A concentrically and radially adjustable holder for ten microelectrodes

A device is described that allows to make simultaneous recordings with ten microelectrodes or ten very small extracellular electrodes. The ten electrode holders are mounted in a circle. The diameter of the circle can be varied with an accuracy of 0.1 mm. At the same time the position of the electrodes can be changed radially over an angle of 36 degrees with an accuracy of 1 degree. This device can be very valuable for instance to map the spread of activation in a cardiac preparation.