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1.
Hum Brain Mapp ; 43(1): 452-469, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33570244

RESUMEN

Age has a major effect on brain volume. However, the normative studies available are constrained by small sample sizes, restricted age coverage and significant methodological variability. These limitations introduce inconsistencies and may obscure or distort the lifespan trajectories of brain morphometry. In response, we capitalized on the resources of the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) Consortium to examine age-related trajectories inferred from cross-sectional measures of the ventricles, the basal ganglia (caudate, putamen, pallidum, and nucleus accumbens), the thalamus, hippocampus and amygdala using magnetic resonance imaging data obtained from 18,605 individuals aged 3-90 years. All subcortical structure volumes were at their maximum value early in life. The volume of the basal ganglia showed a monotonic negative association with age thereafter; there was no significant association between age and the volumes of the thalamus, amygdala and the hippocampus (with some degree of decline in thalamus) until the sixth decade of life after which they also showed a steep negative association with age. The lateral ventricles showed continuous enlargement throughout the lifespan. Age was positively associated with inter-individual variability in the hippocampus and amygdala and the lateral ventricles. These results were robust to potential confounders and could be used to examine the functional significance of deviations from typical age-related morphometric patterns.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Cuerpo Estriado/anatomía & histología , Hipocampo/anatomía & histología , Desarrollo Humano/fisiología , Neuroimagen , Tálamo/anatomía & histología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Amígdala del Cerebelo/diagnóstico por imagen , Niño , Preescolar , Cuerpo Estriado/diagnóstico por imagen , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Tálamo/diagnóstico por imagen , Adulto Joven
2.
Hum Brain Mapp ; 42(14): 4597-4610, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34184808

RESUMEN

Putative MRI markers of iron in deep gray matter have demonstrated age related changes during discrete periods of healthy childhood or adulthood, but few studies have included subjects across the lifespan. This study reports both transverse relaxation rate (R2*) and quantitative susceptibility mapping (QSM) of four primary deep gray matter regions (thalamus, putamen, caudate, and globus pallidus) in 498 healthy individuals aged 5-90 years. In the caudate, putamen, and globus pallidus, increases of QSM and R2* were steepest during childhood continuing gradually throughout adulthood, except caudate susceptibility which reached a plateau in the late 30s. The thalamus had a unique profile with steeper changes of R2* (reflecting additive effects of myelin and iron) than QSM during childhood, both reaching a plateau in the mid-30s to early 40s and decreasing thereafter. There were no hemispheric or sex differences for any region. Notably, both R2* and QSM values showed more inter-subject variability with increasing age from 5 to 90 years, potentially reflecting a common starting point in iron/myelination during childhood that diverges as a result of lifestyle and genetic factors that accumulate with age.


Asunto(s)
Variación Biológica Individual , Cuerpo Estriado , Sustancia Gris , Desarrollo Humano , Imagen por Resonancia Magnética , Tálamo , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/diagnóstico por imagen , Femenino , Sustancia Gris/anatomía & histología , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Tálamo/anatomía & histología , Tálamo/diagnóstico por imagen , Adulto Joven
3.
Hum Brain Mapp ; 42(6): 1583-1593, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33528897

RESUMEN

Individual differences in subcortical brain volumes are highly heritable. Previous studies have identified genetic variants that underlie variation in subcortical volumes in adults. We tested whether those previously identified variants also affect subcortical regions during infancy and early childhood. The study was performed within the Generation R study, a prospective birth cohort. We calculated polygenic scores based on reported GWAS for volumes of the accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen, and thalamus. Participants underwent cranial ultrasound around 7 weeks of age (range: 3-20), and we obtained metrics for the gangliothalamic ovoid, a predecessor of the basal ganglia. Furthermore, the children participated in a magnetic resonance imaging (MRI) study around the age of 10 years (range: 9-12). A total of 340 children had complete data at both examinations. Polygenic scores primarily associated with their corresponding volumes at 10 years of age. The scores also moderately related to the diameter of the gangliothalamic ovoid on cranial ultrasound. Mediation analysis showed that the genetic influence on subcortical volumes at 10 years was only mediated for 16.5-17.6% of the total effect through the gangliothalamic ovoid diameter at 7 weeks of age. Combined, these findings suggest that previously identified genetic variants in adults are relevant for subcortical volumes during early life, and that they affect both prenatal and postnatal development of the subcortical regions.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Tronco Encefálico/anatomía & histología , Cuerpo Estriado/anatomía & histología , Estudio de Asociación del Genoma Completo , Herencia Multifactorial/genética , Tálamo/anatomía & histología , Amígdala del Cerebelo/diagnóstico por imagen , Variación Biológica Poblacional , Cohorte de Nacimiento , Tronco Encefálico/diagnóstico por imagen , Niño , Cuerpo Estriado/diagnóstico por imagen , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Tálamo/diagnóstico por imagen , Ultrasonografía
4.
Hum Brain Mapp ; 41(1): 162-171, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31571360

