Implanted Electrodes for Stimulating or Recording from Deep-Lying Brain Structures.

Abstract

By a simple extension of the stereotaxic technic, and by using materials which are durable and non-irritating, a system has been devised which allows accurate, permanent placement of several monopolar electrodes throughout a wide region of the upper brain stem in cats. A flat plastic plate is attached to the cranium with stainless steel screws and leveled until it is parallel with and 24 mm. above the original Horsley-Clarke horizontal reference plane. Another plastic plate carrying 6 monopolar insulated nicrome wire electrodes pre-set to reach the desired depths and distances from the midline is then positioned with the stereotaxic instrument and cemented permanently to the base plate with rapid drying plastic cement. The leads are identified and taken out through stab wounds in the skin at the back of the head. Such electrodes remain serviceable for months and are tolerated quite well by the animals.