Animals were treated with exogenous ethanol for 10 minutes, two-minute digital movies were recorded, and speed was determined by ImagePro image analysis software. A % relative speed was calculated by dividing treated speed by untreated speed, to account for any baseline speed differences. In each case, the alh knockdown strain was compared to N2 animals tested on the same plates. (a) Knockdown of either alh-6 or alh-13 conferred hypersensitivity to the effects of ethanol on locomotion (*, P < 0.05). (b, c) Knockdown of neither alh-6 nor alh-13 in the background of sodh-1(ok2799) was able to enhance the ethanol sensitivity beyond that of sodh-1(ok2799) alone.