RESUMEN

Low socioeconomic status (SES) is associated with a higher probability of multiple exposures (e.g., neighborhood violence, poor nutrition, housing instability, air pollution, and insensitive caregiving) known to affect structural development of subcortical brain regions that subserve threat and reward processing, however, few studies have examined the relationship between SES and such subcortical structures in adolescents. We examined SES variations in volume and surface morphometry of subcortical regions. The sample comprised 256 youth in eighth grade (mean age = 13.9 years), in whom high dimensional deformation mapping of structural 3T magnetic resonance imaging scans was performed. Vertex-wise linear regression analyses examined associations between income to poverty ratio and surfaces of the hippocampus, amygdala, thalamus, caudate, putamen, nucleus accumbens and pallidum, with the covariates age, pubertal status, and intracranial volume. Given sex differences in pubertal development and subcortical maturation at this age, the analyses were stratified by sex. Among males, who at this age average an earlier pubertal stage than females, the relationship between SES and local shape variation in subcortical regions was almost entirely positive. For females, the relationship between SES and local shape variation was negative. Racial identity was associated with SES in our sample, however supplementary analyses indicated that most of the associations between SES and subcortical structure were independent of it. Although these cross-sectional results are not definitive, they are consistent with a scenario where low SES delays structural maturation of subcortical regions involved with threat and reward processing. Future longitudinal studies are needed to test this hypothesis.


Asunto(s)
Desarrollo del Adolescente/fisiología , Amígdala del Cerebelo/anatomía & histología , Cuerpo Estriado/anatomía & histología , Hipocampo/anatomía & histología , Clase Social , Tálamo/anatomía & histología , Adolescente , Amígdala del Cerebelo/diagnóstico por imagen , Cuerpo Estriado/diagnóstico por imagen , Estudios Transversales , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Masculino , Factores Sexuales , Tálamo/diagnóstico por imagen
5.
Commun Biol ; 2: 153, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31069263

RESUMEN

Altered expression of GABA receptors (GABAARs) has been implicated in neurological and psychiatric disorders, but limited information about region-specific GABAAR subunit expression in healthy human brains, heteromeric assembly of major isoforms, and their collective organization across healthy individuals, are major roadblocks to understanding their role in non-physiological states. Here, by using microarray and RNA-Seq datasets-from single cell nuclei to global brain expression-from the Allen Institute, we find that transcriptional expression of GABAAR subunits is anatomically organized according to their neurodevelopmental origin. The data show a combination of complementary and mutually-exclusive expression patterns that delineate major isoforms, and which is highly stereotypical across brains from control donors. We summarize the region-specific signature of GABAR subunits per subject and its variability in a control population sample that can be used as a reference for remodeling changes during homeostatic rearrangements of GABAAR subunits after physiological, pharmacological or pathological challenges.


Asunto(s)
Encéfalo/metabolismo , Subunidades de Proteína/genética , Receptores de GABA-A/genética , Transcriptoma , Adulto , Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/metabolismo , Encéfalo/anatomía & histología , Corteza Cerebral/anatomía & histología , Corteza Cerebral/metabolismo , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/metabolismo , Conjuntos de Datos como Asunto , Femenino , Perfilación de la Expresión Génica , Hipocampo/anatomía & histología , Hipocampo/metabolismo , Humanos , Hipotálamo/anatomía & histología , Hipotálamo/metabolismo , Masculino , Mesencéfalo/anatomía & histología , Mesencéfalo/metabolismo , Persona de Mediana Edad , Especificidad de Órganos , Filogenia , Subunidades de Proteína/clasificación , Subunidades de Proteína/metabolismo , Receptores de GABA-A/clasificación , Receptores de GABA-A/metabolismo
6.
Neuroscience ; 402: 104-115, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30615913

