Electrophysiology

Electrophysiology is the study of the electrical properties of biological cells and tissues. It involves measurements of voltage change or electrical current flow on a wide variety of scales from single ion channel proteins, to whole tissues like the heart. In neuroscience, it includes measurements of the electrical activity of neurons, and particularly action potential activity.

Definition and scope

Classical electrophysiologic techniques

Classical electrophysiology involves placing electrodes into various preparations of biologic tissue. The principle types of electrodes are: 1) simple solid conductors, such as discs and needles (singles or arrays), 2) tracings on a printed circuit boards, and 3) hollow tubes filled with an electrolyte, such as glass pippettes. The principal preparations include 1) living organisms, 2) excised tissue (acute or cultured), 3) dissociated cells from excised tissue (acute or cultured), 4) artificially grown cells or tissues, or 5) hybrids of the above.

If an electrode is small enough in diameter (on the order of microns), then the electrophysiologist may choose to insert the tip into a single cell.

Many particular electrophysiological readings have specific names:

• Electrocardiography - for the heart
• Electroencephalography - for the brain
• Electrocorticography - from the cerebral cortex
• Electromyography - for the muscles
• Electrooculography - for the eyes
• Electroretinography - for the retina
• Electroantennography - for the olfactory receptors in arthropods

Other websites

• EP Lab Digest - Trade Publication for EP Professionals Archived 2006-05-10 at the Wayback Machine