Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 61 for “"magnetoencephalography"”.
-
Spatial-temporal Source Reconstruction for Magnetoencephalography
Magnetoencephalography (MEG) is a new non-invasive technique for the functional imaging of the human brain. It has been widely used in both research and clinical applications, for it has several superior properties, including a high-temporal resolution with no interference from the bone or the …
-
HEAD MOTION EVALUATION AND CORRECTION IN MAGNETOENCEPHALOGRAPHY
Head motions during magnetoencephalography (MEG) data acquisition lead to inaccuracy in MEG signal localization and statistical sensitivity. Multiple head motion correction methods have been developed and validated to insure the head motion effects are removed, with the aim of improving …
-
Bayesian Methods for Source Separation in Magnetoencephalography
Magnetoencephalography (MEG) is a non-invasive brain imaging modality which localizes the sources of electrical activity within the brain based on measurements of the induced magnetic field outside the head. It has a variety of clinical applications; in particular, when a patient suffering from …
-
Memory-related cognitive modulation of human auditory cortex: Magnetoencephalography-based validation of a computational model
… The experimental approach measures high-density magnetoencephalography (MEG) signals from human participants to investigate the modulation of human auditory evoked responses (AER) induced by the overt processing of auditory STM during task performance. To accomplish this goal, a new signal …
-
A systematic exploration of perceptual and semantic differences in category-specific object-processing using magnetoencephalography
… activation in normal parti¬cipants using magnetoencephalography (MEG). Our experiments explored the temporal processing of objects, as MEG characterises neural activity on the order of milliseconds. Our experiments explored object-processing, including assessing the time-course of ob¬ject …
-
Hyperbolic graph embedding of magnetoencephalography brain networks to study brain alterations in patients with subjective cognitive decline
… brain connectivity graphs derived from magnetoencephalography data to a Poincare disk instead of traditional Euclidean space. The Poincare disk is a negatively curved unit disk that encourages a continuous tree-like (and low-dimensional) embedding where paths between sibling nodes pass …
-
Applications of Granger Causality to Magnetoencephalography Research, Short Trial Time Series Analysis, and the Study of Decision Making
Causality analysis is an approach to time series analysis that is being used increasingly to investigate neuroimaging data. The reason for its popularity is the useful perspective it provides in describing the ordered operations of various brain regions using indirectly and passively measured …
-
Development of Methodologies for the Solution of the Forward Problem in Magnetic-Field Tomography (MFT) Based on Magnetoencephalography (MEG)
… problem in Magnetic field Tomography based on Magnetoencephalography. Throughout the report full aspects of the accurate solution are discussed, including the development of algorithms and methods for realistic brain model, development of realistic neuronal source, computational approaches, and …
-
Phonological and semantic influences on auditory word perception in children with and without reading impairments using magnetoencephalography (MEG) and electroencephalography (EEG)
Children with dyslexia struggle with learning to read despite adequate intelligence, motivation, and schooling. Over the years, there has been a growing consensus about the role of phonological processing in reading disability. Poor readers typically do worse than their normal reading peers on …
-
Characterizing the spatiotemporal profile and the level of abstractness of action representations: neural decoding of magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) data
… three neuroimaging studies in which we used magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) to characterize the temporal dynamics of abstract representations of observed actions (Study 1 and 2), meaning that generalize across lower level dimensions, and to …
-
A finite difference forward model for MEG and EEG
… signals generated by the human brain as seen on magnetoencephalography and electroencephalography machines. The model makes a novel use of the principle of reciprocity combined with Ohm's Law and the Biot Savart Law to build a model of the human magnetoencephalogram that is much faster to compute …
-
The effect of Alzheimer's disease on cortical microcircuits
… (i) assess the reliability and sensitivity of magnetoencephalography evoked responses from a mismatch negativity paradigm to the severity and progression of Alzheimer’s disease and to employ dynamic causal modelling to (ii) reproduce these neurophysiological responses, (iii) test hypotheses of …
-
Multimodal integration of EEG and MEG data using minimum ℓ₂-norm estimates
… integration of electroencephalography (EEG) and magnetoencephalography (MEG) data on the minimum ℓ₂-norm estimates of cortical current densities. We investigated analytically the effect of including EEG recordings in MEG studies versus the addition of new MEG channels. To further confirm these …
-
Words and rules in the brain
… tense generation. Two neuroimaging techniques, magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) were used to test healthy, right-handed subjects who were native speakers of English in a past tense production paradigm, in addition to a lexical access study. The …
-
Deep learning models for the perception of human social interactions
… perception with deep learning models and magnetoencephalography (MEG) data. Specically, I implement dierent deep learning computer vision models and test their performance on a social inter- action detection task as well as their match to neural data from the same task. I nd that detecting …
-
Analysis of beta-band MEG coherence in ASD during direct gaze processing: Relationship to social cognition
… passively viewed direct gaze while undergoing Magnetoencephalography (MEG). Results revealed significant intra- and inter-hemispheric between-group differences in average coherence (1-45 Hz), providing preliminary support for increased long-range left hemisphere coherence and increased …
-
Gamma oscillatory activity in autism spectrum disorder during a face cueing task
… between neurotypicals and ASD as measured by magnetoencephalography (MEG) while performing a gaze cueing task simulating joint attention. Results support lower frontal gamma power in ASD, suggesting that impaired generation of gamma activity in the prefrontal cortex may be involved in …
-
Spatio-temporal analysis in functional brain imaging
… activity from electroencephalography (EEG) and magnetoencephalography (MEG) measurements involves solving an ill-posed inverse problem, where infinitely many source distribution patterns can give rise to identical measurements. This thesis aims to improve the accuracy of source localization by …
-
Integration and characterization of a control and signal processing system for a SERF magnetometer array
… by applications in a variety of areas, including magnetoencephalography (MEG), magnetic anomaly detection (MAD), dynamic measurements of geomagnetic fields, and MRI signal detection. While numerous architectures are being pursued in the development of high sensitivity magnetometers, optical atomic …
-
Setting location priors using beamforming improves model comparison in MEG-DCM
… activity of the brain during experimental tasks. Magnetoencephalography (MEG) allows for the observation of the fast neuronal dynamics necessary to characterize the activity of sources and their interactions. A network representation of these sources and their connections can be formed by mapping …
Page 1 of 4