Research Interests

I am interested in the mechanisms that underlie perception. Mammals perceive thousands of environmental chemicals as having odors or tastes. We identified four different types of receptors that recognize odors, pheromones, and bitter and sweet tastes, respectively, explaining how chemicals are initially detected in peripheral sense organs. We found that 1000 different odor receptors are used combinatorially to detect different odors and encode their identities, much like letters of the alphabet are used to form different words. The odor stimulus is deconstructed into a series of features, each encoded by a different receptor. To learn how these deconstructed features generate perceptions, we examined how odor receptor inputs are organized as signals travel from the nose to the olfactory bulb of the brain and then the olfactory cortex. These studies revealed that signals from different receptors are segregated in both the nose and olfactory bulb. However, different receptor inputs are randomly interspersed in the nose whereas the olfactory bulb has a stereotyped map, identical among individuals, in which information from each receptor is mapped onto two specific sites. In the olfactory cortex, there is again a stereotyped map of receptor inputs, but it is unrelated to the bulb map. Here, different receptor inputs overlap extensively and single neurons receive combinatorial receptor inputs. The stereotyped maps in the bulb and cortex assure that the neural codes for odors remain constant over time, explaining how odor chemicals can elicit memories and generate similar perceptions in different individuals. The integration of different receptor inputs in single cortical neurons is likely to represent an initial step in the reconstruction of the deconstructed features of odor stimuli to generate diverse odor perceptions.

Membership Type

Member

Election Year

2003

Primary Section

Section 24: Cellular and Molecular Neuroscience

Secondary Section

Section 28: Systems Neuroscience