Observing stimulus sources that signal food or no food.
Stimuli that signal upcoming food become conditioned reinforcers and sustain observing by themselves.
01Research in Context
What this study did
Researchers worked with pigeons in a small lab. They let the birds peck a key to see colored lights. One light always came before food. Another light never did. A third light gave no hint about food.
The team kept every other factor the same. Food chance, timing, and effort stayed flat. Only the meaning of the light changed.
What they found
The pigeons pecked most to see the food light. They pecked less for the neutral light. They pecked least for the no-food light.
The food-linked light acted like a treat itself. The birds worked just to look at it.
How this fits with other research
Ginsburg et al. (1971) showed the same lab that lights linked to food boost observing. Jenkins et al. (1973) sharpened the point by proving the food cue itself is the reinforcer, not the information.
Thomson (1974) seemed to disagree. That study found pigeons peck most when food odds sit near 50 %. The clash fades once you see C kept uncertainty varied while M held it equal. When uncertainty is fixed, food cues win every time.
Jason et al. (1985) later extended the rule to humans. Adults only watched warning signals if those signals helped them work smarter. The conditioned-reinforcement idea crossed species.
Luckett et al. (2002) repeated the pattern in rats. Animals still favored the stimulus that marked the richer payoff. The core finding travels across birds, people, and rodents.
Why it matters
You can turn neutral cues into mini-reinforcers by pairing them with strong rewards. Use a green card before each preferred break, a red card before lesser tasks. Clients may work to see the green card alone, giving you a cheap way to maintain engagement without extra food or praise. Keep the signal short, consistent, and exclusive to the best reinforcers to protect its value.
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02At a glance
03Original abstract
Pigeons were given a choice between observing a stimulus source that was uncorrelated with food or one that was informative. The informative source was either positive, in which a stimulus change signalled food, or negative, in which change signalled no food. If observing is supported by the reduction of uncertainty, the negative as well as the positive source should be preferred to the uncorrelated source. On the other hand, if observing requires support by conditioned reinforcement, the negative source should not be preferred to the uncorrelated source. Two keys served as stimulus sources in a discrete trial procedure. The keys were lighted together, remained on for a variable length of time, and went off together. A key could change color 1 sec before going off. In the uncorrelated source, the change occurred equally often on trials ending with or without food. In the positive information source, the change occurred only on food trials, whereas in the negative information source, it occurred only on no-food trials. All stimulus changes and food delivery were response independent. As measured by orientation and autoshaped pecking, the positive information source was preferred to the uncorrelated source. However, the uncorrelated source was preferred to the negative information source. The latter result does not support the view that observing behavior is reinforced by the reduction of uncertainty. The positive and negative information sources reduced uncertainty equally but only the positive source provided a signal that could act as a conditioned reinforcer by virtue of its relation to food.
Journal of the experimental analysis of behavior, 1973 · doi:10.1901/jeab.1973.20-197