Influence of dense-array EEG cap on fMRI signal

Copyright © 2011 Wiley Periodicals, Inc..

Dense-array (>64 channel) electroencephalography (EEG) systems are increasingly being used in simultaneous EEG-functional magnetic resonance imaging (fMRI) studies. However, with increasing channel count, dense-array EEG caps can induce more severe signal dropout in the MRI images than conventional systems due to the radiofrequency shielding effect of the denser wire bundle. This study investigates the influence of a 256-channel EEG cap on MRI image quality and detection sensitivity of blood oxygen level dependent fMRI signal. A theoretical model is first established to describe the impact of the EEG cap on anatomic signal, noise, signal-to-noise ratio, and contrast-to-noise ratio of blood oxygen level dependent signal. Seven subjects were scanned to measure and compare the T(2)-weighted image quality and fMRI detection sensitivity with and without the EEG cap using an auditory/visual/sensorimotor task. The results show that the dense-array EEG cap can substantially reduce the anatomic signal in the brain areas (visual cortex) near the conducting wires (average percent decrease ≈ 38%). However, the image signal-to-noise ratio with and without the EEG cap was comparable (percent decrease < 8%, not statistically significant), and there was no statistically significant difference in the extent of blood oxygen level dependent activation. This suggests that the ability to detect fMRI signal is nearly unaffected by dense-array EEG caps in simultaneous EEG-fMRI experiments.

Medienart:

E-Artikel

Erscheinungsjahr:

2012

Erschienen:

2012

Enthalten in:

Zur Gesamtaufnahme - volume:68

Enthalten in:

Magnetic resonance in medicine - 68(2012), 3 vom: 01. Sept., Seite 807-15

Sprache:

Englisch

Beteiligte Personen:

Luo, Qingfei [VerfasserIn]
Glover, Gary H [VerfasserIn]

Links:

Volltext

Themen:

Journal Article
Research Support, N.I.H., Extramural

Anmerkungen:

Date Completed 25.01.2013

Date Revised 21.10.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/mrm.23299

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM213778793