ABSTRACT
Optical methods have been used to study various aspects of nervous system function. Early studies focused on the endogenous, optically active elements of the mitochondrial respiratory chain that were measured spectrophotometrically or fluorometrically. Optical measurements of these respiratory chain components provided essentially an on-line indication of oxidative metabolic processes in functioning brain tissue. For the most part, optical studies of brain slices rely on scattering, absorptive, or fluorescence measurements of either intrinsic or exogenously applied indicators. In general, minimal modifications of standard recording chambers are required for optical studies in brain slices. Brain slice preparations are no exception; they have provided a necessary bridge between single-cell and intact brain electrophysiology, as well as being valuable preparations for evaluating neural function with optical tools. Optical signals in brain slices associated with neuronal activation also have been attributed to changes in light scattering.
