A multiple floating microelectrode for chronic implantation and longterm single unit recording in the cat.

This paper describes a multiple electrode, suitable for chronic implantation and single unit recording in the superficial cerebral cortex of the cat. The electrodes are fine wires, 5-8 per implant, not kept together in a bundle; a segment of them floats freely in saline in a closed chamber over the place of penetration. The electrode tips are not sharpened electrolytically, but cut at a bevel during surgery. Longevity of the implants is improved by slowing down the occasional rapid head shaking characteristic of cats, which tends to tear out implanted electrodes, by means of a small weight attached by a bar to the head.