In 1912 one of Pavlov’s students,
Eroféeva, published an experiment related to Pavlov’s ideas
on psychopathology. Eroféeva applied mild electric shock
to a dog’s skin preceding food delivery, and found that as
long as the aversive conditioned stimulus (CS) for food was
applied to one part of the dog’s body, defensive behaviors
were eliminated and replaced by a conditioned salivary
response. This effect was termed counter-conditioning, and
it was demonstrated that conditioning methods could
neutralize the effects of aversive stimulation when paired
with an appetitive response. When the shock was later
applied to other parts of the dog’s body not conditioned in
earlier training phases, there was no generalization of the
salivary response, and the established conditioned response
virtually disappeared, leading the animal to become very
excited (Eroféeva