'Superstition' in the pigeon
As is well known, an animal's behaviour can be reinforced using food as a reward. This experiment used hungry pigeons, and presented food at pre-determined intervals, with no regard for the bird's behaviour (i.e. no movements, button-pressing or the like affected presentation of food). What is novel in the findings is that the behaviour of the bird before presentation of food was found to be reinforced regardless of it being unrelated to reward. The birds began by turning their heads, then turning their whole bodies, the hopping a step or two to one side. Of course, this behaviour was displayed several times without reward, resulting in some extinction of the behaviour, but overall, periodic reinforcement was enough to maintain and strengthen the response. Skinner likens this to superstitions in humans:
"There are many analogies in human behavior. Rituals for changing one's luck at cards are good examples. A few accidental connections between a ritual and favorable consequences suffice to set up and maintain the behavior in spite of many unreinforced instances. The bowler who has released a ball down the alley but continues to behave as if he were controlling it by twisting and turning his arm and shoulder is another case in point. These behaviors have, of course, no real effect upon one's luck or upon a ball half way down an alley, just as in the present case the food would appear as often if the pigeon did nothing -- or, more strictly speaking, did something else."
B.F. Skinner (1904-1990) was the primary expert in the study of operant conditioning, and this study became one of his best-known pieces of work.
Skinner, B.F. (1948). 'Superstition' in the pigeon. Journal of Experimental Psychology, 38, 168-72.
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