RESUMEN

Ample evidence suggests that consolidation of the memory trace associated with a newly acquired motor sequence is supported by thalamo-cortical spindle activity during subsequent sleep, as well as functional changes in a distributed cortico-striatal network. To date, however, no studies have investigated whether the structural white matter connections between these regions affect motor sequence memory consolidation in relation with sleep spindles. Here, we used diffusion weighted imaging (DWI) tractography to reconstruct the major fascicles of the cortico-striato-pallido-thalamo-cortical loop in both young and older participants who were trained on an explicit finger sequence learning task before and after a daytime nap. Thereby, this allowed us to examine whether post-learning sleep spindles measured using polysomnographic recordings interact with consolidation processes and this specific neural network. Our findings provide evidence corroborating the critical role of NREM2 thalamo-cortical sleep spindles in motor sequence memory consolidation, and show that the post-learning changes in these neurophysiological events relate specifically to white matter characteristics in thalamo-cortical fascicles. Moreover, we demonstrate that microstructure along this fascicle relates indirectly to offline gains in performance through an increase of spindle density over motor-related cortical areas. These results suggest that the integrity of thalamo-cortical projections, via their impact on sleep spindle generation, may represent one of the critical mechanisms modulating the expression of sleep-dependent offline gains following motor sequence learning in healthy adults.


Asunto(s)
Consolidación de la Memoria/fisiología , Corteza Motora/fisiología , Destreza Motora/fisiología , Sueño , Tálamo/fisiología , Sustancia Blanca/fisiología , Adulto , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/fisiología , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Electroencefalografía , Humanos , Persona de Mediana Edad , Actividad Motora , Corteza Motora/anatomía & histología , Vías Nerviosas/anatomía & histología , Vías Nerviosas/fisiología , Polisomnografía , Tálamo/anatomía & histología , Sustancia Blanca/anatomía & histología , Adulto Joven
7.
Hum Brain Mapp ; 39(12): 4663-4677, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30004604

RESUMEN

Physiological aging affects brain structure and function impacting morphology, connectivity, and performance. However, whether some brain connectivity metrics might reflect the age of an individual is still unclear. Here, we collected brain images from healthy participants (N = 155) ranging from 10 to 80 years to build functional (resting state) and structural (tractography) connectivity matrices, both data sets combined to obtain different connectivity features. We then calculated the brain connectome age-an age estimator resulting from a multi-scale methodology applied to the structure-function connectome, and compared it to the chronological age (ChA). Our results were twofold. First, we found that aging widely affects the connectivity of multiple structures, such as anterior cingulate and medial prefrontal cortices, basal ganglia, thalamus, insula, cingulum, hippocampus, parahippocampus, occipital cortex, fusiform, precuneus, and temporal pole. Second, we found that the connectivity between basal ganglia and thalamus to frontal areas, also known as the fronto-striato-thalamic (FST) circuit, makes the major contribution to age estimation. In conclusion, our results highlight the key role played by the FST circuit in the process of healthy aging. Notably, the same methodology can be generally applied to identify the structural-functional connectivity patterns correlating to other biomarkers than ChA.


Asunto(s)
Envejecimiento/fisiología , Conectoma/métodos , Cuerpo Estriado , Imagen de Difusión Tensora/métodos , Red Nerviosa , Corteza Prefrontal , Tálamo , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/fisiología , Humanos , Persona de Mediana Edad , Red Nerviosa/anatomía & histología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología , Corteza Prefrontal/anatomía & histología , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Tálamo/anatomía & histología , Tálamo/diagnóstico por imagen , Tálamo/fisiología , Adulto Joven
8.
Med Image Anal ; 46: 189-201, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29574399

RESUMEN

Surface mapping methods play an important role in various brain imaging studies from tracking the maturation of adolescent brains to mapping gray matter atrophy patterns in Alzheimer's disease. Popular surface mapping approaches based on spherical registration, however, have inherent numerical limitations when severe metric distortions are present during the spherical parameterization step. In this paper, we propose a novel computational framework for intrinsic surface mapping in the Laplace-Beltrami (LB) embedding space based on Riemannian metric optimization on surfaces (RMOS). Given a diffeomorphism between two surfaces, an isometry can be defined using the pullback metric, which in turn results in identical LB embeddings from the two surfaces. The proposed RMOS approach builds upon this mathematical foundation and achieves general feature-driven surface mapping in the LB embedding space by iteratively optimizing the Riemannian metric defined on the edges of triangular meshes. At the core of our framework is an optimization engine that converts an energy function for surface mapping into a distance measure in the LB embedding space, which can be effectively optimized using gradients of the LB eigen-system with respect to the Riemannian metrics. In the experimental results, we compare the RMOS algorithm with spherical registration using large-scale brain imaging data, and show that RMOS achieves superior performance in the prediction of hippocampal subfields and cortical gyral labels, and the holistic mapping of striatal surfaces for the construction of a striatal connectivity atlas from substantia nigra.


