Columbia) on an Olympus SZX-7 microscope. Movies were analyzed using ImagePro Plus (6.2) (MediaCybernetics, Rockville, MD) software. We derived two measures of ethanol response, Initial Sensitivity (depression of speed of locomotion at 10 minutes exposure compared to the same strain untreated) and Acute Functional Tolerance (AFT, increase in speed at 30 minutes exposure compared to the same strain at 10 minutes).