FIGURE 4.

Neuronal activation distribution around electrode tracks. (A) Mean ± SD of c-fos expressing neurons within concentric circles in 25 μm radius increments surrounding implanted and stimulated macroelectrode (macro; blue squares, n = 4), sonicoplated microelectrode (sonico micro; red circles, n = 4) and microelectrode electrodes (micro; green triangles, n = 4). *P < 0.05 between macroelectrode, sonicoplated microelectrode, and unplated microelectrode (where data is present). ⁺P < 0.05 between sonicoplated and unplated microelectrode. (B) Mean ± SD neuronal activation density (number of c-fos+/NeuN+ cells/m³) with macroelectrode (macro), sonicoplated microelectrode (sonico micro) and microelectrode (micro) stimulation around the electrode tracks; *P < 0.05 between macroelectrode and sonicoplated microelectrode; ⁺P < 0.05 between sonicoplated and unplated microelectrode; P < 0.05 between unplated microelectrode and macroelectrode.