Fig. 5.

HFB stimulation frequencies, intensities, and test pulse widths for selectively activating different groups of smaller axons without activating larger axons: A. 2 μm vs. 5-20 μm; B. 2-5 μm vs. 10-20 μm; C. 2-10 μm vs. 20 μm. The legends in B and C indicate different test pulse widths which apply to all graphs. The stimulation parameters enclosed by thick or dashed lines are suitable for activating the small axons without activating the large axons. The grey or dashed areas indicate the regions where the small axons fire action potentials repetitively.