| | Principal Investigators
| Leslie G. Ungerleider, Ph.D. |
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Dr.
Ungerleider received her B.A. degree from the State University
of New York at Binghamton and her Ph.D. degree, with a
major in Experimental Psychology, from New York University.
During her postdoctoral training with Karl Pribram at
Stanford University, she began her work on higher-order
perceptual mechanisms in the cortex of primates. She moved
to the NIMH in 1975, joining Mortimer Mishkin in the Laboratory
of Neuropsychology. Their neurobehavioral work inspired
their theory of ‘two cortical visual systems’,
one specialized for object recognition and the other for
visuospatial perception. In 1995, Dr. Ungerleider became
Chief of the Laboratory
of Brain and Cognition at NIMH. She is a member
of the National Academy of Sciences, the Institute of
Medicine of the National Academy of Sciences, and the
American Academy of Arts and Sciences. In 2001, she was the recipient of the Women in Neuroscience Lifetime Achievement Award and in 2008 she became an NIH Distinguished Investigator |
| Research Interests |
Dr. Ungerleider’s Section has long been devoted to establishing the links between neural structure and cognitive function, especially in the visual modality. Before progress could be made on the cognitive questions, however, it was first necessary to establish the basic organization of extrastriate visual cortex. Thus, most of her early work was devoted to anatomical tracing techniques in macaque monkeys in order to delineate the areas that comprise visual association cortex and their interconnections. By the mid-1990s, she and others had succeeded in mapping much of the monkey extrastriate visual cortex and had outlined some of the major functional systems. With the basic anatomical data in hand, she was then able to address more functional questions. Her work in monkeys shifted to 1) behavioral assessment of selective brain lesions in the cortical areas she had previously mapped, and 2) physiological recordings of neural activity in awake, behaving monkeys. With the advent of functional brain imaging in humans, she also began to re-channel some of her resources that had been used previously for neuroanatomy towards studies of human cortex, using first PET and then fMRI. However, the monkey work has guided many of her hypotheses in the human imaging studies, and findings from the imaging studies have provided a broader, systems-level picture than could have been derived from the monkey work alone. Dr. Ungerleider has recently expanded her monkey program to include monkey fMRI and electrophysiological studies in order to carry on the parallel studies in humans and monkeys for which her lab is recognized.
Her work on visual attention and perception has shown that in a typical scene many different objects compete for neural representation due to the limited processing capacity of the visual system. The competition among multiple objects can be biased by both bottom-up sensory-driven mechanisms and top-down influences, such as selective attention. Although the competition among stimuli for representation is ultimately resolved within visual cortex, the source of top-down biasing signals likely derives from a distributed network of areas in frontal and parietal cortex. This biased competition model of attention suggests that once attentional resources are depleted, no further processing is possible. Dr. Ungerleider’s more recent work has shown that, similar to the processing of other stimulus categories, the processing of stimuli with emotional valence is under top-down control, requiring attentional resources.
Clinical Protocols:
Protocol Number: 93-M-0170
Regional Cerebral Blood Flow Studies of Object Perception, Identification, Localization, and Memory.
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| Representative Selected Recent Publications: |
- Hadj-Bouziane, F., Bell, A.H., Knusten, T.A., Ungerleider, L.G., and Tootell, R.B.H.:
Perception of emotional expression activates regions independent of face selectivity in monkey inferior temporal cortex: a fMRI study.
Proc. Natl. Acad. Sci, 105: 5591-5596, 2008.
- Tootell, R.B.H., Devaney, K.J., Young, J.C., Postelnicu, G., Rajimehr, R., and Ungerleider, L.G.:
fMRI mapping of a morphed continuum of 3D shapes within inferiortemporal cortex.
Proc. Natl. Acad. Sci, USA 105: 3605-3609, 2008.
- Ungerleider, L.G., Galkin, T.W., Desimone, R., and Gattass, R.:
Cortical connections of area V4 in the macaque.
Cerebral Cortex, 18: 477-499, 2008.
- Mukai, I., Kim, D., Fukunaga, M., Japee, S., Marrett, S., and Ungerleider, L.G.:
Activations in visual and attention-related areas predict and correlate with the degree of perceptual learning.
J. Neurosci., 27: 11401-11411, 2007.
- Rossi, A.F., Bichot, N.P., Desimone, R., and Ungerleider, L.G.:
Top-down attentional deficits in macaques with lesions of lateral prefrontal cortex.
J. Neurosci., 27: 11306-11314, 2007.
- Heekeren, H.R., Marrett, S., Ruff, D.A., Bandettini, P.A., and Ungerleider, L.G.:
Involvement of left dorsolateral prefrontal cortex in perceptual decision-making is independent of response modality.
Proc. Natl. Acad. Sci., USA 103: 1023-1028, 2006.
|
Address:
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Dr.
Leslie G. Ungerleider
Laboratory of Brain and Cognition, NIMH, LBC
Building 10, Room 4C104
10 Center Drive, MSC 1366
Bethesda, MD 20892-1366 |
| Phone: |
301-435-4932 |
| Email Dr. Ungerleider |
| Fax: |
301-402-0921 |
| Lab Web Site: |
http://lbc.nimh.nih.gov/ |
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