"Bioelectricity is about the electrical phenomena of life processes, and is a parallel to the medical subject electrophysiology. One basic mechanism is the energy consuming cell membrane ion pumps polarising a cell, and the action potential generated if the cell is excited and ion channels open. The dipolarisation process generates current flow also in the extracellular volume, which again results in measurable biopotential differences in the tissue. An important part of the subject is intracellular and extracellular single cell measurements with microelecroeds. Single neuron activity and signal transmission can be studied by recording potentials with multiple microelectrode arrays. In addition to measure on endogenic sources, bioelectricty also comprises the use of active stimulating current carrying (CC) electrodes. Since bioelectricity is about life processes the experiments are per definition in vivo or ex vivo."