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independent component analysis fMRI

Ville Raatikainen, Niko Huotari, Vesa Korhonen, Aleksi Rasila, Janne Kananen, Lauri Raitamaa, Tuija Keinänen, Jussi Kantola, Osmo Tervonen, Vesa Kiviniemi
This study investigated lag structure in the resting-state fMRI by applying a novel independent component (ICA) method to magnetic resonance encephalography (MREG) data. Briefly, the spatial ICA (sICA) was used for defining the frontal and back nodes of the default mode network (DMN), and the temporal ICA (tICA), which is enabled by the high temporal resolution of MREG (TR=100ms), was used to separate both neuronal and physiological components of these two spatial map regions. Subsequently, lag structure was investigated between the frontal (DMNvmpf) and posterior (DMNpcc) DMN nodes using both conventional method with all-time points and a sliding-window approach...
January 11, 2017: NeuroImage
Aldo Córdova-Palomera, Tobias Kaufmann, Karin Persson, Dag Alnæs, Nhat Trung Doan, Torgeir Moberget, Martina Jonette Lund, Maria Lage Barca, Andreas Engvig, Anne Brækhus, Knut Engedal, Ole A Andreassen, Geir Selbæk, Lars T Westlye
As findings on the neuropathological and behavioral components of Alzheimer's disease (AD) continue to accrue, converging evidence suggests that macroscale brain functional disruptions may mediate their association. Recent developments on theoretical neuroscience indicate that instantaneous patterns of brain connectivity and metastability may be a key mechanism in neural communication underlying cognitive performance. However, the potential significance of these patterns across the AD spectrum remains virtually unexplored...
January 11, 2017: Scientific Reports
J Cui, O Tymofiyeva, R Desikan, T Flynn, H Kim, D Gano, C P Hess, D M Ferriero, A J Barkovich, D Xu
BACKGROUND AND PURPOSE: Diffusion and fMRI has been providing insights to brain development in addition to anatomic imaging. This study aimed to evaluate the microstructure of white matter tracts underlying the default mode network in premature infants by using resting-state functional MR imaging in conjunction with diffusion tensor imaging-based tractography. MATERIALS AND METHODS: A cohort of 44 preterm infants underwent structural T1-weighted imaging, resting-state fMRI, and DTI at 3T, including 21 infants with brain injuries and 23 infants with normal-appearing structural imaging as controls...
November 10, 2016: AJNR. American Journal of Neuroradiology
E H Middlebrooks, C J Frost, I S Tuna, I M Schmalfuss, M Rahman, A Old Crow
BACKGROUND AND PURPOSE: Although it is a potentially powerful presurgical tool, fMRI can be fraught with artifacts, leading to interpretive errors, many of which are not fully accounted for in routinely applied correction methods. The purpose of this investigation was to evaluate the effects of data denoising by independent component analysis in patients undergoing preoperative evaluation for glioma resection compared with more routinely applied correction methods such as realignment or motion scrubbing...
November 10, 2016: AJNR. American Journal of Neuroradiology
Vinod Jangir Kumar, Erik van Oort, Klaus Scheffler, Christian F Beckmann, Wolfgang Grodd
In the present work, we used resting state-fMRI to investigate the functional anatomy of the thalamus at rest by applying an Independent Component Analysis to delineate thalamic substructures into stable and reproducible parcels for the left and right thalamus. We determined 15 functionally distinct thalamic parcels, which differed in laterality and size but exhibited a correspondence with 18 cytoarchitectonally defined nuclei. We characterized their structural connectivity in determining DWI based cortical fiber pathways and found selected projections to different cortical areas...
December 29, 2016: NeuroImage
Xin Hao, Yi Huang, Xueting Li, Yiying Song, Xiangzhen Kong, Xu Wang, Zetian Yang, Zonglei Zhen, Jia Liu
INTRODUCTION: Navigation is a fundamental and multidimensional cognitive function that individuals rely on to move around the environment. In this study, we investigated the neural basis of human spatial navigation ability. METHODS: A large cohort of participants (N > 200) was examined on their navigation ability behaviorally and structural and functional magnetic resonance imaging (MRI) were then used to explore the corresponding neural basis of spatial navigation...
