RT Journal Article SR Electronic T1 High-Resolution Maps of Real and Illusory Tactile Activation in Primary Somatosensory Cortex in Individual Monkeys with Functional Magnetic Resonance Imaging and Optical Imaging JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 9181 OP 9191 DO 10.1523/JNEUROSCI.1588-07.2007 VO 27 IS 34 A1 Chen, Li M. A1 Turner, Gregory H. A1 Friedman, Robert M. A1 Zhang, Na A1 Gore, John C. A1 Roe, Anna W. A1 Avison, Malcolm J. YR 2007 UL http://www.jneurosci.org/content/27/34/9181.abstract AB Although blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) has been widely used to explore human brain function, questions remain regarding the ultimate spatial resolution of positive BOLD fMRI, and indeed the extent to which functional maps revealed by positive BOLD correlate spatially with maps obtained with other high-spatial-resolution mapping techniques commonly used in animals, such as optical imaging of intrinsic signal (OIS) and single-unit electrophysiology. Here, we demonstrate that the positive BOLD signal at 9.4T can reveal the fine topography of individual fingerpads in single-condition activation maps in nonhuman primates. These digit maps are similar to maps obtained from the same animal using intrinsic optical imaging. Furthermore, BOLD fMRI reliably resolved submillimeter spatial shifts in activation in area 3b previously identified with OIS (Chen et al., 2003) as neural correlates of the “funneling illusion.” These data demonstrate that at high field, high-spatial-resolution topographic maps can be achieved using the positive BOLD signal, weakening previous notions regarding the spatial specificity of the positive BOLD signal.