Peter Singer-Animal Liberation

(BlackTrush) #1

floor. Pairs of rats were given electric shocks until they
learnedtofightbystrikingoutattheotherratwhilefacing
each other in an upright position or by biting. It took an
averageofthirtytrainingtrialsbeforetheratslearnedtodo
this immediately on the first shock. The researchers then
placedtheshock-trainedratsinthecageofuntrainedratsand
recorded their behavior. After one day, all the rats were killed,
shaved, and examined for wounds. The experimenters
concludedthattheir“resultswerenotusefulinunderstanding
the offensive or defensive nature of the shock-induced
response.”^42


At Kenyon College in Ohio, J. Williams and D. Lierle
performedaseriesofthreeexperimentstostudytheeffects
that stress control had on defensive behavior. The first
experimentwasbasedontheassumptionthatuncontrollable
shockenhancesfear.Sixteenratswere placedin plexiglass
tubesandweregiveninescapableelectricshockstotheirtails.
They were then placed as intruders into an
alreadyestablishedcolonyofratsandtheirinteractionswith
theotherswererecorded.Inthesecondexperiment,twenty-
fourratswereabletocontroltheshockthroughtraining.In
the third experiment, thirty-two rats were exposed to
inescapableshockandcontrollableshock.Theexperimenters
concluded:


Although these findings and our theoretical formulations
emphasizetheinterrelationshipsamongshockcontrollability,
the predictability of shock termination, conditioned stress
cues,fear,anddefensivebehavior,furtherexperimentationis
necessary to examine theprecise nature of thesecomplex
interactions.^43

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