December 2016: Brain and Behavior
Mengxia Gao, Delong Zhang, Zengjian Wang, Bishan Liang, Yuxuan Cai, Zhenni Gao, Junchao Li, Song Chang, Bingqing Jiao, Ruiwang Huang, Ming Liu
Neuroimaging studies have highlighted that intrinsic brain activity is modified to implement task demands. However, the relation between mental rotation and intrinsic brain activity remains unclear. To answer this question, we collected functional MRI (fMRI) data from 30 healthy participants in two mental rotation task periods (1st-task state, 2nd-task state) and two rest periods before (pre-task resting state) and after the task (post-task resting state) respectively. By combining the spatial independent component analysis (ICA) and voxel-wise functional connectivity strength (FCS), we identified FCS maps of 10 brain resting state networks (RSNs) within six different bands (i...
December 20, 2016: Behavioural Brain Research
Leonardo Cerliani, Rajat M Thomas, Domenico Aquino, Valeria Contarino, Alberto Bizzi
The spatial pattern of task-related brain activity in fMRI studies might be expected to change according to several variables such as handedness and age. However this spatial heterogeneity might also be due to other unmodeled sources of inter-subject variability. Since group-level results reflect patterns of task-evoked brain activity common to most of the subjects in the sample, they could conceal the presence of subgroups recruiting other brain regions beyond the common pattern. To deal with these issues, data-driven methods can be used to detect the presence of sources of inter-subject variability that might be hard to identify and therefore model a priori...
December 7, 2016: Cortex; a Journal Devoted to the Study of the Nervous System and Behavior
George Chahine, Anja Richter, Sarah Wolter, Roberto Goya-Maldonado, Oliver Gruber
Advances in functional brain imaging have improved the search for potential endophenotypic markers in schizophrenia. Here, we employed independent component analysis (ICA) and dynamic causal modeling (DCM) in resting state fMRI on a sample of 35 schizophrenia patients, 20 first-degree relatives and 35 control subjects. Analysis on ICA-derived networks revealed increased functional connectivity between the left frontoparietal network (FPN) and left temporal and parietal regions in schizophrenia patients (P < 0...
December 23, 2016: Human Brain Mapping
Elizabeth DuPre, Wen-Ming Luh, R Nathan Spreng
The default network is involved in self-generated thought, a class of cognition that includes autobiographical memory, prospection, and reasoning about the mental states of others. We collected a replication sample of Spreng and Grady (J Cogn. Neurosci. 22, 1112-1123, 2010), confirming that the default network differentially supports each of these forms of self-generated thought. Here we describe this dataset of multi-echo fMRI data in 31 young adults during autobiographical remembering, imagining, and mentalizing; we also provide an additional resting-state scan for each subject...
December 20, 2016: Scientific Data
Olga Kepinska, Mischa de Rover, Johanneke Caspers, Niels O Schiller
In an effort to advance the understanding of brain function and organisation accompanying second language learning, we investigate the neural substrates of novel grammar learning in a group of healthy adults, consisting of participants with high and average language analytical abilities (LAA). By means of an Independent Components Analysis, a data-driven approach to functional connectivity of the brain, the fMRI data collected during a grammar-learning task were decomposed into maps representing separate cognitive processes...
December 16, 2016: Behavioural Brain Research
Jia Liu, Ben A Duffy, David Bernal-Casas, Zhongnan Fang, Jin Hyung Lee
A large number of fMRI studies have shown that the temporal dynamics of evoked BOLD responses can be highly heterogeneous. Failing to model heterogeneous responses in statistical analysis can lead to significant errors in signal detection and characterization and alter the neurobiological interpretation. However, to date it is not clear that, out of a large number of options, which methods are robust against variability in the temporal dynamics of BOLD responses in block-design studies. Here, we used rodent optogenetic fMRI data with heterogeneous BOLD responses and simulations guided by experimental data as a means to investigate different analysis methods' performance against heterogeneous BOLD responses...
December 16, 2016: NeuroImage
César Caballero-Gaudes, Richard C Reynolds
Blood oxygen-level-dependent functional magnetic resonance imaging (BOLD fMRI) has rapidly become a popular technique for the investigation of brain function in healthy individuals, patients as well as in animal studies. However, the BOLD signal arises from a complex mixture of neuronal, metabolic and vascular processes, being therefore an indirect measure of neuronal activity, which is further severely corrupted by multiple non-neuronal fluctuations of instrumental, physiological or subject-specific origin...
December 9, 2016: NeuroImage
Jonathan C Ipser, Anne Uhlmann, Paul Taylor, Brian H Harvey, Don Wilson, Dan J Stein
Chronic methamphetamine use is associated with executive functioning deficits that suggest dysfunctional cognitive control networks (CCNs) in the brain. Likewise, abnormal connectivity between intrinsic CCNs and default mode networks (DMNs) has also been associated with poor cognitive function in clinical populations. Accordingly, we tested the extent to which methamphetamine use predicts abnormal connectivity between these networks, and whether, as predicted, these abnormalities are compounded in patients with a history of methamphetamine-associated psychosis (MAP)...
