Ex-4 treatment resulted in a hypoactive phenotype during probe testing. Control males ambulated more than Ex-4-treated males in the easy (a; t(10)=1.925, p=0.0831) and difficult (b; t(9)=2.079, p=0.0677) probes, although these did not reach the level of significance. Females administered Ex-4 moved significantly less than saline-treated females in both the easy (c; t(18)=4.292, p<0.001) and difficult (d; t(17)=4.878, p<0.001) probe trials. † p<0.1; *** p<0.001