The capacities of three different conditioned stimulus modalities (lig
ht, noise, and airflow produced by a fan) to produce fear-potentiated
startle were evaluated. Previous experiments have shown that following
either light-shock or noise-shock pairings, both the Light and noise
conditioned stimuli acquire the ability to potentiate the acoustically
elicited startle response in rats (the so-called fear-potentiated sta
rtle effect). In Experiment 1, the ability of airflow produced by a fa
n to act as a conditioned stimulus was investigated. Rats were given e
ither paired or unpaired fan-shock training followed by a test for fea
r-potentiated startle. The fan conditioned stimulus potentiated startl
e only in the group given explicit fan-shock pairings. In Experiment 2
, we evaluated the discriminability of the three conditioned stimulus
modalities. Rats were given light, noise, or fan-shock pairings and we
re subsequently tested for fear-potentiated startle with the trained c
onditioned stimulus as well as the two remaining novel conditioned sti
muli. Only the trained conditioned stimulus potentiated startle. These
results show that fear-potentiated startle can be produced with three
discriminable conditioned stimulus modalities, allowing the future us
e of fear-potentiated startle in the investigation of higher order con
ditioning phenomena.