| dc.contributor.author | Whittingstall, Kevin S. | en_US |
| dc.date.accessioned | 2014-10-21T12:36:32Z | |
| dc.date.available | 2006 | |
| dc.date.issued | 2006 | en_US |
| dc.identifier.other | AAINR16720 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/54811 | |
| dc.description | In the past 20 years, research in brain functionality has substantially increased. Tools such as the electroencephalogram (EEG) and functional magnetic resonance imaging (FMRI) have made it possible to non-invasively measure brain function. The temporal resolution of EEG is superior to that of FMRI, and it is generally believed that the spatial resolution of FMRI is superior to that of the EEG. The combination of these two modalities in neuroimaging studies is therefore important, as it may provide complimentary information regarding brain function. Although EEG and FMRI are sensitive to very different physiological phenomena (synaptic and hemodynamic events, respectively) the exact relationship between the sources of EEG and FMRI remains unknown. This raises an important question: is EEG blind to events detected by FMRI or vice-versa? It is anticipated that a better understanding of this relationship will lend additional insight into brain function. | en_US |
| dc.description | The focus of this thesis is to study the relationship between the sources of EEG and FMRI. This was done by making two sets of visual evoked potential (VEP) and FMRI measurements on healthy participants, and one set of VEP/FMRI measurements on patients with uni-lateral glaucoma. The results from the first set of VEP/FMRI measurements show that the location of the N75 VEP source is near the positive FMRI response (+BOLD), while the P100 source is near the negative FMRI response (-BOLD). In the second set of VEP measurements, we show that the location of the N75 and +BOLD source are more sensitive to changes in stimulus position than the P100 and -BOLD source. In the final set of measurements, the results show that both VEP & FMRI are sensitive to visual field impairment brought on by glaucoma. It is also shown that the N75 component of the VEP and the +BOLD response of FMRI are the best markers for identifying the effects of glaucoma in the visual cortex. Taken together, the results from this thesis show that there exists a strong relationship between the sources that elicit the VEP and FMRI responses. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 2006. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Engineering, Biomedical. | en_US |
| dc.subject | Biophysics, Medical. | en_US |
| dc.title | Multi-modal approach to localizing sources in the human brain. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
