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1.
Nature ; 604(7906): 525-533, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35388223

RESUMEN

Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes.


Asunto(s)
Encéfalo , Longevidad , Estatura , Encéfalo/anatomía & histología , Humanos , Imagen por Resonancia Magnética/métodos , Neuroimagen
2.
Hum Brain Mapp ; 44(17): 5729-5748, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37787573

RESUMEN

Despite the known benefits of data-driven approaches, the lack of approaches for identifying functional neuroimaging patterns that capture both individual variations and inter-subject correspondence limits the clinical utility of rsfMRI and its application to single-subject analyses. Here, using rsfMRI data from over 100k individuals across private and public datasets, we identify replicable multi-spatial-scale canonical intrinsic connectivity network (ICN) templates via the use of multi-model-order independent component analysis (ICA). We also study the feasibility of estimating subject-specific ICNs via spatially constrained ICA. The results show that the subject-level ICN estimations vary as a function of the ICN itself, the data length, and the spatial resolution. In general, large-scale ICNs require less data to achieve specific levels of (within- and between-subject) spatial similarity with their templates. Importantly, increasing data length can reduce an ICN's subject-level specificity, suggesting longer scans may not always be desirable. We also find a positive linear relationship between data length and spatial smoothness (possibly due to averaging over intrinsic dynamics), suggesting studies examining optimized data length should consider spatial smoothness. Finally, consistency in spatial similarity between ICNs estimated using the full data and subsets across different data lengths suggests lower within-subject spatial similarity in shorter data is not wholly defined by lower reliability in ICN estimates, but may be an indication of meaningful brain dynamics which average out as data length increases.


Asunto(s)
Mapeo Encefálico , Imagen por Resonancia Magnética , Humanos , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Reproducibilidad de los Resultados , Red Nerviosa/diagnóstico por imagen , Encéfalo/diagnóstico por imagen
4.
Neuroimage ; 251: 119013, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35189361

RESUMEN

Resting-state functional magnetic resonance imaging is currently the mainstay of functional neuroimaging and has allowed researchers to identify intrinsic connectivity networks (aka functional networks) at different spatial scales. However, little is known about the temporal profiles of these networks and whether it is best to model them as continuous phenomena in both space and time or, rather, as a set of temporally discrete events. Both categories have been supported by series of studies with promising findings. However, a critical question is whether focusing only on time points presumed to contain isolated neural events and disregarding the rest of the data is missing important information, potentially leading to misleading conclusions. In this work, we argue that brain networks identified within the spontaneous blood oxygenation level-dependent (BOLD) signal are not limited to temporally sparse burst moments and that these event present time points (EPTs) contain valuable but incomplete information about the underlying functional patterns. We focus on the default mode and show evidence that is consistent with its continuous presence in the BOLD signal, including during the event absent time points (EATs), i.e., time points that exhibit minimum activity and are the least likely to contain an event. Moreover, our findings suggest that EPTs may not contain all the available information about their corresponding networks. We observe distinct default mode connectivity patterns obtained from all time points (AllTPs), EPTs, and EATs. We show evidence of robust relationships with schizophrenia symptoms that are both common and unique to each of the sets of time points (AllTPs, EPTs, EATs), likely related to transient patterns of connectivity. Together, these findings indicate the importance of leveraging the full temporal data in functional studies, including those using event-detection approaches.


Asunto(s)
Mapeo Encefálico , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética/métodos , Red Nerviosa/diagnóstico por imagen
5.
Neuroimage ; 225: 117438, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33039623

