The ability of efficiently acquiring sensory information and selecting an appropriate action is the essence of flexible behaviors. To make good decisions, it is also crucial to evaluate the consequences of previous actions (gains and costs) and adjust strategies for future decisions. Our laboratory is interested in neuronal processes by which sensory information and memory about previous experiences guide behavior of the animal. Our main questions are:

1. How is odor information coded and processed by an ensemble of neurons?
2. What kinds of circuit dynamics underlie decision-making processes?
3. What are the mechanisms for learning based on rewards and punishments?

We have developed an odor-guided perceptual decision task in rats and mice. This behavioral paradigm was recently combined with a multi-electrode recording technique (tetrodes) which allows us to monitor activity of multiple neurons simultaneously while animals are performing a behavioral task. Particular emphasis will be made on the use of behavior. First, behavioral paradigms specify computations (e.g. extracting relevant information in the sensory stimulus) and behavioral goals (e.g. maximizing rewards in a certain period) to be achieved. This in turn guides the way neuronal activities are analyzed. Furthermore, behavioral experiments are necessary to test relevance of certain activity of neurons or hypothesis about "neural codes" obtained in neuronal recordings. We will use various molecular and genetic tools available in mice to further test specific hypotheses experimentally. By combining the above approaches, we wish to establish a causal link between activity of specific neuronal circuits and the dynamics of behavior and learning.

Selected Publications:

Feierstein, C. E., Quirk, M. C., Uchida, N., Sosulski, D. L. and Mainen, Z. F. (2006) Representation of spatial goals in rat orbitofrontal cortex. Neuron, Aug 17;51(4):495-507.

Gurden, H., Uchida, N. and Mainen, Z. F. (2006) Sensory-evoked intrinsic optical signals in the olfactory bulb are coupled to glutamate release and uptake. Neuron, Oct 19;52(2):335-45.

Uchida, N., Kepecs, A., and Mainen, Z. F. (2006) Seeing at a glance, smelling in a whiff: rapid forms of perceptual decision-making. Nature Rev. Neurosci,. 7:485-491.

Uchida, N., and Mainen, Z. F. (2003) Speed and accuracy of olfactory discrimination in the rat. Nature Neurosci. 6: 1224-1229.

Uchida, N., Takahashi, Y.K., Tanifuji, M. and Mori, K. (2000) Odor maps in the mammalian olfactory bulb: domain organization and odorant structural features. Nature Neurosci. 3: 1035-1043.

Uchida, N., Honjo, Y., Jones, K. Weelock, M.J. and Takeichi, M. (1996) Cadherin/catenin-adhesion system is localized in synaptic junctions, bordering the transmitter release zones. J. Cell Biol. 135, 767-779.