Asunto(s)
Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Algoritmos , Corteza Cerebral/anatomía & histología , Corteza Cerebral/diagnóstico por imagen , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/diagnóstico por imagen , Hipocampo/anatomía & histología , Hipocampo/diagnóstico por imagen , Humanos , Reproducibilidad de los Resultados
9.
Neuroimage ; 170: 456-470, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28450139

RESUMEN

This study investigates a 3D and fully convolutional neural network (CNN) for subcortical brain structure segmentation in MRI. 3D CNN architectures have been generally avoided due to their computational and memory requirements during inference. We address the problem via small kernels, allowing deeper architectures. We further model both local and global context by embedding intermediate-layer outputs in the final prediction, which encourages consistency between features extracted at different scales and embeds fine-grained information directly in the segmentation process. Our model is efficiently trained end-to-end on a graphics processing unit (GPU), in a single stage, exploiting the dense inference capabilities of fully CNNs. We performed comprehensive experiments over two publicly available datasets. First, we demonstrate a state-of-the-art performance on the ISBR dataset. Then, we report a large-scale multi-site evaluation over 1112 unregistered subject datasets acquired from 17 different sites (ABIDE dataset), with ages ranging from 7 to 64 years, showing that our method is robust to various acquisition protocols, demographics and clinical factors. Our method yielded segmentations that are highly consistent with a standard atlas-based approach, while running in a fraction of the time needed by atlas-based methods and avoiding registration/normalization steps. This makes it convenient for massive multi-site neuroanatomical imaging studies. To the best of our knowledge, our work is the first to study subcortical structure segmentation on such large-scale and heterogeneous data.


Asunto(s)
Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/diagnóstico por imagen , Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Tálamo/anatomía & histología , Tálamo/diagnóstico por imagen , Adolescente , Adulto , Trastorno del Espectro Autista/diagnóstico por imagen , Trastorno del Espectro Autista/patología , Niño , Conjuntos de Datos como Asunto , Humanos , Persona de Mediana Edad , Adulto Joven
10.
Neuroimage ; 170: 182-198, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28259781

RESUMEN

Accurate automated quantification of subcortical structures is a greatly pursued endeavour in neuroimaging. In an effort to establish the validity and reliability of these methods in defining the striatum, globus pallidus, and thalamus, we investigated differences in volumetry between manual delineation and automated segmentations derived by widely used FreeSurfer and FSL packages, and a more recent segmentation method, the MAGeT-Brain algorithm. In a first set of experiments, the basal ganglia and thalamus of thirty subjects (15 first episode psychosis [FEP], 15 controls) were manually defined and compared to the labels generated by the three automated methods. Our results suggest that all methods overestimate volumes compared to the manually derived "gold standard", with the least pronounced differences produced using MAGeT. The least between-method variability was noted for the striatum, whereas marked differences between manual segmentation and MAGeT compared to FreeSurfer and FSL emerged for the globus pallidus and thalamus. Correlations between manual segmentation and automated methods were strongest for MAGeT (range: 0.51 to 0.92; p<0.01, corrected), whereas FreeSurfer and FSL showed moderate to strong Pearson correlations (range 0.44-0.86; p<0.05, corrected), with the exception of FreeSurfer pallidal (r=0.31, p=0.10) and FSL thalamic segmentations (r=0.37, p=0.051). Bland-Altman plots highlighted a tendency for greater volumetric differences between manual labels and automated methods at the lower end of the distribution (i.e. smaller structures), which was most prominent for bilateral thalamus across automated pipelines, and left globus pallidus for FSL. We then went on to examine volume and shape of the basal ganglia structures using automated techniques in 135 FEP patients and 88 controls. The striatum and globus pallidus were significantly larger in FEP patients compared to controls bilaterally, irrespective of the method used. MAGeT-Brain was more sensitive to shape-based group differences, and uncovered widespread surface expansions in the striatum and globus pallidus bilaterally in FEP patients compared to controls, and surface contractions in bilateral thalamus (FDR-corrected). By contrast, after using a recommended cluster-wise thresholding method, FSL only detected differences in the right ventral striatum (FEP>Control) and one cluster of the left thalamus (Control>FEP). These results suggest that different automated pipelines segment subcortical structures with varying degrees of variability compared to manual methods, with particularly pronounced differences found with FreeSurfer and FSL for the globus pallidus and thalamus.