RESUMEN

Brain development has largely been studied through unimodal analysis of neuroimaging data, providing independent results for structural and functional data. However, structure clearly impacts function and vice versa, pointing to the need for performing multimodal data collection and analysis to improve our understanding of brain development, and to further inform models of typical and atypical brain development across the lifespan. Ultimately, such models should also incorporate genetic and epigenetic mechanisms underlying brain structure and function, although currently this area is poorly specified. To this end, we are reporting here a multi-site, multi-modal dataset that captures cognitive function, brain structure and function, and genetic and epigenetic measures to better quantify the factors that influence brain development in children originally aged 9-14 years. Data collection for the Developmental Chronnecto-Genomics (Dev-CoG) study (http://devcog.mrn.org/) includes cognitive, emotional, and social performance scales, structural and functional MRI, diffusion MRI, magnetoencephalography (MEG), and saliva collection for DNA analysis of single nucleotide polymorphisms (SNPs) and DNA methylation patterns. Across two sites (The Mind Research Network and the University of Nebraska Medical Center), data from over 200 participants were collected and these children were re-tested annually for at least 3 years. The data collection protocol, sample demographics, and data quality measures for the dataset are presented here. The sample will be made freely available through the collaborative informatics and neuroimaging suite (COINS) database at the conclusion of the study.


Asunto(s)
Encéfalo/diagnóstico por imagen , Desarrollo Infantil , Cognición , Adolescente , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Niño , Conectoma , Metilación de ADN , Imagen de Difusión por Resonancia Magnética , Femenino , Neuroimagen Funcional , Genómica , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Neuroimagen , Polimorfismo de Nucleótido Simple , Factores de Tiempo
6.
Neuroimage ; 190: 191-204, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29883735

RESUMEN

Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with social communication deficits and restricted/repetitive behaviors and is characterized by large-scale atypical subcortical-cortical connectivity, including impaired resting-state functional connectivity between thalamic and sensory regions. Previous studies have typically focused on the abnormal static connectivity in ASD and overlooked potential valuable dynamic patterns in brain connectivity. However, resting-state brain connectivity is indeed highly dynamic, and abnormalities in dynamic brain connectivity have been widely identified in psychiatric disorders. In this study, we investigated the dynamic functional network connectivity (dFNC) between 51 intrinsic connectivity networks in 170 individuals with ASD and 195 age-matched typically developing (TD) controls using independent component analysis and a sliding window approach. A hard clustering state analysis and a fuzzy meta-state analysis were conducted respectively, for the exploration of local and global aberrant dynamic connectivity patterns in ASD. We examined the group difference in dFNC between thalamic and sensory networks in each functional state and group differences in four high-dimensional dynamic measures. The results showed that compared with TD controls, individuals with ASD show an increase in transient connectivity between hypothalamus/subthalamus and some sensory networks (right postcentral gyrus, bi paracentral lobule, and lingual gyrus) in certain functional states, and diminished global meta-state dynamics of the whole-brain functional network. In addition, these atypical dynamic patterns are significantly associated with autistic symptoms indexed by the Autism Diagnostic Observation Schedule. These converging results support and extend previous observations regarding hyperconnectivity between thalamic and sensory regions and stable whole-brain functional configuration in ASD. Dynamic brain connectivity may serve as a potential biomarker of ASD and further investigation of these dynamic patterns might help to advance our understanding of behavioral differences in this complex neurodevelopmental disorder.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Encéfalo/fisiopatología , Conectoma/métodos , Red Nerviosa/fisiopatología , Adolescente , Adulto , Trastorno del Espectro Autista/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Niño , Femenino , Humanos , Hipotálamo/diagnóstico por imagen , Hipotálamo/fisiopatología , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Subtálamo/diagnóstico por imagen , Subtálamo/fisiopatología , Tálamo/diagnóstico por imagen , Tálamo/fisiopatología , Adulto Joven
7.
Mol Psychiatry ; 23(5): 1261-1269, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29038599

RESUMEN

The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.


Asunto(s)
Esquizofrenia/diagnóstico por imagen , Esquizofrenia/fisiopatología , Sustancia Blanca/ultraestructura , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/fisiopatología , Estudios de Cohortes , Cuerpo Calloso/fisiopatología , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Sustancia Blanca/fisiopatología , Adulto Joven
8.
Neuroimage ; 180(Pt B): 619-631, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28939432

