An implantable electrode arrangement for space-selective detection of neuronal electrical signals propagating along at least one nerve fiber contained in a nerve bundle and selective electrical stimulation of at least one nerve fiber is disclosed, 1. A biocompatible carrier substrate (1) having at least one carrier substrate that can be installed around the bundle and having a straight cylindrical carrier substrate surface (1 ') oriented in a grafted orientation toward the development bundle, and a first (2), said carrier substrate surface having a range oriented in the axial direction (a) and the circumferential direction (U) and having at least two first electrode surfaces (4) arranged in the circumferential direction , Comprising at least three first electrode structures (3) provided in the axial direction and at least two first electrode strips (5) spaced apart from each other in the axial direction, If extension in the circumferential direction and each takes the form ring, the first electrode strip is wrapped around the at least three electrodes structures on both surfaces in the axial direction, and is connected or can be connected to the signal detector and the generator (6). The present invention is distinguished by the fact that at least one second electrode arrangement (7) is arranged next to the first electrode arrangement (2) in axial order on a straight cylindrical carrier substrate facing the nerve bundle, The electrode arrangement At least two second electrode strips (8) axially spaced from one another and extending in the circumferential direction (U) and in each case taking the shape of a ring, and At least one second electrode structure (5) extending in the axial direction between at least two second electrode strips (8) each comprising at least two second electrode surfaces arranged equally distributed in the circumferential direction (U) 13) The second electrode arrangement 7 is connected to at least the signal generator 6 or to an additional si
