Fig. 2. (A) Effects of mutants and drug treatment on the duration of swimming (left) and quiescent (right) bouts. Data were collected starting with the first quiescent bout after the long initial swim, when the worm has entered the episodic phase of swimming. Panels 2–6: decreased GABA [unc-25(sa94ts)] and increased ACh [aldicarb, ace-1(g72);ace-2(p1000), dgk-1(nu62)] decrease swimming and increase quiescence. Panel 7: Mutation in egl-4 decreases the duration of both swimming and quiescent bouts. (B) Fraction of worms in quiescence. Left panel: in the presence of the acetylcholine esterase inhibitor aldicarb, quiescent bouts become progressively longer with time, resulting in an increasing fraction of worms in quiescence. Green, no drug; blue, 0.001 mol l^–1 aldicarb; black, 0.01 mol l^–1 aldicarb; yellow, 0.1 mol l^–1 aldicarb. Right panel: worms lacking command interneurons cycle between swimming and quiescence immediately upon transfer into liquid, have increased quiescence, and remain sensitive to aldicarb. Yellow, glr-1::ICE, buffer; red, glr-1::ICE, 0.001 mol l^–1 aldicarb; wild-type controls (green, blue) same as left panel.