RESUMEN

The human brain is a highly dynamic system with non-stationary neural activity and rapidly-changing neural interaction. Resting-state dynamic functional connectivity (dFC) has been widely studied during recent years, and the emerging aberrant dFC patterns have been identified as important features of many mental disorders such as schizophrenia (SZ). However, only focusing on the time-varying patterns in FC is not enough, since the local neural activity itself (in contrast to the inter-connectivity) is also found to be highly fluctuating from research using high-temporal-resolution imaging techniques. Exploring the time-varying patterns in brain activity and their relationships with time-varying brain connectivity is important for advancing our understanding of the co-evolutionary property of brain network and the underlying mechanism of brain dynamics. In this study, we introduced a framework for characterizing time-varying brain activity and exploring its associations with time-varying brain connectivity, and applied this framework to a resting-state fMRI dataset including 151 SZ patients and 163 age- and gender matched healthy controls (HCs). In this framework, 48 brain regions were first identified as intrinsic connectivity networks (ICNs) using group independent component analysis (GICA). A sliding window approach was then adopted for the estimation of dynamic amplitude of low-frequency fluctuation (dALFF) and dFC, which were used to measure time-varying brain activity and time-varying brain connectivity respectively. The dALFF was further clustered into six reoccurring states by the k-means clustering method and the group difference in occurrences of dALFF states was explored. Lastly, correlation coefficients between dALFF and dFC were calculated and the group difference in these dALFF-dFC correlations was explored. Our results suggested that 1) ALFF of brain regions was highly fluctuating during the resting-state and such dynamic patterns are altered in SZ, 2) dALFF and dFC were correlated in time and their correlations are altered in SZ. The overall results support and expand prior work on abnormalities of brain activity, static FC (sFC) and dFC in SZ, and provide new evidence on aberrant time-varying brain activity and its associations with brain connectivity in SZ, which might underscore the disrupted brain cognitive functions in this mental disorder.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Red Nerviosa/fisiología , Esquizofrenia/fisiopatología , Adulto , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiología , Esquizofrenia/diagnóstico por imagen
9.
Psychol Med ; 48(15): 2492-2499, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29444726

RESUMEN

BACKGROUND: Schizophrenia (SZ) is a severe neuropsychiatric disorder associated with disrupted connectivity within the thalamic-cortico-cerebellar network. Resting-state functional connectivity studies have reported thalamic hypoconnectivity with the cerebellum and prefrontal cortex as well as thalamic hyperconnectivity with sensory cortical regions in SZ patients compared with healthy comparison participants (HCs). However, fundamental questions remain regarding the clinical significance of these connectivity abnormalities. METHOD: Resting state seed-based functional connectivity was used to investigate thalamus to whole brain connectivity using multi-site data including 183 SZ patients and 178 matched HCs. Statistical significance was based on a voxel-level FWE-corrected height threshold of p < 0.001. The relationships between positive and negative symptoms of SZ and regions of the brain demonstrating group differences in thalamic connectivity were examined. RESULTS: HC and SZ participants both demonstrated widespread positive connectivity between the thalamus and cortical regions. Compared with HCs, SZ patients had reduced thalamic connectivity with bilateral cerebellum and anterior cingulate cortex. In contrast, SZ patients had greater thalamic connectivity with multiple sensory-motor regions, including bilateral pre- and post-central gyrus, middle/inferior occipital gyrus, and middle/superior temporal gyrus. Thalamus to middle temporal gyrus connectivity was positively correlated with hallucinations and delusions, while thalamus to cerebellar connectivity was negatively correlated with delusions and bizarre behavior. CONCLUSIONS: Thalamic hyperconnectivity with sensory regions and hypoconnectivity with cerebellar regions in combination with their relationship to clinical features of SZ suggest that thalamic dysconnectivity may be a core neurobiological feature of SZ that underpins positive symptoms.


Asunto(s)
Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Conectoma/métodos , Red Nerviosa/fisiopatología , Esquizofrenia/fisiopatología , Tálamo/fisiopatología , Adulto , Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Tálamo/diagnóstico por imagen
10.
Acta Psychiatr Scand ; 138(5): 472-482, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30084192

