Ulrich, R. E., & Azrin, N. H. (1962).
Reflexive fighting in response to aversive stimulation.
Journal of the Experimental Analysis of Behavior,
5, 511-520.
Reflexive fighting was elicited between paired rats as a reflex
reaction to electric shock prior to any specific conditioning.
Such fighting was fairly stereotyped and easily differentiated
from the rats' usual behavior. The strength of this reflex was
not attributable to any apparent operant reinforcement.
Elicitation of fighting was a direct function of the enclosed
floor area and a nonmonotonic function of the shock intensity.
Failure to scramble the polarity of the electrified grid produced
inconsistent fighting. Under optimal conditions fighting was
consistently elicited by shock regardless of the rat's sex,
strain, previous familiarity with each other, or the number
present during shock. Repeated shock presentations did not
produce an appreciable decrease in fighting until signs of
physical debility appeared. Although shock did not cause a rat to
attack inanimate objects, it did produce attack movements toward
other small animals. Failure of guinea pigs to defend themselves
revealed that the elicitation of fighting from the rat does not
require reciprocal attack. Paired hamsters showed fighting
reactions similar to those of the rats, whereas guinea pigs
failed to fight. Electrode shock and a heated floor elicited
fighting between the rats, but intense noise and a cooled floor
did not.