Asunto(s)
Cuerpo Estriado/diagnóstico por imagen , Globo Pálido/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/normas , Imagen por Resonancia Magnética/normas , Neuroimagen/normas , Trastornos Psicóticos/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Adulto , Cuerpo Estriado/anatomía & histología , Femenino , Globo Pálido/anatomía & histología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Neuroimagen/métodos , Trastornos Psicóticos/patología , Reproducibilidad de los Resultados , Tálamo/anatomía & histología , Adulto Joven
11.
Sci Rep ; 7(1): 7608, 2017 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-28790376

RESUMEN

The cortico-striatal-thalamo-cortical (CSTC) pathway is a brain circuit that controls movement execution, habit formation and reward. Hyperactivity in the CSTC pathway is involved in obsessive compulsive disorder (OCD), a neuropsychiatric disorder characterized by the execution of repetitive involuntary movements. The striatum shapes the activity of the CSTC pathway through the coordinated activation of two classes of medium spiny neurons (MSNs) expressing D1 or D2 dopamine receptors. The exact mechanisms by which balanced excitation/inhibition (E/I) of these cells controls the network dynamics of the CSTC pathway remain unclear. Here we use non-linear modeling of neuronal activity and bifurcation theory to investigate how global and local changes in E/I of MSNs regulate the activity of the CSTC pathway. Our findings indicate that a global and proportionate increase in E/I pushes the system to states of generalized hyper-activity throughout the entire CSTC pathway. Certain disproportionate changes in global E/I trigger network oscillations. Local changes in the E/I of MSNs generate specific oscillatory behaviors in MSNs and in the CSTC pathway. These findings indicate that subtle changes in the relative strength of E/I of MSNs can powerfully control the network dynamics of the CSTC pathway in ways that are not easily predicted by its synaptic connections.


Asunto(s)
Corteza Cerebral/fisiología , Cuerpo Estriado/fisiología , Excitabilidad Cortical/fisiología , Inhibición Neural/fisiología , Redes Neurales de la Computación , Transmisión Sináptica/fisiología , Tálamo/fisiología , Animales , Corteza Cerebral/anatomía & histología , Corteza Cerebral/citología , Conectoma , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/citología , Neuronas GABAérgicas/citología , Neuronas GABAérgicas/metabolismo , Ácido Glutámico/metabolismo , Humanos , Receptores Dopaminérgicos/metabolismo , Recompensa , Roedores , Especificidad de la Especie , Sinapsis/fisiología , Tálamo/anatomía & histología , Tálamo/citología , Ácido gamma-Aminobutírico/metabolismo
12.
Hum Brain Mapp ; 38(11): 5519-5534, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28752565

RESUMEN

BACKGROUND: Abnormalities in dopamine (DA) and brain morphology are observed in several neuropsychiatric disorders. However, it is not fully understood how these abnormalities may relate to one another. For such in vivo findings to be used as biomarkers for neuropsychiatric disease, it must be understood how variability in DA relates to brain structure under healthy conditions. We explored how the availability of striatal DA D2/3 receptors (D2/3 R) is related to the volume of subcortical brain structures in a sample of healthy humans. Differences in D2/3 R availability measured with an antagonist radiotracer ([11 C]-raclopride) versus an agonist radiotracer ([11 C]-(+)-PHNO) were examined. METHODS: Data from 62 subjects scanned with [11 C]-raclopride (mean age = 38.98 ± 14.45; 23 female) and 68 subjects scanned with [11 C]-(+)-PHNO (mean age = 38.54 ± 14.59; 25 female) were used. Subcortical volumes were extracted from T1-weighted images using the Multiple Automatically Generated Templates (MAGeT-Brain) algorithm. Partial correlations were used controlling for age, gender, and total brain volume. RESULTS: For [11 C]-(+)-PHNO, ventral caudate volumes were positively correlated with BPND in the dorsal caudate and globus pallidus (GP). Ventral striatum (VS) volumes were positively correlated with BPND in the VS. With [11 C]-raclopride, BPND in the VS was negatively correlated with subiculum volume of the hippocampus. Moreover, BPND in the GP was negatively correlated with the volume of the lateral posterior nucleus of the thalamus. CONCLUSION: Findings are purely exploratory and presented corrected and uncorrected for multiple comparisons. We hope they will help inform the interpretation of future PET studies where concurrent changes in D2/3 R and brain morphology are observed. Hum Brain Mapp 38:5519-5534, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Cuerpo Estriado/metabolismo , Hipocampo/diagnóstico por imagen , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Tálamo/diagnóstico por imagen , Adulto , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/diagnóstico por imagen , Femenino , Hipocampo/anatomía & histología , Humanos , Imagen por Resonancia Magnética , Masculino , Tamaño de los Órganos , Oxazinas , Tomografía de Emisión de Positrones , Racloprida , Radiofármacos , Tálamo/anatomía & histología
13.
Proc Natl Acad Sci U S A ; 113(34): 9653-8, 2016 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-27512040

