Robert is a veteran of the war in afghanistan. he suffers from posttraumatic stress disorder (ptsd). now, back home in a quiet kansas neighborhood, he jumps when he hears a firecracker or a car backfire. in the terminology of classical conditioning, these sounds are best thought of as stimuli.

In the terminology of classical conditioning, these sounds best thought of as a conditioned stimuli. In which a conditioned stimuli occurs when an unconditioned stimulus has been linked or affected the neutral stimulus that will likely trigger an affect that makes the conditioned response to appear.