Laboratory of Vertebrate Functional Brain Mapping

Our laboratory’s research centers around the brain imaging of animal behaviors as they occur in the nontethered, nonrestrained animal. This emphasis is part of a broader interest in the characterization of the neurobiology, behavior and physiologic function of specific animal models of human behavior and mental illness.

A central dilemma in functional neuroimaging of animal behaviors has been the fact that conventional neuroimaging protocols using positron emission tomography (PET), single photon emission computer tomography (SPECT) and functional magnetic resonance imaging (fMRI) generally rely on immobilization of the subject, which extinguishes all but the simplest activity and introduces the additional variables of restraint stress. The result is that brain function of core mammalian behaviors such as aggression, mating, foraging and social interaction all requiring locomotion — remains poorly understood. In our previous work, we have designed and validated the use of an implantable, miniature, infusion pump (MIP) for the administration of radiotracers in freely moving animals. Current lab projects focus on: (a) applications of the MIP in rats that allow functional brain mapping of complex behaviors using autoradiography, (b) study of the MIP in combination with novel radiotracers to allow an expanded use of PET for functional neuroimaging applications in freely-moving animals, (c) the miniaturization of the MIP for use in mice.

Complementary to the focus on functional brain mapping, is our work concerning the characterization of the neurobiology, behavior and physiologic function of specific animal models of human behavior and mental illness. Past work has included two different cholinergic deafferentation model of dementia in rats, mice deficient in monoamine oxidase which show varying amounts of aggression and anxiety depending on which of two of the isoform of the enzyme is lacking. Current work focuses on a rat model of Parkinson’s disease, visceral pain and the conditioned fear model of anxiety.

A final focus is in the area of technology development. An area of active work is the development of methods for the analysis of brain mapping data obtained from rodents. Another concerns a method for measuring cardiac output by dye dilution and transcutaneous fluorescence – a technique applicable for use in humans, as well as small animals.