This behavioral change required coordination of the neural speech motor control network, including integration of auditory and somatosensory feedback to initiate change in motor plans. We found increases in HGP across both hemispheres within 200 ms of pitch shifts, covering left sensory and right premotor, parietal, temporal, and frontal regions, involved in sensory detection and processing of the pitch shift. Later responses to pitch shifts (200-300 ms) were right dominant, in parietal, frontal, and temporal regions. Timing of activity in these regions indicates their role in coordinating motor change and detecting and processing of the sensory consequences of this change. Subtracting out cortical responses during passive listening to recordings of the phonations isolated HGP increases specific to speech production, highlighting right parietal and premotor cortex, and left posterior temporal cortex involvement in the motor response. Correlation of HGP with behavioral compensation demonstrated right frontal region involvement in modulating participant's compensatory response. This study highlights the bihemispheric sensorimotor cortical network involvement in auditory feedback-based control of vocal pitch.
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Retroalimentación Sensorial/fisiología , Lateralidad Funcional/fisiología , Red Nerviosa/fisiología , Percepción de la Altura Tonal/fisiología , Corteza Sensoriomotora/fisiología , Habla/fisiología , Estimulación Acústica/métodos , Potenciales Evocados Auditivos/fisiología , Femenino , Humanos , Magnetoencefalografía/métodos , Masculino , Estimulación Luminosa/métodosRESUMEN
BACKGROUND: In the last years different studies have reported an increase of amyotrophic lateral sclerosis (ALS) incidence, highlighting the role of the environment in this disease. This prompted us to review ALS cases diagnosed at our hospital in the last decade and to compare them with a previous ALS series reported in our region 30 years ago. METHODS: We reviewed those ALS cases diagnosed at our centre between 2004 and 2013. Subsequently, we compared them with the previous series regarding clinical and epidemiological features. RESULTS: A total of 53 patients (30 males, 23 females) were included. The annual incidence was 1.7 cases per 100,000 inhabitants (2.2 and 1.2 per 100,000 in males and females, respectively), which was significantly higher than in the previous series (1 case per 100,000 inhabitants). Otherwise, the clinical and epidemiological features were similar in both series. The median age at symptom onset was 67 years, with a median diagnosis delay of 6 months. About two thirds of the patients presented with systemic ALS, whereas the remaining had a bulbar onset. Weakness, dysphagia, and dysarthria were the most common clinical symptoms at diagnosis. The median survival from symptom onset was 22 months. CONCLUSION: After 3 decades, the annual incidence of ALS has almost doubled in our region. We did not find significant differences regarding other clinical or epidemiological features.
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Esclerosis Amiotrófica Lateral/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Esclerosis Amiotrófica Lateral/diagnóstico , Femenino , Humanos , Incidencia , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Salud Rural , España/epidemiología , Salud UrbanaRESUMEN
Two-dimensional difference gel electrophoresis (2-D DIGE)-based proteome analysis has revealed intrinsic insulin resistance in myotubes derived from type 2 diabetic patients. Using 2-D DIGE-based proteome analysis, we identified a subset of insulin-resistant proteins involved in protein turnover in skeletal muscle of type 2 diabetic patients, suggesting aberrant regulation of the protein homeostasis maintenance system underlying metabolic disease. We then validated the role of the ubiquitin-proteasome system (UPS) in myotubes to investigate whether impaired proteasome function may lead to metabolic arrest or insulin resistance. Myotubes derived from muscle biopsies obtained from people with normal glucose tolerance (NGT) or type 2 diabetes were exposed to the proteasome inhibitor bortezomib (BZ; Velcade) without or with insulin. BZ exposure increased protein carbonylation and lactate production yet impaired protein synthesis and UPS function in myotubes from type 2 diabetic patients, marking the existence of an insulin-resistant signature that was retained in cultured myotubes. In conclusion, BZ treatment further exacerbates insulin resistance and unmasks intrinsic features of metabolic disease in myotubes derived from type 2 diabetic patients. Our results highlight the existence of a confounding inherent abnormality in cellular protein dynamics in metabolic disease, which is uncovered through concurrent inhibition of the proteasome system.