RESUMEN

OBJECTIVE: This study determined the clinical utility of an fMRI classification algorithm predicting medication-class of response in patients with challenging mood diagnoses. METHODS: Ninety-nine 16-27-year-olds underwent resting state fMRI scans in three groups-BD, MDD and healthy controls. A predictive algorithm was trained and cross-validated on the known-diagnosis patients using maximally spatially independent components (ICs), constructing a similarity matrix among subjects, partitioning the matrix in kernel space and optimizing support vector machine classifiers and IC combinations. This classifier was also applied to each of 12 new individual patients with unclear mood disorder diagnoses. RESULTS: Classification within the known-diagnosis group was approximately 92.4% accurate. The five maximally contributory ICs were identified. Applied to the complicated patients, the algorithm diagnosis was consistent with optimal medication-class of response to sustained recovery in 11 of 12 cases (i.e., almost 92% accuracy). CONCLUSION: This classification algorithm performed well for the know-diagnosis but also predicted medication-class of response in difficult-to-diagnose patients. Further research can enhance this approach and extend these findings to be more clinically accessible.


Asunto(s)
Trastorno Bipolar/diagnóstico por imagen , Conectoma/métodos , Trastorno Depresivo Mayor/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Máquina de Vectores de Soporte , Adolescente , Adulto , Trastorno Bipolar/clasificación , Trastorno Depresivo Mayor/clasificación , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Adulto Joven
11.
Brain Topogr ; 31(1): 101-116, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28229308

RESUMEN

The human brain operates by dynamically modulating different neural populations to enable goal directed behavior. The synchrony or lack thereof between different brain regions is thought to correspond to observed functional connectivity dynamics in resting state brain imaging data. In a large sample of healthy human adult subjects and utilizing a sliding windowed correlation method on functional imaging data, earlier we demonstrated the presence of seven distinct functional connectivity states/patterns between different brain networks that reliably occur across time and subjects. Whether these connectivity states correspond to meaningful electrophysiological signatures was not clear. In this study, using a dataset with concurrent EEG and resting state functional imaging data acquired during eyes open and eyes closed states, we demonstrate the replicability of previous findings in an independent sample, and identify EEG spectral signatures associated with these functional network connectivity changes. Eyes open and eyes closed conditions show common and different connectivity patterns that are associated with distinct EEG spectral signatures. Certain connectivity states are more prevalent in the eyes open case and some occur only in eyes closed state. Both conditions exhibit a state of increased thalamocortical anticorrelation associated with reduced EEG spectral alpha power and increased delta and theta power possibly reflecting drowsiness. This state occurs more frequently in the eyes closed state. In summary, we find a link between dynamic connectivity in fMRI data and concurrently collected EEG data, including a large effect of vigilance on functional connectivity. As demonstrated with EEG and fMRI, the stationarity of connectivity cannot be assumed, even for relatively short periods.


Asunto(s)
Electroencefalografía/métodos , Red Nerviosa/anatomía & histología , Red Nerviosa/fisiología , Adulto , Nivel de Alerta/fisiología , Mapeo Encefálico , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiología , Ritmo Delta/fisiología , Fenómenos Electrofisiológicos , Ojo , Femenino , Voluntarios Sanos , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Tálamo/diagnóstico por imagen , Tálamo/fisiología , Ritmo Teta/fisiología , Adulto Joven
12.
Mol Psychiatry ; 21(4): 547-53, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26033243

RESUMEN

The profile of brain structural abnormalities in schizophrenia is still not fully understood, despite decades of research using brain scans. To validate a prospective meta-analysis approach to analyzing multicenter neuroimaging data, we analyzed brain MRI scans from 2028 schizophrenia patients and 2540 healthy controls, assessed with standardized methods at 15 centers worldwide. We identified subcortical brain volumes that differentiated patients from controls, and ranked them according to their effect sizes. Compared with healthy controls, patients with schizophrenia had smaller hippocampus (Cohen's d=-0.46), amygdala (d=-0.31), thalamus (d=-0.31), accumbens (d=-0.25) and intracranial volumes (d=-0.12), as well as larger pallidum (d=0.21) and lateral ventricle volumes (d=0.37). Putamen and pallidum volume augmentations were positively associated with duration of illness and hippocampal deficits scaled with the proportion of unmedicated patients. Worldwide cooperative analyses of brain imaging data support a profile of subcortical abnormalities in schizophrenia, which is consistent with that based on traditional meta-analytic approaches. This first ENIGMA Schizophrenia Working Group study validates that collaborative data analyses can readily be used across brain phenotypes and disorders and encourages analysis and data sharing efforts to further our understanding of severe mental illness.


