Daniel Rojas B.S., Pontificia Universidad Catolica de Chile email: dirl at uchicago dot edu Advisor: Leslie Kay

I am interested in how sensory systems are coupled with the activity of the animal as a whole. I favor the approach that views the activity of the 'sensors' and what we call 'perception' as continuously engaged with the animal’s physiological and behavioral states. This view is opposed to that which studies sensory systems segregated from the natural activity of the animal, using arbitrary external stimuli and simplified internal milieu as experimental conditions. To deal with these issues, I study the olfactory system of the rat. Usually, different kinds of odorant molecules reach different zones of the olfactory epithelium, depending on the molecule’s properties and air flow velocity. The net effect is that an odor stream activates the sensory neuron population unevenly. Since different zones in the epithelium are mapped onto distinct regions in the olfactory bulb, the animal could exploit the aforementioned processes to achieve discrimination between different odorants by actively modulating the airflow patterns through sniffing. To experimentally address this idea, I attempt to record both sniffing and relevant neural activity from freely behaving rats during odor discrimination tasks. If the animal does employ active and directed manipulation of airflow patterns (sniffing) to discriminate odorants, this would suggest that the phenomenon of distinguishing odorants relies on sensorimotor loops that engage several physiological systems.

Committee on Neurobiology  |  University of Chicago

03/31/2008