To the Editor.—
Dr Salcman (Arch Neurol 33:215, 1976) commented on our article (Arch Neurol 32:98, 1975) describing the response of enzymes important to brain metabolism after electrode implantation and electrical current application in the hippocampus. He suggested that the electrical measurements were too low and that techniques were inadequately described to enable workers to approach the problem from a different perspective.The electrical current levels reported were similar to those used by others.1.2 The current selected was routinely capable of polarizing the hippocampus, which is well known to have a low electrical threshold; similarly, the auditory nerve and cochlea are also known to have a low electrical threshold.3.4 Procedures of this hippocampal study were not intended to be translatable to the cortex or cerebellum. For such studies, a different species, method, and experimental technique are clearly desirable. It is an enigma that Dr Salcman's calculations were in