David LaBerge (949)-824-7434 dlaberge@uci.edu

We are exploring new experimental procedures, using response-time measures, aimed at manipulating and measuring the intensity of attention in cognitive tasks. Our context for designing response-time experiments is the known brain architecture concerned with attention and cognitive processing in general. Brain imaging experiments have shown that when we process different things (e.g., perceptions, categorizations, motor plans, etc.), different regions of the cerebral cortex become active, and attention can increase these activities to high levels of intensity. Our PET experiments show that, as a visual-shape task demands more attention, the thalamus (located at the brain's center) simultaneously increases its activity along with posterior cortical shape regions known to be involved in the perception of visual shape and with anterior cortical regions known to be involved in voluntary control. It is also known that output fibers of the thalamus activate specific clusters of neurons in every area of cortex, and our simulations of thalamocortical circuitry show that thalamic output fibers have the ability to amplify neural activity in the target region of that output. We are continuing our brain imaging experiments on thalamic emphasis of cortical processing at the UCI Functional Magnetic Resonance Imaging Laboratory.

Ph.D. Stanford University, 1955 (Psychology). Consulting Editor: Memory and Cognition, Pyschomusicology; Fellow: American Psychological Society, AAAS, Society of Experimental Psychologists.

Selected Publications

LaBerge, D. 1995. Attentional Processing: The Brain's Art of Mindfulness. Cambridge, MA: Harvard University Press.

LaBerge, D., Carter, M., and Brown V. 1992. A network simulation of thalamic circuit operations in selective attention. Neural Computation, 4, 318-331.

LaBerge, Carlson, R., Williams, J. and Bunney, B. 1997. Shifting attention in visual space: Tests of moving spotlight models versus an activity distribution model. (in press) Journal of Experimental Psychology: Human Perception and Performance, 17, 65-76.

LaBerge, D. 1990. Thalamic and cortical mechanisms of attention suggested by recent positron tomographic experiments. Journal of Cognitive Neuroscience, 2, 358-372.

LaBerge, D. and Buchsbaum, M. 1990. Positron emission tomographic measurements of pulvinar activity during and attention task. Journal of Neuroscience, 10, 613-619.