AbstractRats were exposed to two procedures which enabled them to press a lever to turn off a 90 or 100 kV/m 60‐Hz electric field or, later in the study, illumination from an incandescent lamp. Under one procedure, a response turned off the stimulus for a fixed duration, after which the stimulus was turned on again. A response during the off‐period restarted the fixed duration. None of the rats turned the field off reliably. Next, under an alternative procedure, pressing one lever turned the field off; pressing the other lever turned it back on; responding under those conditions differed little from that seen at 0 kV/m. Under both procedures, when illumination from an incandescent lamp served as the stimulus, each rat did turn the stimulus off, and performances varied with stimulus intensity. The results show that a 100 kV/m 60‐Hz electric field is not sufficient to function as an aversive stimulus under two procedures where illumination from a lamp does function as an aversive sti