QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, June 27, 2007, 27(26):6892-6902; doi:10.1523/JNEUROSCI.0445-07.2007

This Article Full Text Full Text (PDF) Supplemental Data Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Related articles in J. Neurosci. Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (9) Citing Articles via Google Scholar Google Scholar Articles by Moon, C.-H. Articles by Kim, S.-G. Search for Related Content PubMed PubMed Citation Articles by Moon, C.-H. Articles by Kim, S.-G.

 Previous Article  |  Next Article 

Behavioral/Systems/Cognitive
Neural Interpretation of Blood Oxygenation Level-Dependent fMRI Maps at Submillimeter Columnar Resolution

Chan-Hong Moon,^1 * Mitsuhiro Fukuda,^1 * Sung-Hong Park,¹ and Seong-Gi Kim^1,2

Departments of ¹Radiology and ²Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15203

Correspondence should be addressed to Seong-Gi Kim, Department of Radiology, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203. Email: kimsg{at}pitt.edu

Whether conventional gradient-echo (GE) blood oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is able to map submillimeter-scale functional columns remains debatable mainly because of the spatially nonspecific large vessel contribution, poor sensitivity and reproducibility, and lack of independent evaluation. Furthermore, if the results from optical imaging of intrinsic signals are directly applicable, regions with the highest BOLD signals may indicate neurally inactive domains rather than active columns when multiple columns are activated. To examine these issues, we performed BOLD fMRI at a magnetic field of 9.4 tesla to map orientation-selective columns of isoflurane-anesthetized cats. We could not convincingly map orientation columns using conventional block-design stimulation and differential analysis method because of large fluctuations of signals. However, we successfully obtained GE BOLD iso-orientation maps with high reproducibility (r = 0.74) using temporally encoded continuous cyclic orientation stimulation with Fourier data analysis, which reduces orientation-nonselective signals such as draining artifacts and is less sensitive to signal fluctuations. We further reduced large vessel contribution using the improved spin-echo (SE) BOLD method but with overall decreased sensitivity. Both GE and SE BOLD iso-orientation maps excluding large pial vascular regions were significantly correlated to maps with a known neural interpretation, which were obtained in contrast agent-aided cerebral blood volume fMRI and total hemoglobin-based optical imaging of intrinsic signals at a hemoglobin iso-sbestic point (570 nm). These results suggest that, unlike the expectation from deoxyhemoglobin-based optical imaging studies, the highest BOLD signals are localized to the sites of increased neural activity when column-nonselective signals are suppressed.

Key words: CBV; CBF; optical imaging; hemodynamic response; ocular dominance column; orientation column

---

Received Jan. 31, 2007; revised May 16, 2007; accepted May 18, 2007.

Correspondence should be addressed to Seong-Gi Kim, Department of Radiology, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203. Email: kimsg{at}pitt.edu

Related articles in J. Neurosci.:

This Week in The Journal

J. Neurosci. 2007 27: i. [Full Text]  

This article has been cited by other articles:

				Y. B. Sirotin, E. M. C. Hillman, C. Bordier, and A. Das Spatiotemporal precision and hemodynamic mechanism of optical point spreads in alert primates PNAS, October 27, 2009; 106(43): 18390 - 18395. [Abstract] [Full Text] [PDF]

				E. Yacoub, N. Harel, and K. Ugurbil High-field fMRI unveils orientation columns in humans PNAS, July 29, 2008; 105(30): 10607 - 10612. [Abstract] [Full Text] [PDF]

				I. Kahn, J. R. Andrews-Hanna, J. L. Vincent, A. Z. Snyder, and R. L. Buckner Distinct Cortical Anatomy Linked to Subregions of the Medial Temporal Lobe Revealed by Intrinsic Functional Connectivity J Neurophysiol, July 1, 2008; 100(1): 129 - 139. [Abstract] [Full Text] [PDF]

				S.-G. Kim and M. Fukuda Lessons from fMRI about Mapping Cortical Columns Neuroscientist, June 1, 2008; 14(3): 287 - 299. [Abstract] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help