Asunto(s)
Encéfalo/patología , Esquizofrenia/patología , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Estudios de Casos y Controles , Femenino , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Estudios Prospectivos , Esquizofrenia/genética
13.
Neuroimage ; 104: 310-25, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25241084

RESUMEN

Brain lateralization is a widely studied topic, however there has been little work focused on lateralization of intrinsic networks (regions showing similar patterns of covariation among voxels) in the resting brain. In this study, we evaluate resting state network lateralization in an age and gender-balanced functional magnetic resonance imaging (fMRI) dataset comprising over 600 healthy subjects ranging in age from 12 to 71. After establishing sample-wide network lateralization properties, we continue with an investigation of age and gender effects on network lateralization. All data was gathered on the same scanner and preprocessed using an automated pipeline (Scott et al., 2011). Networks were extracted via group independent component analysis (gICA) (Calhoun et al., 2001). Twenty-eight resting state networks discussed in previous (Allen et al., 2011) work were re-analyzed with a focus on lateralization. We calculated homotopic voxelwise measures of laterality in addition to a global lateralization measure, called the laterality cofactor, for each network. As expected, many of the intrinsic brain networks were lateralized. For example, the visual network was strongly right lateralized, auditory network and default mode networks were mostly left lateralized. Attentional and frontal networks included nodes that were left lateralized and other nodes that were right lateralized. Age was strongly related to lateralization in multiple regions including sensorimotor network regions precentral gyrus, postcentral gyrus and supramarginal gyrus; and visual network regions lingual gyrus; attentional network regions inferior parietal lobule, superior parietal lobule and middle temporal gyrus; and frontal network regions including the inferior frontal gyrus. Gender showed significant effects mainly in two regions, including visual and frontal networks. For example, the inferior frontal gyrus was more right lateralized in males. Significant effects of age were found in sensorimotor and visual networks on the global measure. In summary, we report a large-sample of lateralization study that finds intrinsic functional brain networks to be highly lateralized, with regions that are strongly related to gender and age locally, and with age a strong factor in lateralization, and gender exhibiting a trend-level effect on global measures of laterality.


Asunto(s)
Encéfalo/fisiología , Lateralidad Funcional/fisiología , Red Nerviosa/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Mapeo Encefálico , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto Joven
14.
Acta Psychiatr Scand ; 132(1): 29-38, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25572430

RESUMEN

OBJECTIVE: Post-traumatic stress disorder (PTSD) is considered a multidimensional disorder, with distinct symptom clusters including re-experiencing, avoidance/numbing, hyperarousal, and most recently depersonalization/derealization. However, the extent of differing intrinsic network connectivity underlying these symptoms has not been fully investigated. We therefore investigated the degree of association between resting connectivity of the salience (SN), default mode (DMN), and central executive (CEN) networks and PTSD symptom severity. METHOD: Using resting-state functional MRI data from PTSD participants (n = 21), we conducted multivariate analyses to test whether connectivity of extracted independent components varied as a function of re-experiencing, avoidance/numbing, hyperarousal, and depersonalization/derealization. RESULTS: Hyperarousal symptoms were associated with reduced connectivity of posterior insula/superior temporal gyrus within SN [peak Montréal Neurological Institute (MNI): -44, -8, 0, t = -4.2512, k = 40]. Depersonalization/derealization severity was associated with decreased connectivity of perigenual anterior cingulate/ventromedial prefrontal cortex within ventral anterior DMN (peak MNI: 8, 40, -4; t = -3.8501; k = 15) and altered synchrony between two DMN components and between DMN and CEN. CONCLUSION: Our results are consistent with prior research showing intrinsic network disruptions in PTSD and imply heterogeneous connectivity patterns underlying PTSD symptom dimensions. These findings suggest possible biomarkers for PTSD and its dissociative subtype.


