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Published on: May 3, 2012
Observing response acquisition: preference for unpredictable appetitive rewards obtained under conditions predicted
Summary
Rats preferred unpredictable reward cues when rewards were small and immediate, or small and delayed without predictive cues. This behavior supports a mathematical model of appetitive learning.
Area of Science:
- Behavioral Neuroscience
- Animal Behavior
- Learning and Memory
Background:
- Organisms often learn to associate stimuli with outcomes.
- Predictive cues can influence decision-making in reward-seeking behavior.
Purpose of the Study:
- To investigate rat preference between predictable and unpredictable reward situations.
- To identify conditions favoring preference for predictable versus unpredictable reward cues.
Main Methods:
- Five E-maze experiments were conducted with rats.
- Rats chose between predictable (stimuli correlated with reward) and unpredictable (stimuli uncorrelated with reward) situations.
- Reward size, delay, and discrimination difficulty were manipulated.
Main Results:
- Preference for unpredictable situations occurred with small, immediate rewards, or small, delayed rewards without predictive cues during delay.
- