Astrocyte response to implanted electrodes. (a–c) Typical responses, with electrode track denoted, to platinum, P3MT, and PEDOP, respectively. (d) Summary of responses for all animals tested. Number of animals tested: Platinum, n=11, P3MT, n=6, PEDOP, n=7. Standard errors are indicated for each type of electrode. *=significant difference for both Pt vs P3MT and for Pt vs PEDOT. p values are specified in the text. Scale marker in (a)–(c) corresponds to 250 microns.