1. fMRI of motor control (Drs. Ashe and Georgopoulos)

2. fMRI of language

3. fMRI of Cerebellum during movements (with Dr. Ebner)

4. First fMRI of Dentate Nuclei in Cerebellum during Cognitive Tasks (with Dr. Strick)

5. First fMRI of mental rotation (with Dr. Georgopoulos at VA Medical Center)

1. fMRI of motor control (Drs. Ashe and Georgopoulos):

Following to successful fMRI studies during visual stimation, we started to collaborate to map functional areas of motor control and motor learning. The first paper was published at Journal of Neurophysiolgy as a cover at 1993, and then subsequent paper was published at Science at the same year.

Kim, S.-G., Ashe, J., Georgopoulos, A., Merkle, H., Ellermann, J.M., Menon, R.S., Ogawa, S. and Ugurbil, K. ``Functional Imaging of Human Motor Cortex at High Magnetic Field'', J. Neurophysiol., 69: 297-302, 1993. Medline

 
Kim, S.-G., Ashe, J., Hendrich, K., Ellermann, J.M., Merkle, H., Ugurbil, K. and Georgopoulos, A.P. ``Functional Magnetic Resonance Imaging of Motor Cortex: Hemispheric Asymmetry and Handedness'' Science, 261: 615-617, 1993. Medline
 

Kim, S.-G., Jennings, J.E., Strupp, J.P., Andersen, P. and Ugurbil, K. ``Functional MRI of Human Motor Cortices during Overt and Imaged Finger Movements'', Int. J. Imaging Sys. Tech., 6: 271-279, 1995.
 

P. Dassonville, X.-H. Zhu, K. Ugurbil, S.-G. Kim and J. Ashe, "Functional activation in motor cortex reflects the direction and the degree of handedness", Proc. Natl. Acad. Sci., USA., 94: 14015-14018, 1997. Medline  (PDF file)
 

P. Dassonville, S.M. Lewis, X.-H. Zhu, K. Ugurbil, S.-G. Kim, and J. Ashe, "Effects of stimulus predictability on cortical motor activation", Neuroscience Research, 32(1):65-74, 1998. Medline  (PDF file).
 
 

2.  fMRI of language:

The first functional images of language production were obtained by us.

Hinke, R.M., Hu, X., Stillman, A.E., Kim, S.-G., Merkle, H., Salmi, R. and Ugurbil, K. ``Functional Magnetic Resonance Imaging of Broca's Area During Internal Speech'', NeuroReport, 4: 675-678, 1993 Medline.

3.  fMRI of Cerebellum during movements (with Dr. Ebner):

The first functional imaging of cerebellum was obtained during simple movement, and visuomotor transformation.

Ellermann, J., Flament, D., Kim, S.-G., Fu, Q.-G., Merkle, H. and Ugurbil, ``Spatial patterns of functional activation of the cerebellum investigated using high field (4 T) MRI. ', NMR in Biomedicine, 7: 63-68, 1994 Medline.

Flament, D., Ellermann, J.M., Kim, S.-G., Ugurbil, K. and Ebner, T.J., ``Temporal changes in cerebellar activation during motor errors and the learning of a visuomotor dissociation task, revealed using high-field functional magnetic resonance imaging'', Human Brain Mapping, 4: 210-226, 1996.
 

4. First fMRI of Dentate Nuclei in Cerebellum during Cognitive Tasks (with Dr. Strick):

The first mapping of nuclei was obtained by us using high resolution functional imaging (1.25 x 1.25 mm2 spatial resolution). The important observation was the involvement of cerebellum to cognition. Clearly cerebellar output, dentate nuclei were active more during cognitive puzzle tasks that during simple visually-guided movements. This work was published at Science.

Kim, S.-G., Ugurbil, K. and Strick, P. ``Activation of a Cerebellar Output Nucleus during Cognitive Processing'', Science, 265: 949 - 951, 1994 Medline.

5. First fMRI of mental rotation (with Dr. Georgopoulos at VA Medical Center):

Functional imaging of cognitive brain functions was obtained with collaboration with Apostolos Georgopoulos. Especially, our group used mental rotation as a test task to develop single-trial fMRI, because reaction times are relative long (an order of a few seconds) and vary trial-by-trial.  Further, by using single-trial fMRI during mental rotation, we found secondary motor areas (such as supplmentary motor, dorsal premotor) are involved to mental rotation.

A pair of 3-D objects (based on Shepard and Metzler's paper) was shown to subjects. Then, subjects had to decide two 3-D objects were same or mirror-images by pushing one of two buttons. Reaction time and accuracy of responses were recorded.

Tagaris, G.A., Kim, S.-G., Strupp, J.P., Andersen. P., Ugurbil, K. and Georgopoulos, A.P., ``Quantitative Relations between Parietal Activation and Performance in Mental Rotation'', NeuroReport, 7: 773-776, 1996 Medline.

Tagaris, G.A., Kim, S.-G., Strupp, J.P., Andersen. P., Ugurbil, K. and Georgopoulos, A.P. ``Mental Rotation studied by Functional Magnetic Resonance Imaging at High Field (4 Tesla): Performance and Cortical Activation'', J. Cognitive Neuroscience, 9: 419-432, 1997.

W. Richter, K. Ugurbil, A. Georgopoulos, and S.-G. Kim, ``Time-Resolved fMRI of Mental Rotation, NeuroReport, 8: 3697-3702, 1997 Medline.

G.A. Tagaris, W. Richter, S.-G. Kim, G. Pellizzer, P. Andersen, K. Ugurbil, and A.P. Georgopoulos, "Functional magnetic resonance imaging of mental rotation and memory scanning: a multidimensional analysis of brain activation patterns", Brain Research Reviews, 26: 106-112, 1998 Medline.

W. Richter, R. Somorijai, R. Summers, M. Jarmasz, R.S. Menon, J.S. Gati, A.P. Georgopoulos, C. Tegeler, K. Ugurbil, S.-G. Kim, "Motor area activity during mental rotation studied by time-resolved single-trial fMRI", J. Cogn. Neurosci., 12(2): 310-320, 2000 Medline (PDF file).
 
 

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