The overall aim of this proposal is to establish the relationships between changes in BOLD signals obtained with functional magnetic resonance imaging (fMR) and changes in activity of neurons during the same cognitive measures, at the same sites, in the same subjects in human association cortex. The proposal utilizes a unique clinical opportunity, patients undergoing surgery for epilepsy with a technique where they are awake under local anesthesia for a portion of the operation. In that context we have previously recorded neuronal activity, both action potentials (AP) and overlying electroencephalogram (ECoG) from lateral temporal association cortex during recent verbal memory, finding that a substantial proportion of neurons changed the frequency of AP activity with that task. Both the fMR literature and our preliminary fMR data show fMR changes in lateral temporal cortex with recent memory measures. Having developed a recent verbal memory measure suitable for both fMR and intraoperative recording, we propose investigating the spatial and temporal relation between AP, local field potential (LFP), ECoG and fMR. Hypotheses to be tested include a closer relation between fMR and LFP than AP activity, based on findings reported from nonhuman studies, and specificity of fMR changes to sites with sustained patterns of AP activity during memory. These studies provide a unique window into how neural activity is reflected in changes in BOLD fMR during higher-level cognitive measures.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Research Project (R01)
Project #
5R01EB002663-02
Application #
6802020
Study Section
Special Emphasis Panel (ZRG1-SRB (53))
Program Officer
Haller, John W
Project Start
2003-09-20
Project End
2007-07-31
Budget Start
2004-08-01
Budget End
2005-07-31
Support Year
2
Fiscal Year
2004
Total Cost
$312,356
Indirect Cost
Name
University of Washington
Department
Neurosurgery
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Zamora, Leona; Corina, David; Ojemann, George (2016) Human temporal cortical single neuron activity during working memory maintenance. Neuropsychologia 86:1-12
Zanos, Stavros; Zanos, Theodoros P; Marmarelis, Vasilis Z et al. (2012) Relationships between spike-free local field potentials and spike timing in human temporal cortex. J Neurophysiol 107:1808-21
Ojemann, George A; Corina, David P; Corrigan, Neva et al. (2010) Neuronal correlates of functional magnetic resonance imaging in human temporal cortex. Brain 133:46-59
Ojemann, George A; Schoenfield-McNeill, Julie; Corina, David (2009) The roles of human lateral temporal cortical neuronal activity in recent verbal memory encoding. Cereb Cortex 19:197-205
Lucas 2nd, Timothy H; McKhann 2nd, Guy M; Ojemann, George A (2004) Functional separation of languages in the bilingual brain: a comparison of electrical stimulation language mapping in 25 bilingual patients and 117 monolingual control patients. J Neurosurg 101:449-57
Ojemann, George A; Schoenfield-McNeill, Julie; Corina, David (2004) Different neurons in different regions of human temporal lobe distinguish correct from incorrect identification or memory. Neuropsychologia 42:1383-93