Aaron David Redish, Principal Investigator

Electrode Localization Through Reconstruction of Three-dimensional Patch/Matrix Anatomy From Two-dimensional Histological Slices

Striatal dysfunction has been implicated in a number of human diseases, including Parkinson’s disease, Huntingon’s disease, obsessive-compulsive disorder, and Tourette’s syndrome. These researchers are studying the behavioral correlates of striatal cells in rats; that is, they record the firing of striatal neurons and ask what information is carried by those firing patterns. The recording technology consists of twelve individual electrodes, each capable of recording the separate spike trains of three to five cells. The striatum consists of a complex, interdigitated structure called patch and matrix. Although these two “components” consist of similar cell types (thus the recordings look similar from an electrical standpoint), they have very different input and output pathways (thus, they should process very different information). These two compartments are detectable using immunohistochemistry, staining thin-sliced (40 µm) sections for µ-opioid receptors. The researchers can also detect the positions of the electrodes were within these sections. However, they cannot tell which electrode corresponds to which marker.

In order to solve this problem, the researchers are using resources of the Basic Sciences Computing Laboratory to reconstruct the slices into a three-dimensional structure that will allow them to see the paths of all twelve electrodes directly and to see the three-dimensional structure of the patch/matrix. This will allow them to determine the locations recorded by each electrode and to measure the proportion of patch/matrix by each electrode. They will then be able to answer questions about the behavioral correlates of cells within patch and matrix.