December 5, 2016: Addiction Biology
Michael Lührs, Bettina Sorger, Rainer Goebel, Fabrizio Esposito
OBJECTIVE: Brain-computer interfaces (BCIs) implemented with real-time functional magnetic resonance imaging (rt-fMRI) use fMRI time-courses from predefined regions of interest (ROIs). To reach best performances, localizer experiments and on-site expert supervision are required for ROI definition. To automate this step, we developed two unsupervised computational techniques based on the general linear model (GLM) and independent component analysis (ICA) of rt-fMRI data, and compared their performances on a communication BCI...
November 30, 2016: Journal of Neural Engineering
Bo-Yong Park, Jisu Hong, Seung-Hak Lee, Hyunjin Park
Attention deficit hyperactivity disorder (ADHD) is a pervasive neuropsychological disorder that affects both children and adolescents. Child and adolescent ADHD patients exhibit different behavioral symptoms such as hyperactivity and impulsivity, but not much connectivity research exists to help explain these differences. We analyzed openly accessible resting-state functional magnetic resonance imaging (rs-fMRI) data on 112 patients (28 child ADHD, 28 adolescent ADHD, 28 child normal control (NC), and 28 adolescent NC)...
2016: Frontiers in Human Neuroscience
Michele Allegra, Shima Seyed-Allaei, Fabrizio Pizzagalli, Fahimeh Baftizadeh, Marta Maieron, Carlo Reverberi, Alessandro Laio, Daniele Amati
There is growing interest in the description of short-lived patterns in the spatiotemporal cortical activity monitored via neuroimaging. Most traditional analysis methods, designed to estimate relatively long-term brain dynamics, are not always appropriate to capture these patterns. Here we introduce a novel data-driven approach for detecting short-lived fMRI brain activity patterns. Exploiting Density Peak Clustering (Rodriguez and Laio [2014]), our approach reveals well localized clusters by identifying and grouping together voxels whose time-series are similar, irrespective of their brain location, even when very short time windows (∼10 volumes) are used...
November 23, 2016: Human Brain Mapping
Victor M Vergara, Jingyu Liu, Eric D Claus, Kent Hutchison, Vince Calhoun
Alcohol and nicotine intake result in neurological alterations at the circuit level. Resting state functional connectivity has shown great potential in identifying these alterations. However, current studies focus on specific seeds and leave out many brain regions where effects might exist. The present study uses a data driven technique for brain segmentation covering the whole brain. Functional magnetic-resonance-imaging (fMRI) data were collected from 188 subjects:51 non-substance consumption controls (CTR), 36 smoking-and-drinking subjects (SAD), 28 drinkers (DRN), and 73 smokers (SMK)...
November 15, 2016: NeuroImage
Robert Darkow, Andrew Martin, Anna Würtz, Agnes Flöel, Marcus Meinzer
Non-invasive transcranial direct current stimulation (tDCS) can enhance recovery after stroke. However, fundamental knowledge about how tDCS impacts neural processing in the lesioned human brain is currently lacking. In the present study, it was investigated how tDCS modulates brain function in patients with post-stroke language impairment (aphasia). In a cross-over, randomized trial, patients named pictures of common objects during functional magnetic resonance imaging (fMRI). Concurrently, excitatory (anodal-) or sham-tDCS (1 mA, 20 min, or 30 s, respectively) was administered to the left primary motor cortex, a montage with demonstrated potential to improve aphasic language...
November 11, 2016: Human Brain Mapping
Erlend S Dørum, Dag Alnæs, Tobias Kaufmann, Geneviève Richard, Martina J Lund, Siren Tønnesen, Markus H Sneve, Nina C Mathiesen, Øyvind G Rustan, Øivind Gjertsen, Sigurd Vatn, Brynjar Fure, Ole A Andreassen, Jan Egil Nordvik, Lars T Westlye
INTRODUCTION: Multiple object tracking (MOT) is a powerful paradigm for measuring sustained attention. Although previous fMRI studies have delineated the brain activation patterns associated with tracking and documented reduced tracking performance in aging, age-related effects on brain activation during MOT have not been characterized. In particular, it is unclear if the task-related activation of different brain networks is correlated, and also if this coordination between activations within brain networks shows differential effects of age...
November 2016: Brain and Behavior
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