Asunto(s)
Encéfalo/fisiopatología , Vías Nerviosas/fisiopatología , Trastornos por Estrés Postraumático/fisiopatología , Mapeo Encefálico , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Lóbulo Parietal/fisiopatología , Corteza Prefrontal/fisiopatología
15.
Neuroimage ; 84: 169-80, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23994454

RESUMEN

We characterize the development of intrinsic connectivity networks (ICNs) from 4 to 9months of age with resting state magnetic resonance imaging performed on sleeping infants without sedative medication. Data is analyzed with independent component analysis (ICA). Using both low (30 components) and high (100 components) ICA model order decompositions, we find that the functional network connectivity (FNC) map is largely similar at both 4 and 9months. However at 9months the connectivity strength decreases within local networks and increases between more distant networks. The connectivity within the default-mode network, which contains both local and more distant nodes, also increases in strength with age. The low frequency power spectrum increases with age only in the posterior cingulate cortex and posterior default mode network. These findings are consistent with a general developmental pattern of increasing longer distance functional connectivity over the first year of life and raise questions regarding the developmental importance of the posterior cingulate at this age.


Asunto(s)
Envejecimiento/fisiología , Encéfalo/fisiología , Conectoma/métodos , Interpretación de Imagen Asistida por Computador/métodos , Red Nerviosa/fisiología , Plasticidad Neuronal/fisiología , Sueño/fisiología , Niño , Preescolar , Femenino , Humanos , Estudios Longitudinales , Masculino , Vías Nerviosas/fisiología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Psychol Med ; 44(6): 1257-65, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23866983

RESUMEN

BACKGROUND: Relatively lower executive functioning is characteristic of individuals with schizophrenia. As low socio-economic status (SES) early in life (i.e. parent SES) has been linked with lower executive skills in healthy children, we hypothesized that parental SES (pSES) would be more strongly related to executive functioning in individuals with schizophrenia than in controls and have a greater impact on prefrontal cortical morphology. METHOD: Healthy controls (n = 125) and individuals with schizophrenia (n = 102) completed tests assessing executive functioning and intelligence. The groups were matched on pSES, which was evaluated with the Hollingshead-Redlich scale. A principal components analysis (PCA) was conducted on 10 variables from six executive tests, yielding three specific components (fluency, planning and response inhibition). Voxel-based morphometry (VBM) was used to evaluate effects of pSES on gray matter (GM) concentration. RESULTS: Lower pSES was associated with lower scores across the three executive functioning components, and a significant group by pSES interaction was observed such that low pSES, in particular, affected individuals with schizophrenia. These effects remained significant when intellectual ability, education and self-SES (sSES) were added as covariates. VBM revealed that lower pSES was associated with reduced GM volume in several anterior brain regions, especially the superior frontal gyrus, in patients but not in controls. CONCLUSIONS: These findings suggest that individuals with schizophrenia may be particularly vulnerable to the adverse impact of low pSES, in terms of both lower executive skills and reduced anterior GM volumes.


Asunto(s)
Función Ejecutiva/fisiología , Corteza Prefrontal/patología , Esquizofrenia/fisiopatología , Clase Social , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Padres , Esquizofrenia/patología
18.
Mol Psychiatry ; 18(11): 1199-204, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23337947

RESUMEN

N-methyl-D-aspartate glutamate receptor (NMDA-R) antagonists produce schizophrenia-like positive and negative symptoms in healthy human subjects. Preclinical research suggests that NMDA-R antagonists interfere with the function of gamma-aminobutyric acid (GABA) neurons and alter the brain oscillations. These changes have been hypothesized to contribute to psychosis. In this investigation, we evaluated the hypothesis that the NMDA-R antagonist ketamine produces alterations in cortical functional connectivity during rest that are related to symptoms. We administered ketamine to a primary sample of 22 subjects and to an additional, partially overlapping, sample of 12 subjects. Symptoms before and after the experimental session were rated with the Positive and Negative Syndrome Scale (PANSS). In the primary sample, functional connectivity was measured via functional magnetic resonance imaging almost immediately after infusion began. In the additional sample, this assessment was repeated after 45 min of continuous ketamine infusion. Global, enhanced functional connectivity was observed at both timepoints, and this hyperconnectivity was related to symptoms in a region-specific manner. This study supports the hypothesis that pathological increases in resting brain functional connectivity contribute to the emergence of positive and negative symptoms associated with schizophrenia.


