A microelectrode positioning system for semiautomatically tracking neuronal spikes

The authors proposed here a novel microelectrode positioning system for tracking neuronal spikes of a target neuron by countermoving the microelectrode manipulator against the uncontrollable movement of the microelectrode and/or brain tissue. The position of a microelectrode is adjusted semiautomatically by a computer-controlled micromanipulator so that the mean amplitude of spikes generated by a target neuron is maximized. In an preliminary experiment in which the computer-controlled microelectrode holder was moved manually by another micromanipulator, the initial movement of the manual micromanipulator was counterbalanced by the movement of the computer-controlled micromanipulator. Thus the system succeeded in tracking neuronal spikes of the same target neuron. The authors' system seems useful in long-term recording of neuronal activity, particularly in situations where microelectrode-neuron distance is unstable.