Exposure to ether induced c-fos in the STN, GP, EPN and SNr.
STN inhibition with muscimol suppressed ether-evoked c-fos expression in the GP, EPN and SNr.
STN-HFS increased c-fos expression in GP, EPN and SNr above that induced by ether alone.
Kainic acid injection and HFS in the STN induced c-fos expression in the GP, EPN and SNr.
STN-HFS excites rather than inhibits efferent target structures.