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Localization of Brain Activity in Electroencephalography Data during Brain-Computer Interface Operation

Hjärtquist, Oskar LU (2011) EEM820 20112
Department of Biomedical Engineering
Abstract
In this Master's thesis I present a means of finding active sources of cortical electrical activity from electroencephalogram (EEG) data acquired during operation of a brain-computer interface (BCI). A novel subspace-based technique was used to suppress spatially correlated EEG interference sources, followed by a technique that estimates the source parameters with a near maximum likelihood performance. These sources are found to correlate with event-related potentials (ERPs) and are thus hypothesized to be responsible for the N200 and P300 ERPs. The source localization technique was tested on EEG data of 6 able-bodied subjects, and my analysis underlines consistencies and variation of brain activity locations both within and across... (More)
In this Master's thesis I present a means of finding active sources of cortical electrical activity from electroencephalogram (EEG) data acquired during operation of a brain-computer interface (BCI). A novel subspace-based technique was used to suppress spatially correlated EEG interference sources, followed by a technique that estimates the source parameters with a near maximum likelihood performance. These sources are found to correlate with event-related potentials (ERPs) and are thus hypothesized to be responsible for the N200 and P300 ERPs. The source localization technique was tested on EEG data of 6 able-bodied subjects, and my analysis underlines consistencies and variation of brain activity locations both within and across subjects. Results are compared to literature and results using other techniques and the new methods show promise in localizing brain activity when dual-condition datasets are available. (Less)
Please use this url to cite or link to this publication:
author
Hjärtquist, Oskar LU
supervisor
organization
course
EEM820 20112
year
type
H2 - Master's Degree (Two Years)
subject
keywords
P300), N200, Event-related potential (ERP, Noise Subspace Fitting (NSF), Null Space Projection (NP), Localization, Dipole source, Elec- troencephalography (EEG), Brain-Computer Interface (BCI) Speller
language
English
additional info
2011-09
id
2275108
date added to LUP
2012-01-02 13:13:52
date last changed
2014-10-08 14:47:00
@misc{2275108,
  abstract     = {In this Master's thesis I present a means of finding active sources of cortical electrical activity from electroencephalogram (EEG) data acquired during operation of a brain-computer interface (BCI). A novel subspace-based technique was used to suppress spatially correlated EEG interference sources, followed by a technique that estimates the source parameters with a near maximum likelihood performance. These sources are found to correlate with event-related potentials (ERPs) and are thus hypothesized to be responsible for the N200 and P300 ERPs. The source localization technique was tested on EEG data of 6 able-bodied subjects, and my analysis underlines consistencies and variation of brain activity locations both within and across subjects. Results are compared to literature and results using other techniques and the new methods show promise in localizing brain activity when dual-condition datasets are available.},
  author       = {Hjärtquist, Oskar},
  keyword      = {P300),N200,Event-related potential (ERP,Noise Subspace Fitting (NSF),Null Space Projection (NP),Localization,Dipole source,Elec- troencephalography (EEG),Brain-Computer Interface (BCI) Speller},
  language     = {eng},
  note         = {Student Paper},
  title        = {Localization of Brain Activity in Electroencephalography Data during Brain-Computer Interface Operation},
  year         = {2011},
}