Coupling Between Neuronal Firing, Field Potentials, and fMRI in Human Auditory Cortex
Roy Mukamel,1
Hagar Gelbard,1
Amos Arieli,1
Uri Hasson,2
Itzhak Fried,3,4*
Rafael Malach1*
Functional magnetic resonance imaging (fMRI) is an important tool for investigating human brain function, but the relationship between the hemodynamically based fMRI signals in the human brain and the underlying neuronal activity is unclear. We recorded single unit activity and local field potentials in auditory cortex of two neurosurgical patients and compared them with the fMRI signals of 11 healthy subjects during presentation of an identical movie segment. The predicted fMRI signals derived from single units and the measured fMRI signals from auditory cortex showed a highly significant correlation (r = 0.75, P < 10–47). Thus, fMRI signals can provide a reliable measure of the firing rate of human cortical neurons.
1 Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel.
2 Center for Neural Science, New York University, New York, NY 10003, USA.
3 Division of Neurosurgery, David Geffen School of Medicine, and Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles (UCLA), Los Angeles, CA 90095, USA.
4 Functional Neurosurgery Unit, Tel Aviv Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
* To whom correspondence should be addressed. E-mail: rafi.malach{at}weizmann.ac.il (R.M.); ifried{at}mednet.ucla.edu (I.F.)
