Paper Info
Title
High-frequency (600 Hz) population spikes in human EEG delineate thalamic and cortical fMRI activation sites.
Abstract
Functional magnetic resonance imaging (fMRI) measures neural activity indirectly via its slow vascular/metabolic consequences. At a temporal resolution on the order of seconds, fMRI does not reveal the real ‘language of neurons’, spelt out by fast electrical discharges (‘spikes’) which occur on a time scale of milliseconds. In animal studies, these limitations have been addressed by adding invasive electrode measurements to fMRI. Here, we propose to circumvent this ‘inverse problem of fMRI’ by deriving a noninvasive spike measure from recordings of ultrafast electroencephalography (EEG) signals during fMRI. We demonstrate how in response to median nerve stimulation 600 Hz oscillatory EEG signals can be measured reliably during fMRI. These high-frequency bursts (HFBs) are supposed to reflect population spikes in the thalamus and the somatosensory cortex, respectively. We show that distinct fMRI activations in these two generator structures can be attributed to spontaneous HFB fluctuations. Thus, our approach allowed the noninvasive identification of neural processes along the thalamocortical pathway unfolding at a millisecond time scale.
Year
DOI
Venue
2008
10.1016/j.neuroimage.2008.05.026
NeuroImage
Keywords
Field
DocType
active site,electroencephalography,somatosensory cortex,high frequency,inverse problem,temporal resolution,animal studies
Thalamus,Population,Neuroscience,Functional magnetic resonance imaging,Psychology,Neural activity,Somatosensory system,Temporal resolution,Electroencephalography,EEG-fMRI
Journal
Volume
Issue
ISSN
42
2
1053-8119
Citations 
PageRank 
References 
7
0.58
6
Authors
4
Name
Order
Citations
PageRank
Petra Ritter115811.68
Frank Freyer2422.45
Gabriel Curio31220201.67
Arno Villringer447754.45