Ultra high-resolution fMRI in monkeys with implanted RF coils

Nikos K. Logothetis, Hellmut Merkle, Mark Augath, Torsten Trinath, Kâmil Uǧurbil

Research output: Contribution to journalArticlepeer-review

126 Scopus citations


Spatiotemporally resolved functional MRI (fMRI) in animals can reveal how wide-spread neural networks are organized and accompanying electrophysiological recordings can show how small neural assemblies contribute to this organization. Here we present a novel technique that yields high-resolution structural and functional images of the monkey brain with small, tissue-compatible, intraosteally implantable radiofrequency coils. Voxel sizes as small as 0.0113 μl with high signal-to-noise and contrast-to-noise ratios were obtained, revealing both structural and functional cortical architecture in great detail. Up to a certain point, contrast sensitivity increased with decreasing voxel size, probably because of the decreased partial volume effects. Spatial specificity was demonstrated by the lamina-specific activation in experiments comparing responses to moving and flickering stimuli. The implications of this technique for combined fMRI/electrophysiology experiments and its limitations in terms of spatial coverage are discussed.

Original languageEnglish (US)
Pages (from-to)227-242
Number of pages16
Issue number2
StatePublished - Jul 18 2002

Bibliographical note

Funding Information:
We thank Drs. David Leopold and Natasha Sigala for reading the manuscript and for many useful suggestions. Many thanks to Ms. Diane Blaurock for English corrections and editing, and to Stefan Weber for fine-mechanic work. This research was supported by the Max Planck Society and NIH grant RR08079, to K. Uǧurbil.

Fingerprint Dive into the research topics of 'Ultra high-resolution fMRI in monkeys with implanted RF coils'. Together they form a unique fingerprint.

Cite this