BOLD responses in human auditory cortex are more closely related to transient MEG responses than to sustained ones

• Verfasst von: Gutschalk, Alexander [VerfasserIn]
• Verfasst von: Hämäläinen, Matti [VerfasserIn]
• Verfasst von: Melcher, Jennifer R. [VerfasserIn]
• Titel: BOLD responses in human auditory cortex are more closely related to transient MEG responses than to sustained ones
• Verf.angabe: Alexander Gutschalk, Matti S. Hämäläinen, and Jennifer R. Melcher
• E-Jahr: 2010
• Jahr: 27. January 27, 2010
• Umfang: 12 S.
• Fussnoten: Gesehen am 02.06.2023
• Titel Quelle: Enthalten in: Journal of neurophysiology
• Ort Quelle: Bethesda, Md. : Soc., 1938
• Jahr Quelle: 2010
• Band/Heft Quelle: 103(2010), 4, Seite 2015-2026
• ISSN Quelle: 1522-1598
• DOI: doi:10.1152/jn.01005.2009
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1847344496

Abstract

Blood oxygen level dependent-functional magnetic resonance imaging (BOLD-fMRI) and magnetoencephalographic (MEG) signals are both coupled to postsynaptic potentials, although their relationship is incompletely understood. Here, the wide range of BOLD-fMRI and MEG responses produced by auditory cortex was exploited to better understand the BOLD-fMRI/MEG relationship. Measurements of BOLD and MEG responses were made in the same subjects using the same stimuli for both modalities. The stimuli, 24-s sequences of click trains, had duty cycles of 2.5, 25, 72, and 100%. For the 2.5% sequence, the BOLD response was elevated throughout the sequence, whereas for 100%, it peaked after sequence onset and offset and showed a diminished elevation in between. On the finer timescale of MEG, responses at 2.5% consisted of a complex of transients, including N1m, to each click train of the sequence, whereas for 100% the only transients occurred at sequence onset and offset between which there was a sustained elevation in the MEG signal (a sustained field). A model that separately estimated the contributions of transient and sustained MEG signals to the BOLD response best fit BOLD measurements when the transient contribution was weighted 8- to 10-fold more than the sustained one. The findings suggest that BOLD responses in the auditory cortex are tightly coupled to the neural activity underlying transient, not sustained, MEG signals.