The invention relates to a multielectrode probe having a silicon substrate which supports multiple conductive electrodes for deep-brain electrical stimulation or recording of neural responses. The substrate has an upper end with multiple conductive portions for bonding to lead wires, and an elongated shank extends from the upper end. The shank supports multiple spaced-apart electrodes, typically ten in number, and conductive traces electrically connect the electrodes and conductive traces. Multiple probes are combined, and supported as an array by a cylindrical alignment cylinder.