Alteraciones neuropsicológicas y daño cerebral en la infancia y adolescencia asociados al nacimiento prematuro

Prematurity is defined by the World Health Organization (WHO, 1977) as a delivery occurring before 37 completed weeks of gestation. White matter (WM) abnormalities and periventricular leukomalacia (PVL) are the most prominent pathologies in the preterm neonate. Compared with their term-peers, children born preterm have lower intelligence quotient (IQ) scores, although within the normal range. Moreover, domain-specific measures of neuropsychological abilities such as executive functions, visuoperceptual and linguistic skills are often impaired. Preterm children with PVL have a similar profile, with lower IQ scores and poorer executive functions, mental calculation and visuoperceptual skills than controls. Cerebral structural gray matter (GM) abnormalities that might contribute to the poor performance of preterm samples are localized in the frontal, parietal, temporal and occipital lobes. The cerebellum and deep gray matter structures such as the caudate nuclei, the thalami and the hippocampus are also altered. Over the past few years, magnetic resonance imaging and neuropathological studies have shown that, in addition to the classical WM injury seen in preterm samples with PVL, cortical and subcortical GM injury may also contribute to the impaired cognitive performance.La prematuridad es definida por la Organización Mundial de la Salud (OMS, 1977) como el parto que ocurre antes de las 37 semanas de gestación. La alteración de la sustancia blanca (SB) es la principal característica de daño cerebral y la leucomalacia periventricular (LPV) es el hallazgo patológico más común en estudios de resonancia magnética Los niños nacidos prematuros comparados con los niños nacidos a término presentan un cociente de inteligencia (CI) con puntuaciones menores pero dentro de la normalidad. Las funciones neuropsicológicas específicas más afectadas son las ejecutivas, visuo-perceptivas y lingüísticas. Los niños prematuros con LPV, también muestran puntuaciones más bajas en el CI, en las funciones ejecutivas, en el cálculo mental y en las capacidades visuoperceptivas. Las alteraciones cerebrales estructurales de sustancia gris (SG) que pueden contribuir a una peor ejecución cognitiva en estas muestras de prematuros implican regiones en los lóbulos cerebrales temporal, parietal, frontal y occipital. Además, el cerebelo y diversos núcleos grises subcorticales tales como el núcleo caudado, el tálamo y el hipocampo están también afectados. En los últimos años, los estudios de resonancia magnética y neuropatológicos, están demostrando que además de la alteración clásica de SB, los niños prematuros con LPV presentan daño en la SG tanto cortical como subcortical a los cuales se les atribuye una implicación directa en la peor ejecución cognitiva

Alteraciones neuropsicológicas y daño cerebral en la infancia y adolescencia asociados al nacimiento prematuro

Prematurity is defined by the World Health Organization (WHO, 1977) as a delivery occurring before 37 completed weeks of gestation. White matter (WM) abnormalities and periventricular leukomalacia (PVL) are the most prominent pathologies in the preterm neonate. Compared with their term-peers, children born preterm have lower intelligence quotient (IQ) scores, although within the normal range. Moreover, domain-specific measures of neuropsychological abilities such as executive functions, visuoperceptual and linguistic skills are often impaired. Preterm children with PVL have a similar profile, with lower IQ scores and poorer executive functions, mental calculation and visuoperceptual skills than controls. Cerebral structural gray matter (GM) abnormalities that might contribute to the poor performance of preterm samples are localized in the frontal, parietal, temporal and occipital lobes. The cerebellum and deep gray matter structures such as the caudate nuclei, the thalami and the hippocampus are also altered. Over the past few years, magnetic resonance imaging and neuropathological studies have shown that, in addition to the classical WM injury seen in preterm samples with PVL, cortical and subcortical GM injury may also contribute to the impaired cognitive performance.  La prematuridad es definida por la Organización Mundial de la Salud (OMS, 1977) como el parto que ocurre antes de las 37 semanas de gestación. La alteración de la sustancia blanca (SB) es la principal característica de daño cerebral y la leucomalacia periventricular (LPV) es el hallazgo patológico más común en estudios de resonancia magnética Los niños nacidos prematuros comparados con los niños nacidos a término presentan un cociente de inteligencia (CI) con puntuaciones menores pero dentro de la normalidad. Las funciones neuropsicológicas específicas más afectadas son las ejecutivas visuo-perceptivas y lingüísticas. Los niños prematuros con LPV, también muestran puntuaciones más bajas en el CI, en las funciones ejecutivas, en el cálculo mental y en las capacidades visuoperceptivas. Las alteraciones cerebrales estructurales de sustancia gris (SG) que pueden contribuir a una peor ejecución cognitiva en estas muestras de prematuros implican regiones en los lóbulos cerebrales temporal, parietal, frontal y occipital. Además, el cerebelo y diversos núcleos grises subcorticales tales como el núcleo caudado, el tálamo y el hipocampo están también afectados. En los últimos años, los estudios de resonancia magnética y neuropatológicos, están demostrando que además de la alteración clásica de SB, los niños prematuros con LPV presentan daño en la SG tanto cortical como subcortical a los cuales se les atribuye una implicación directa en la peor ejecución cognitiva

