Search results for "FMRI"
showing 10 items of 168 documents
Connectivity patterns during music listening: Evidence for action-based processing in musicians
2017
Musical expertise is visible both in the morphology and functionality of the brain. Recent research indicates that functional integration between multi-sensory, somato-motor, default-mode (DMN), and salience (SN) networks of the brain differentiates musicians from non-musicians during resting state. Here, we aimed at determining whether brain networks differentially exchange information in musicians as opposed to non-musicians during naturalistic music listening. Whole-brain graph-theory analyses were performed on participants' fMRI responses. Group-level differences revealed that musicians' primary hubs comprised cerebral and cerebellar sensorimotor regions whereas non-musicians' dominant …
An efficient functional magnetic resonance imaging data reduction strategy using neighborhood preserving embedding algorithm
2021
High dimensionality data have become common in neuroimaging fields, especially group-level functional magnetic resonance imaging (fMRI) datasets. fMRI connectivity analysis is a widely used, powerful technique for studying functional brain networks to probe underlying mechanisms of brain function and neuropsychological disorders. However, data-driven technique like independent components analysis (ICA), can yield unstable and inconsistent results, confounding the true effects of interest and hindering the understanding of brain functionality and connectivity. A key contributing factor to this instability is the information loss that occurs during fMRI data reduction. Data reduction of high …
Discovering hidden brain network responses to naturalistic stimuli via tensor component analysis of multi-subject fMRI data
2021
The study of brain network interactions during naturalistic stimuli facilitates a deeper understanding of human brain function. To estimate large-scale brain networks evoked with naturalistic stimuli, a tensor component analysis (TCA) based framework was used to characterize shared spatio-temporal patterns across subjects in a purely data-driven manner. In this framework, a third-order tensor is constructed from the timeseries extracted from all brain regions from a given parcellation, for all participants, with modes of the tensor corresponding to spatial distribution, time series and participants. TCA then reveals spatially and temporally shared components, i.e., evoked networks with the …
Mutual Information Analysis of Brain-Body Interactions during different Levels of Mental stress
2019
In this work, we analyze brain-heart interactions during different mental states computing mutual information (MI) between the dynamic activity of different physiological systems. In 18 healthy subjects monitored in a relaxed resting state and during a mental arithmetic and a serious game task, multichannel EEG, one lead ECG, respiration and blood volume pulse were collected via wireless non-invasive biosensors. From these signals, synchronous 300-second time series were extracted measuring brain activity via the δ, θ, α, and β EEG power, and activity of the body district via the ECG R-R interval η, the respiratory amplitude ϱ and the pulse arrival time π. MI was computed using a linear est…
Assessment of Functional Connectome in End-Stage Organ Disease Patients After Life-Threatening Surgery
2020
Purpose The purpose of this study was to assess the organization of intrinsic functional brain networks (functional connectome) in neurologically asymptomatic patients with end-stage organ disease who had undergone major surgery for life-threating conditions and compare it to a control group. Materials and Methods Resting-state functional magnetic resonance imaging (rest-fMRI) was performed in 10 adult, post-operative patients with end-stage organ disease. The patients (7 men, 3 women, mean age 57.9 ± 7.4 years) had undergone: n=4 coronary artery bypass graft for heart failure, n=2 orthotopic liver transplantation for non-alcoholic cirrhotic liver failure, n=3 mitral valve repair for heart …
Stronger proprioceptive BOLD-responses in the somatosensory cortices reflect worse sensorimotor function in adolescents with and without cerebral pal…
2020
Graphical abstract
Regional Cerebral Blood Flow in Cases of Brain Tumor
1969
The present series consists of 21 patients with brain tumors: 12 malignant gliomas, 4 oligo- dendro gliomas, 3 meningeomas and 2 metastases, studied by the133Xe-gamma-clearance rCBF method. In 16 patients at least 3 determinations of rCBF were performed: a) in the resting state, R; b) during hyperventilation, HV, and c) during hypertension, HT. Of the remaining 5 patients, 1 was studied only during R, while the other 4 were submitted either to HV or to HT additionally to the R study. The average age of this series of patients was 47 years, the youngest being 19 and the oldest 64. rCBF studies had to be performed under general anesthesia (N2O + O2, Engstrom respirator) in 5 instances in whic…
Effect of Vestibular Rehabilitation on Spontaneous Brain Activity in Patients With Vestibular Migraine: A Resting-State Functional Magnetic Resonance…
2019
Previous studies have shown that vestibular migraine (VM) is a cerebral disease with recurrent vertigo. Vestibular rehabilitation (VR) is an effective type of physical therapy for minimizing vestibular symptoms, as it improves vestibular compensation in patients with VM. Currently, the cerebral regions that are associated with the pathogenesis of VM are largely unknown. To further understand the underlying mechanisms of VM, we performed resting-state functional magnetic resonance imaging (fMRI) before and after 1 month of VR in 14 patients with VM. The Dizziness Handicap Inventory (DHI), the 36-Item Short-Form Health Survey (SF-36), the Hamilton Depression Scale (HAMD) and the Hamilton Anxi…
Cortical and Cerebellar Oscillatory Responses to Postural Instability in Parkinson's Disease
2021
Introduction: Posture and balance dysfunctions critically impair activities of daily living of patients with progressing Parkinson's disease (PD). However, the neural mechanisms underlying postural instability in PD are poorly understood, and specific therapies are lacking. Previous electrophysiological studies have shown distinct cortical oscillations with a significant contribution of the cerebellum during postural control tasks in healthy individuals.Methods: We investigated cortical and mid-cerebellar oscillatory activity via electroencephalography (EEG) during a postural control task in 10 PD patients with postural instability (PDPI+), 11 PD patients without postural instability (PDPI–…
Music and Emotions in the Brain: Familiarity Matters
2011
The importance of music in our daily life has given rise to an increased number of studies addressing the brain regions involved in its appreciation. Some of these studies controlled only for the familiarity of the stimuli, while others relied on pleasantness ratings, and others still on musical preferences. With a listening test and a functional magnetic resonance imaging (fMRI) experiment, we wished to clarify the role of familiarity in the brain correlates of music appreciation by controlling, in the same study, for both familiarity and musical preferences. First, we conducted a listening test, in which participants rated the familiarity and liking of song excerpts from the pop/rock repe…