Asunto(s)
Corteza Cerebral/fisiopatología , Antagonistas de Aminoácidos Excitadores/farmacología , Ketamina/farmacología , Esquizofrenia/fisiopatología , Adulto , Mapeo Encefálico , Corteza Cerebral/efectos de los fármacos , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Voluntarios Sanos/psicología , Humanos , Ketamina/sangre , Masculino , Persona de Mediana Edad , Esquizofrenia/inducido químicamente , Esquizofrenia/diagnóstico
19.
Acta Psychiatr Scand ; 130(2): 123-36, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24266644

RESUMEN

OBJECTIVE: Electroencephalographic (EEG) neurofeedback training has been shown to produce plastic modulations in salience network and default mode network functional connectivity in healthy individuals. In this study, we investigated whether a single session of neurofeedback training aimed at the voluntary reduction of alpha rhythm (8-12 Hz) amplitude would be related to differences in EEG network oscillations, functional MRI (fMRI) connectivity, and subjective measures of state anxiety and arousal in a group of individuals with post-traumatic stress disorder (PTSD). METHOD: Twenty-one individuals with PTSD related to childhood abuse underwent 30 min of EEG neurofeedback training preceded and followed by a resting-state fMRI scan. RESULTS: Alpha desynchronizing neurofeedback was associated with decreased alpha amplitude during training, followed by a significant increase ('rebound') in resting-state alpha synchronization. This rebound was linked to increased calmness, greater salience network connectivity with the right insula, and enhanced default mode network connectivity with bilateral posterior cingulate, right middle frontal gyrus, and left medial prefrontal cortex. CONCLUSION: Our study represents a first step in elucidating the potential neurobehavioural mechanisms mediating the effects of neurofeedback treatment on regulatory systems in PTSD. Moreover, it documents for the first time a spontaneous EEG 'rebound' after neurofeedback, pointing to homeostatic/compensatory mechanisms operating in the brain.


Asunto(s)
Ritmo alfa/fisiología , Corteza Cerebral/fisiopatología , Red Nerviosa/fisiopatología , Neurorretroalimentación/fisiología , Trastornos por Estrés Postraumático/fisiopatología , Adulto , Ansiedad/fisiopatología , Nivel de Alerta/fisiología , Conectoma , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neurorretroalimentación/instrumentación , Neurorretroalimentación/métodos , Plasticidad Neuronal/fisiología , Trastornos por Estrés Postraumático/terapia , Resultado del Tratamiento
20.
Int J Clin Health Psychol ; 24(2): 100458, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38623146

RESUMEN

Background/Objective. Enlarged lateral ventricle (LV) volume and decreased volume in the corpus callosum (CC) are hallmarks of schizophrenia (SZ). We previously showed an inverse correlation between LV and CC volumes in SZ, with global functioning decreasing with increased LV volume. This study investigates the relationship between LV volume, CC abnormalities, and the microRNA MIR137 and its regulated genes in SZ, because of MIR137's essential role in neurodevelopment. Methods. Participants were 1224 SZ probands and 1466 unaffected controls from the GENUS Consortium. Brain MRI scans, genotype, and clinical data were harmonized across cohorts and employed in the analyses. Results. Increased LV volumes and decreased CC central, mid-anterior, and mid-posterior volumes were observed in SZ probands. The MIR137-regulated ephrin pathway was significantly associated with CC:LV ratio, explaining a significant proportion (3.42 %) of CC:LV variance, and more than for LV and CC separately. Other pathways explained variance in either CC or LV, but not both. CC:LV ratio was also positively correlated with Global Assessment of Functioning, supporting previous subsample findings. SNP-based heritability estimates were higher for CC central:LV ratio (0.79) compared to CC or LV separately. Discussion. Our results indicate that the CC:LV ratio is highly heritable, influenced in part by variation in the MIR137-regulated ephrin pathway. Findings suggest that the CC:LV ratio may be a risk indicator in SZ that correlates with global functioning.

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