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Diabetes Mellitus Tipo 2/metabolismo , Músculo Esquelético/metabolismo , Complejo de la Endopetidasa Proteasomal/fisiología , Ácidos Borónicos/farmacología , Bortezomib , Células Cultivadas , Diabetes Mellitus Tipo 2/enzimología , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Glucógeno/biosíntesis , Humanos , Insulina/farmacología , Resistencia a la Insulina , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/enzimología , Estrés Oxidativo/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Carbonilación Proteica/efectos de los fármacos , Proteoma/metabolismo , Pirazinas/farmacología , Interferencia de ARN , Transducción de SeñalRESUMEN
Objective: This study sought to identify magnetoencephalography (MEG) power spectra patterns associated with cerebrovascular damage (white matter hyperintensities - WMH) and their relationship with cognitive performance and brain structure integrity in aging individuals without cognitive impairment. Methods: We hypothesized a "slowness" pattern characterized by increased power in δ and θ bands and decreased power in the ß band associated with the severity of vascular damage. MEG signals were analyzed in cognitively healthy older adults to investigate these associations. Results: Contrary to expectations, we did not observe an increase in δ and θ power. However, we found a significant negative correlation between ß band power and WMH volume. This ß power reduction was linked to structural brain changes, such as larger lateral ventricles, reduced white matter volume, and decreased fractional anisotropy in critical white matter tracts, but not to cognitive performance. This suggests that ß band power reduction may serve as an early marker of vascular damage before the onset of cognitive symptoms. Conclusion: Our findings partially confirm our initial hypothesis by demonstrating a decrease in ß band power with increased vascular damage but not the anticipated increase in slow band power. The lack of correlation between the ßpow marker and cognitive performance suggests its potential utility in early identification of at-risk individuals for future cognitive impairment due to vascular origins. These results contribute to understanding the electrophysiological signatures of preclinical vascular damage and highlight the importance of MEG in detecting subtle brain changes associated with aging.
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Cerebrovascular damage from small vessel disease (SVD) occurs in healthy and pathological aging. SVD markers, such as white matter hyperintensities (WMH), are commonly found in individuals over 60 and increase in prevalence with age. WMHs are detectable on standard MRI by adhering to the STRIVE criteria. Currently, visual assessment scales are used in clinical and research scenarios but is time-consuming and has rater variability, limiting its practicality. Addressing this issue, our study aimed to determine the most precise WMH segmentation software, offering insights into methodology and usability to balance clinical precision with practical application. This study employed a dataset comprising T1, FLAIR, and DWI images from 300 cognitively healthy older adults. WMHs in this cohort were evaluated using four automated neuroimaging tools: Lesion Prediction Algorithm (LPA) and Lesion Growth Algorithm (LGA) from Lesion Segmentation Tool (LST), Sequence Adaptive Multimodal Segmentation (SAMSEG), and Brain Intensity Abnormalities Classification Algorithm (BIANCA). Additionally, clinicians manually segmented WMHs in a subsample of 45 participants to establish a gold standard. The study assessed correlations with the Fazekas scale, algorithm performance, and the influence of WMH volume on reliability. Results indicated that supervised algorithms were superior, particularly in detecting small WMHs, and can improve their consistency when used in parallel with unsupervised tools. The research also proposed a biomarker for moderate vascular damage, derived from the top 95th percentile of WMH volume in healthy individuals aged 50 to 60. This biomarker effectively differentiated subgroups within the cohort, correlating with variations in brain structure and behavior.
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White matter hyperintensities of vascular origin (WMH) are commonly found in individuals over 60 and increase in prevalence with age. The significance of WMH is well-documented, with strong associations with cognitive impairment, risk of stroke, mental health, and brain structure deterioration. Consequently, careful monitoring is crucial for the early identification and management of individuals at risk. Luckily, WMH are detectable and quantifiable on standard MRI through visual assessment scales, but it is time-consuming and has high rater variability. Addressing this issue, the main aim of our study is to decipher the utility of quantitative measures of WMH, assessed with automatic tools, in establishing risk profiles for cerebrovascular deterioration. For this purpose, first, we work to determine the most precise WMH segmentation open access tool compared to clinician manual segmentations (LST-LPA, LST-LGA, SAMSEG, and BIANCA), offering insights into methodology and usability to balance clinical precision with practical application. The results indicated that supervised algorithms (LST-LPA and BIANCA) were superior, particularly in detecting small WMH, and can improve their consistency when used in parallel with unsupervised tools (LST-LGA and SAMSEG). Additionally, to investigate the behavior and real clinical utility of these tools, we tested them in a real-world scenario (N = 300; age > 50 y.o. and MMSE > 26), proposing an imaging biomarker for moderate vascular damage. The results confirmed its capacity to effectively identify individuals at risk comparing the cognitive and brain structural profiles of cognitively healthy adults above and below the resulted threshold.
