The ornamental design for an apparatus for stimulation of the nervous system, as shown and described.
FIG. 1 is a perspective view of an apparatus for stimulation of the nervous system in accordance with my new design;
FIG. 2 is a front elevational view of the apparatus for stimulation of the nervous system shown in FIG. 1, the rear, left side and right side views being the same; and,
FIG. 3 is a top plan view of the apparatus for stimulation of the nervous system shown in FIG. 1, the bottom plan view being the same.
The broken lines shown in the drawings represent portions of the apparatus for stimulation of the nervous system that form no part of the claimed design.