RESUMEN

Fluctuations in resting-state functional connectivity occur but their behavioral significance remains unclear, largely because correlating behavioral state with dynamic functional connectivity states (DCS) engages probes that disrupt the very behavioral state we seek to observe. Observing spontaneous eyelid closures following sleep deprivation permits nonintrusive arousal monitoring. During periods of low arousal dominated by eyelid closures, sliding-window correlation analysis uncovered a DCS associated with reduced within-network functional connectivity of default mode and dorsal/ventral attention networks, as well as reduced anticorrelation between these networks. Conversely, during periods when participants' eyelids were wide open, a second DCS was associated with less decoupling between the visual network and higher-order cognitive networks that included dorsal/ventral attention and default mode networks. In subcortical structures, eyelid closures were associated with increased connectivity between the striatum and thalamus with the ventral attention network, and greater anticorrelation with the dorsal attention network. When applied to task-based fMRI data, these two DCS predicted interindividual differences in frequency of behavioral lapsing and intraindividual temporal fluctuations in response speed. These findings with participants who underwent a night of total sleep deprivation were replicated in an independent dataset involving partially sleep-deprived participants. Fluctuations in functional connectivity thus appear to be clearly associated with changes in arousal.


Asunto(s)
Nivel de Alerta/fisiología , Conectoma/clasificación , Privación de Sueño/fisiopatología , Sueño/fisiología , Vigilia/fisiología , Atención/fisiología , Mapeo Encefálico , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/fisiología , Párpados/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiología , Vías Nerviosas/fisiología , Tiempo de Reacción , Tálamo/anatomía & histología , Tálamo/fisiología , Adulto Joven
15.
J Neurosci ; 36(8): 2438-48, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26911691

RESUMEN

Structural neuroimaging of humans with typical and atypical sex-chromosome complements has established the marked influence of both Yand X-/Y-chromosome dosage on total brain volume (TBV) and identified potential cortical substrates for the psychiatric phenotypes associated with sex-chromosome aneuploidy (SCA). Here, in a cohort of 354 humans with varying karyotypes (XX, XY, XXX, XXY, XYY, XXYY, XXXXY), we investigate sex and SCA effects on subcortical size and shape; focusing on the striatum, pallidum and thalamus. We find large effect-size differences in the volume and shape of all three structures as a function of sex and SCA. We correct for TBV effects with a novel allometric method harnessing normative scaling rules for subcortical size and shape in humans, which we derive here for the first time. We show that all three subcortical volumes scale sublinearly with TBV among healthy humans, mirroring known relationships between subcortical volume and TBV among species. Traditional TBV correction methods assume linear scaling and can therefore invert or exaggerate sex and SCA effects on subcortical anatomy. Allometric analysis restricts sex-differences to: (1) greater pallidal volume (PV) in males, and (2) relative caudate head expansion and ventral striatum contraction in females. Allometric analysis of SCA reveals that supernumerary X- and Y-chromosomes both cause disproportionate reductions in PV, and coordinated deformations of striatopallidal shape. Our study provides a novel understanding of sex and sex-chromosome dosage effects on subcortical organization, using an allometric approach that can be generalized to other basic and clinical structural neuroimaging settings.