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Envejecimiento , Imagen por Resonancia Magnética , Sustancia Blanca , Humanos , Anciano , Masculino , Femenino , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Sustancia Blanca/irrigación sanguínea , Envejecimiento/fisiología , Envejecimiento/patología , Algoritmos , Persona de Mediana Edad , Anciano de 80 o más Años , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/irrigación sanguínea , Trastornos Cerebrovasculares/diagnóstico por imagenRESUMEN
Mild cognitive impairment (MCI) has been frequently interpreted as a transitional phase between healthy cognitive aging and dementia, particularly of the Alzheimer's disease (AD) type. Of note, few studies explored that transition from a multifactorial perspective, taking into consideration the effect of basic factors such as biological sex. In the present study 96 subjects with MCI (37 males and 59 females) were followed-up and divided into two subgroups according to their clinical outcome: "progressive" MCI (pMCI = 41), if they fulfilled the diagnostic criteria for AD at the end of follow-up; and "stable" MCI (sMCI = 55), if they remained with the initial diagnosis. Different markers were combined to characterize sex differences between groups, including magnetoencephalography recordings, cognitive performance, and brain volumes derived from magnetic resonance imaging. Results indicated that the pMCI group exhibited higher low-frequency activity, lower scores in neuropsychological tests and reduced brain volumes than the sMCI group, being these measures significantly correlated. When sex was considered, results revealed that this pattern was mainly due to the influence of the females' sample. Overall, females exhibited lower cognitive scores and reduced brain volumes. More interestingly, females in the pMCI group showed an increased theta activity that correlated with a more abrupt reduction of cognitive and volumetric scores as compared with females in the sMCI group and with males in the pMCI group. These findings suggest that females' brains might be more vulnerable to the effects of AD pathology, since regardless of age, they showed signs of more pronounced deterioration than males.
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Enfermedad de Alzheimer , Humanos , Masculino , Femenino , Caracteres Sexuales , Progresión de la Enfermedad , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patologíaRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0283169.].
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INTRODUCTION: Large Language Models (LLMs), such as the GPT model family from OpenAI, have demonstrated transformative potential across various fields, especially in medicine. These models can understand and generate contextual text, adapting to new tasks without specific training. This versatility can revolutionize clinical practices by enhancing documentation, patient interaction, and decision-making processes. In oncology, LLMs offer the potential to significantly improve patient care through the continuous monitoring of chemotherapy-induced toxicities, which is a task that is often unmanageable for human resources alone. However, existing research has not sufficiently explored the accuracy of LLMs in identifying and assessing subjective toxicities based on patient descriptions. This study aims to fill this gap by evaluating the ability of LLMs to accurately classify these toxicities, facilitating personalized and continuous patient care. METHODS: This comparative pilot study assessed the ability of an LLM to classify subjective toxicities from chemotherapy. Thirteen oncologists evaluated 30 fictitious cases created using expert knowledge and OpenAI's GPT-4. These evaluations, based on the CTCAE v.5 criteria, were compared to those of a contextualized LLM model. Metrics such as mode and mean of responses were used to gauge consensus. The accuracy of the LLM was analyzed in both general and specific toxicity categories, considering types of errors and false alarms. The study's results are intended to justify further research involving real patients. RESULTS: The study revealed significant variability in oncologists' evaluations due to the lack of interaction with fictitious patients. The LLM model achieved an accuracy of 85.7% in general categories and 64.6% in specific categories using mean evaluations with mild errors at 96.4% and severe errors at 3.6%. False alarms occurred in 3% of cases. When comparing the LLM's performance to that of expert oncologists, individual accuracy ranged from 66.7% to 89.2% for general categories and 57.0% to 76.0% for specific categories. The 95% confidence intervals for the median accuracy of oncologists were 81.9% to 86.9% for general categories and 67.6% to 75.6% for specific categories. These benchmarks highlight the LLM's potential to achieve expert-level performance in classifying chemotherapy-induced toxicities. DISCUSSION: The findings demonstrate that LLMs can classify subjective toxicities from chemotherapy with accuracy comparable to expert oncologists. The LLM achieved 85.7% accuracy in general categories and 64.6% in specific categories. While the model's general category performance falls within expert ranges, specific category accuracy requires improvement. The study's limitations include the use of fictitious cases, lack of patient interaction, and reliance on audio transcriptions. Nevertheless, LLMs show significant potential for enhancing patient monitoring and reducing oncologists' workload. Future research should focus on the specific training of LLMs for medical tasks, conducting studies with real patients, implementing interactive evaluations, expanding sample sizes, and ensuring robustness and generalization in diverse clinical settings. CONCLUSIONS: This study concludes that LLMs can classify subjective toxicities from chemotherapy with accuracy comparable to expert oncologists. The LLM's performance in general toxicity categories is within the expert range, but there is room for improvement in specific categories. LLMs have the potential to enhance patient monitoring, enable early interventions, and reduce severe complications, improving care quality and efficiency. Future research should involve specific training of LLMs, validation with real patients, and the incorporation of interactive capabilities for real-time patient interactions. Ethical considerations, including data accuracy, transparency, and privacy, are crucial for the safe integration of LLMs into clinical practice.
