Basic Principles

Abstract

We may start off our discussion of instrumentation by recalling two facts. First, in electrophysiological techniques the standard laboratory approach is to detect and measure bioelectrical potentials, and second, by far the majority of bio-electrical potentials are so small that sensitive apparatus is required to detect and measure them. In addition, we may add that electrophysiology includes the investigation of how living tissues react to electrical currents. We have now standardized some of our knowledge on the applications of such currents; consequently electrical stimulators are available for investigations with electrically active tissues. Finally, we should remember that our living systems are essentially watery saline systems that, through a variety of electrodes, are coupled to physical instruments. Briefly, then, the components of our instrumentation will include electrodes, amplifiers, read-out devices, and stimulators. These components are discussed in the next section.