Asunto(s)
Cuerpo Estriado/anatomía & histología , Dosificación de Gen/fisiología , Globo Pálido/anatomía & histología , Caracteres Sexuales , Cromosomas Sexuales/fisiología , Tálamo/anatomía & histología , Adolescente , Adulto , Aneuploidia , Encéfalo/anatomía & histología , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Masculino , Adulto Joven
16.
Usp Fiziol Nauk ; 47(3): 17-29, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-29283228

RESUMEN

Based on the process needs, motivations and emotions, are describing molecular, cellular and systemic mechanisms of goal-direction motivated behavior. Goal-direction behavior is impossible without the orientation in space and forming a cognitive map. This process implements the hippocampus, via the neocortical connections. The hippocampus is linked to the amygdala, which is involved in the implementation of emotional behavior and organizing emotionally intense cognitive map or context of the environment.


Asunto(s)
Amígdala del Cerebelo/fisiología , Cognición/fisiología , Emociones/fisiología , Hipocampo/fisiología , Red Nerviosa/fisiología , Amígdala del Cerebelo/anatomía & histología , Mapeo Encefálico , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/fisiología , Hipocampo/anatomía & histología , Humanos , Motivación/fisiología , Neocórtex/anatomía & histología , Neocórtex/fisiología , Red Nerviosa/anatomía & histología , Plasticidad Neuronal/fisiología , Receptores Dopaminérgicos/fisiología , Receptores de GABA/fisiología , Receptores de Glutamato Metabotrópico/fisiología , Transducción de Señal , Tálamo/anatomía & histología , Tálamo/fisiología
17.
PLoS One ; 10(6): e0129508, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26079870

RESUMEN

In sport events like Olympic Games or World Championships competitive athletes keep pushing the boundaries of human performance. Compared to team sports, high achievements in many athletic disciplines depend solely on the individual's performance. Contrasting previous research looking for expertise-related differences in brain anatomy at the group level, we aim to demonstrate changes in individual top athlete's brain, which would be averaged out in a group analysis. We compared structural magnetic resonance images (MRI) of three professional track-and-field athletes to age-, gender- and education-matched control subjects. To determine brain features specific to these top athletes, we tested for significant deviations in structural grey matter density between each of the three top athletes and a carefully matched control sample. While total brain volumes were comparable between athletes and controls, we show regional grey matter differences in striatum and thalamus. The demonstrated brain anatomy patterns remained stable and were detected after 2 years with Olympic Games in between. We also found differences in the fusiform gyrus in two top long jumpers. We interpret our findings in reward-related areas as correlates of top athletes' persistency to reach top-level skill performance over years.


Asunto(s)
Atletas , Encéfalo/anatomía & histología , Neuroanatomía/métodos , Atletismo/fisiología , Adulto , Rendimiento Atlético/fisiología , Cuerpo Estriado/anatomía & histología , Sustancia Gris/anatomía & histología , Humanos , Imagen por Resonancia Magnética , Masculino , Músculo Esquelético/fisiología , Resistencia Física/fisiología , Esfuerzo Físico/fisiología , Tálamo/anatomía & histología
18.
Neuroscience ; 300: 286-96, 2015 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-26002313

RESUMEN

Impulsive actions and decisions often lead to undesirable outcomes. Lesion and neuroimaging studies have revealed that the orbital frontal cortex (OFC) and dorsal striatum (dSTR) play key roles in inhibitory control. It has been proposed that greater OFC input into the dSTR reflects enhanced top-down cognitive control and less impulsive responding. We previously reported a sex difference in inhibitory control, such that female rats make fewer impulsive errors than do male rats. The goal of the present study was to investigate differences in the OFC and dSTR of young adult male and female rats. In Experiment 1, we measured levels of two myelin-associated proteins, myelin basic protein (MBP) and myelin proteolipid protein (PLP), in the OFC and dSTR. Western blot data revealed that females had significantly higher levels of both MBP and PLP in the OFC but similar levels in the dSTR as compared to males. In Experiment 2, we infused the anterograde tracer, biotinylated dextran amine (BDA), into the OFC and measured the density of BDA in the dSTR. BDA was visualized using histochemistry followed by light microscopy imaging and densitometry analysis. Density of BDA in the dSTR was significantly greater in females as compared to males indicating that the projections from the OFC to dSTR may be greater in females as compared to males. Our results suggest a potential neuroanatomical sex difference that may contribute to the reported differences in inhibitory control levels of male and female rats.


