A method of providing a channel in nervous tissue filled with an aqueous gel for implantation of a microelectrode or other medical device lacking sufficient physical stability for direct implantation by insertion, comprises providing an apparatus comprising an oblong rigid pin covered by a dry gel forming agent； locating a target in the tissue； defining a straight insertion path a desired tissue insertion point and the target； aligning the pin with its end foremost with the insertion path； inserting the pin into the tissue to a position near or at the target； allowing sufficient time to pass for a gel to be formed around the pin, withdrawing the pin. Also disclosed is a corresponding channel； a method of implantation of a microelectrode or microprobe into nervous tissue via the channel； a corresponding method of implantation of living cells； a corresponding apparatus for forming the channel.
