Lucy L. Brown

The laboratory studies the functional neuroanatomy of the mammalian basal ganglia. Our goal is to understand the functions of the caudate-putamen, especially the mu opioid receptor-rich zones called striosomes. The basal ganglia integrate information from the entire cortex and have an executive, decision-making function for cognitive and emotional events as well as for movement. The major questions for the lab have been, "How are the basal ganglia anatomically organized to integrate afferents that decide to move?" Also, "What is the functional unit of the caudate-putamen?" We use anterograde tracing techniques, immunocytochemistry, in vitro autoradiography, deoxyglucose autoradiography and functional MRI to address these questions.

We also look at the pathology of the basal ganglia, and we are now investigating mouse models of Huntington's disease. We have found that the lattice-like structure of the mu opioid receptor-rich cell clusters is altered, and the volume and/or number of the striosomes is unexpectedly increased. We are following up this finding by looking at neurogenesis in the striatum of Huntington's mouse models. In addition, we are looking at the behavior of mice with the Huntington mutation and an increase in striosomes.

These are 3D reconstructions through 300 microns of opiate receptor-rich striosomes in the right striatum of mice. The one on the left is from a wild-type mouse and the one on the right is from a mutant model of Huntington's disease. There is a small reduction in striosome area in the mutant, and a redistribution of the striosomes.

Selected Publications