In little less than a decade brain slices have gained prominence among neurobiologists as appropriate tools to study cellular electrophysiolog­ ical aspects of mammalian brain function. The purpose of this volume is to present in some detail several inquiries in the brain sciences that have benefited greatly by the use of brain slices. The book is directed primarily toward advanced students and researchers wishing to evaluate the impact these in vitro preparations of the mammalian brain are having on neurobiology. The term brain slice has come to refer to thin (100-700 j. Lm) sections of a brain region prepared from adult mammals and maintained for many hours in vitro, for either electrophysiological or biochemical stud­ ies. In addition to good accessibility, slices feature relatively intact syn­ aptic connections that allow a variety of experiments not feasible with standard in vivo or tissue culture preparations. Certain electrophysiol­ ogical studies once practical only with invertebrate models are becoming routine with mammalian brain slices. The ability to perform both bio­ chemical and electro physiological experiments on the same piece of CNS tissue provides additional bright prospects for future research. Although most of the electrophysiological studies have dealt with hippocampal slices, it should be evident from this book that slice methodology is not limited to the hippocampus. The Appendix, "Brain Slice Methods," is a multiauthored treatment of the technical aspects of brain slice work, collected into one document.