Asunto(s)
Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/fisiología , Lóbulo Frontal/anatomía & histología , Lóbulo Frontal/fisiología , Proteína Básica de Mielina/metabolismo , Caracteres Sexuales , Animales , Biotina/análogos & derivados , Western Blotting , Dextranos , Función Ejecutiva/fisiología , Femenino , Inhibición Psicológica , Masculino , Microscopía , Proteína Proteolipídica de la Mielina/metabolismo , Técnicas de Trazados de Vías Neuroanatómicas , Trazadores del Tracto Neuronal , Ratas Long-Evans
19.
Neuroscience ; 274: 409-18, 2014 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-24909897

RESUMEN

Within the first two postnatal weeks, corticostriatal axons from the primary somatosensory cortex (S1) form topographic projections that organize into characteristic bands of axon terminals in the dorsolateral striatum. Molecules regulating the development of these topographically organized projections are currently unknown. Thus, the present study investigated whether EphA receptor tyrosine kinases, which regulate axonal guidance in the visual system via axon repulsion, could participate in the formation of corticostriatal connections during development. Prior studies indicate that EphA7-expressing striatal neurons are organized into banded compartments resembling the matrisome innervation pattern formed by cortical afferents from the S1 cortex and that ephrin-A5, a known EphA7 ligand, is expressed in a medial (high) to lateral (low) gradient in S1. Thus, we hypothesized that the organization of EphA7-expressing striatal neurons in banded domains provides a repulsive barrier preventing corticostriatal axons containing EphA7-ligands from innervating inappropriate regions of the striatum. To evaluate this, we injected the anterograde tracer, biotinylated dextran amine (BDA), into two locations in medial areas of S1 (the anterior and posterior whisker fields), which are reported to express high levels of ephrin-A5 during development. Injections were made in mouse pups on postnatal day 9 (P9) and the animals were processed for immunohistochemistry on P12. Our data demonstrate that projections from both the forelimb/anterior whisker field and the posterior whisker field avoid EphA7-expressing neurons and terminate in a banded pattern in regions with very low EphA7-expression. We also determined that corticothalamic projections from medial S1 also exhibit a restricted distribution in the thalamus and avoid neurons expressing EphA7. Thus, our results support the hypothesis that the anatomical organization of striatal and thalamic neurons expressing EphA7 receptors restricts the topographic distribution of cortical afferents from medial regions of S1 which express high levels of ephrin-A5.


Asunto(s)
Cuerpo Estriado/anatomía & histología , Neuronas/citología , Receptor EphA7/metabolismo , Corteza Somatosensorial/anatomía & histología , Tálamo/anatomía & histología , Animales , Biotina/análogos & derivados , Cuerpo Estriado/metabolismo , Dextranos , Complejo IV de Transporte de Electrones/metabolismo , Inmunohistoquímica , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Vías Nerviosas/anatomía & histología , Vías Nerviosas/metabolismo , Técnicas de Trazados de Vías Neuroanatómicas , Neuronas/metabolismo , Tálamo/metabolismo , Vibrisas
20.
Neurosci Biobehav Rev ; 37(4): 681-96, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23415703

RESUMEN

One fundamental question concerning brain reward mechanisms is to determine how reward-related activity is influenced by the nature of rewards. Here, we review the neuroimaging literature and explicitly assess to what extent the representations of primary and secondary rewards overlap in the human brain. To achieve this goal, we performed an activation likelihood estimation (ALE) meta-analysis of 87 studies (1452 subjects) comparing the brain responses to monetary, erotic and food reward outcomes. Those three rewards robustly engaged a common brain network including the ventromedial prefrontal cortex, ventral striatum, amygdala, anterior insula and mediodorsal thalamus, although with some variations in the intensity and location of peak activity. Money-specific responses were further observed in the most anterior portion of the orbitofrontal cortex, supporting the idea that abstract secondary rewards are represented in evolutionary more recent brain regions. In contrast, food and erotic (i.e. primary) rewards were more strongly represented in the anterior insula, while erotic stimuli elicited particularly robust responses in the amygdala. Together, these results indicate that the computation of experienced reward value does not only recruit a core "reward system" but also reward type-dependent brain structures.


Asunto(s)
Encéfalo/fisiología , Neuroimagen , Recompensa , Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/fisiología , Animales , Encéfalo/anatomía & histología , Corteza Cerebral/anatomía & histología , Corteza Cerebral/fisiología , Cuerpo Estriado/anatomía & histología , Cuerpo Estriado/fisiología , Humanos , Hipotálamo/fisiología , Corteza Prefrontal/anatomía & histología , Corteza Prefrontal/fisiología , Tálamo/fisiología , Corteza Visual/fisiología
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