Alteraciones neuropsicológicas en el alcoholismo crónico

El déficit neuropsicológico asociado al alcholismo abarca diversas funciones: memoria, razonamiento abstracto, solución de problemas y ha- bilidades perceptivo-motoras. Estructuralmente, los cambios cerebrales ob- servados con m i s frecuencia en la Tomografia Computarizada (TC) son la atrofia cerebral difusa y la dilatación ventricular. La dilatación ventri- cular es la medida de atrofia cerebral que m i s correlaciona con el déficit neuropsicológico. Desde ei punto de vista funcional, el flujo sanguineo ce- rebral repional muestra una reducción. esencialmente en los alcohólicos de más eda;. El deterioro cerebral y de funciones cognitivas esta' en relacion con varios factores: toxicidad directa del alcohol, déficit de tiamina, y dis- funciones hepáticas. Existe además una interacción entre la edad y las al- teraciones citadas. Añadir por ultimo que tanto los signos de atrofia en la TC, como la reducción de flujo sanguineo y los trastornos neuropsico- lógicos son parcialmente reversibles con la abstinencia. Palabras clave: Alcoholisme, neuropsicologia, tomografia compu- tarizada, flujo sanguineo cerebral

Perfil de memoria en el trastorno por déficit de atención con hiperactividad.

The objective of this study is to contribute to the establishment of a memory profile in subjects with attention deficit disorder with hyperactivity (ADHD). We examined fifty-one adolescents: 16 ADHD and 35 controls, aged between 14 and 16. Neuropsychological exploration included tests of short-term memory and of declarative and implicit (incidental and procedural) memory. Subjects with ADHD presented deficits in their mnesic abilities. These deficits do not involve all type of memory, but are selective. Declarative memory and, especially, short-term memory show higher deficits than implicit or non-declarative memory: incidental learning is preserved and procedural learning is similar to that obtained by control subjects, although this forn of learning presents more diflculties for ADHD subjects learning with a higher difficulty

Brain connectivity dynamics in cisgender and transmen people with gender incongruence before gender affirmative hormone treatment

Large-scale brain network interactions have been described between trans- and cis-gender binary identities. However, a temporal perspective of the brain's spontaneous fuctuations is missing. We investigated the functional connectivity dynamics in transmen with gender incongruence and its relationship with interoceptive awareness. We describe four states in native and meta-state spaces: (i) one state highly prevalent with sparse overall connections; (ii) a second with strong couplings mainly involving components of the salience, default, and executive control networks. Two states with global sparse connectivity but positive couplings (iii) within the sensorimotor network, and (iv) between salience network regions. Transmen had more dynamical fuidity than cismen, while cismen presented less meta-state fuidity and range dynamism than transmen and ciswomen. A positive association between attention regulation and fuidity and meta-state range dynamism was found in transmen. There exist gender diferences in the temporal brain dynamism, characterized by distinct interrelations of the salience network as catalyst interacting with other networks. We ofer a functional explanation from the neurodevelopmental cortical hypothesis of a gendered-self