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The cognitive performance of the crew has a major impact on mission safety and success in space flight. Monitoring of cognitive performance during long-duration space flight therefore is of paramount importance and can be performed using compact state-of-the-art mobile EEG. However, signal quality of EEG may be compromised due to the vicinity to various electronic devices and constant movements. We compare noise characteristics between in-flight extraterrestrial microgravity and ground-level terrestrial electroencephalography (EEG) recordings. EEG data recordings from either aboard International Space Station (ISS) or on earth's surface, utilizing three EEG amplifiers and two electrode types, were compared. In-flight recordings showed noise level of an order of magnitude lower when compared to pre- and post-flight ground-level recordings with the same EEG system. Noise levels between ground-level recordings with actively shielded cables, and in-flight recordings without shielded cables, were similar. Furthermore, noise level characteristics of shielded ground-level EEG recordings, using wet and dry electrodes, and in-flight EEG recordings were similar. Actively shielded mobile dry EEG systems will support neuroscientific research and neurocognitive monitoring during spaceflight, especially during long-duration space missions.
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Vuelo Espacial , Ingravidez , Electroencefalografía , ElectrodosRESUMEN
Delayed recall (DR) impairment is one of the most significant predictive factors in defining the progression to Alzheimer's disease (AD). Changes in brain functional connectivity (FC) could accompany this decline in the DR performance even in a resting state condition from the preclinical stages to the diagnosis of AD itself, so the characterization of the relationship between the two phenomena has attracted increasing interest. Another aspect to contemplate is the potential moderator role of the APOE genotype in this association, considering the evidence about their implication for the disease. 379 subjects (118 mild cognitive impairment (MCI) and 261 cognitively intact (CI) individuals) underwent an extensive evaluation, including MEG recording. Applying cluster-based permutation test, we identified a cluster of differences in FC and studied which connections drove such an effect in DR. The moderation effect of APOE genotype between FC results and delayed recall was evaluated too. Higher FC in beta band in the right occipital region is associated with lower DR scores in both groups. A significant anteroposterior link emerged in the seed-based analysis with higher values in MCI. Moreover, APOE genotype appeared as a moderator between beta FC and DR performance only in the CI group. An increased beta FC in the anteroposterior brain region appears to be associated with lower memory performance in MCI. This finding could help discriminate the pattern of the progression of healthy aging to MCI and the relation between resting state and memory performance.
Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Memoria Episódica , Humanos , Encéfalo , Apolipoproteínas ERESUMEN
Cerebrovascular disease is responsible for up to 20% of cases of dementia worldwide, but also it is a major comorbid contributor to the progression of other neurodegenerative diseases, like Alzheimer's disease. White matter hyperintensities (WMH) are the most prevalent imaging marker in cerebrovascular disease. The presence and progression of WMH in the brain have been associated with general cognitive impairment and the risk to develop all types of dementia. The aim of this piece of work is the assessment of brain functional differences in an MCI population based on the WMH volume. One-hundred and twenty-nine individuals with mild cognitive impairment (MCI) underwent a neuropsychological evaluation, MRI assessment (T1 and Flair), and MEG recordings (5 min of eyes closed resting state). Those participants were further classified into vascular MCI (vMCI; n = 61, mean age 75 ± 4 years, 35 females) or non-vascular MCI (nvMCI; n = 56, mean age 72 ± 5 years, 36 females) according to their WMH total volume, assessed with an automatic detection toolbox, LST (SPM12). We used a completely data-driven approach to evaluate the differences in the power spectra between the groups. Interestingly, three clusters emerged: One cluster with widespread larger theta power and two clusters located in both temporal regions with smaller beta power for vMCI compared to nvMCI. Those power signatures were also associated with cognitive performance and hippocampal volume. Early identification and classification of dementia pathogenesis is a crucially important goal for the search for more effective management approaches. These findings could help to understand and try to palliate the contribution of WMH to particular symptoms in mixed dementia progress.