Resting-state functional brain netwoks in Parkinson's disease

The network approach is increasingly being applied to the investigation of normal brain function and its impairment. In the present review, we introduce the main methodological approaches employed for the analysis of resting-state neuroimaging data in Parkinson's disease studies. We then summarize the results of recent studies that used a functional network perspective to evaluate the changes underlying different manifestations of Parkinson's disease, with an emphasis on its cognitive symptoms. Despite the variability reported by many studies, these methods show promise as tools for shedding light on the pathophysiological substrates of different aspects of Parkinson's disease, as well as for differential diagnosis, treatment monitoring and establishment of imaging biomarkers for more severe clinical outcomes

Visuospatial and visuoperceptual impairment in relation to global atrophy in Parkinson's disease

Parkinson’s disease (PD) patients differed from controls of similar age in visuospatial and visuoperceptual functions at diagnosis moment, and these deficits have been shown to be neuropsychological markers of evolution to dementia. The aim of this study was to relate these dysfunctions with measures of brain. The sample of this study consisted of 92 PD patients and 36 healthy subjects matched by age, sex and education. All subjects were evaluated with Judgment of Line Orientation, Visual Form Discrimination and Facial Recognition Tests and magnetic resonance imaging at 3 Tesla. We found significant differences between patients and controls in all three tests and in the mean of cortical thickness, gray matter volume and ventricular system. All visuospatial and visuoperceptual tests correlated with the measures of global atrophy suggesting that they are reflecting the brain degeneration associated to PD.Los pacientes con enfermedad de Parkinson (EP) comparados con controles de similar edad muestran alteraciones visuoespaciales y visuoperceptivas desde el momento del diagnóstico, y se ha demostrado que estas alteraciones actúan como marcadores neuropsicológicos de la evolución a demencia. El objetivo de este estudio es relacionar estas alteraciones con las medidas globales de atrofia cerebral. La muestra consta de 92 EP y 36 sujetos sanos emparejadospor edad, sexo y educación. Todos los sujetos fueron evaluados mediante el Judgment of Line Orientation, Visual Form Discrimination y Facial Recognition Test y se obtuvieron datos de neuroimagen estructural con un aparato de Resonancia Magnética de 3 tesla. Se observaron diferencias entreblos pacientes y los controles en los tres tests usados y en las medidas de grosor cortical total, volumen de sustancia gris y sistema ventricular. Todos los tests visuoespaciales y visuoperceptivos correlacionaron con medidas de atrofia global, lo cual sugiere que son indicadores útiles de la degeneración cerebral asociada a la EP

Structural and functional magnetic resonance imaging in isolated REM sleep behavior disorder: A systematic review of studies using neuroimaging software.

Isolated rapid eye movement sleep behavior disorder (iRBD) is a harbinger for developing clinical synucleinopathies. Magnetic resonance imaging (MRI) has been suggested as a tool for understanding the brain bases of iRBD and its evolution. This review systematically analyzed original full text articles on structural and functional MRI in patients with video-polysomnography-confirmed iRBD according to systematic procedures suggested by Reviews and Meta-analyses (PRISMA). The literature search was conducted via the PubMed database for articles related to structural and functional MRI in iRBD from 2000 to 2020. Investigations to date have been diverse in terms of methodology, but most agree that patients with iRBD have structural changes in deep gray matter nuclei, cortical gray matter atrophy, and disrupted functional connectivity within the basal ganglia, the cortico-striatal and cortico-cortical networks. Furthermore, there is evidence that MRI detects structural and functional brain changes associated with the motor and non-motor symptoms of iRBD. The current review highlights the need for larger multicenter and longitudinal studies, using complex approaches based on data-driven and unsupervised machine learning that will help to identify structural and functional patterns of brain degeneration. In turn, this may even allow for the prediction of subsequent phenoconversion from iRBD to the clinically defined synucleinopathie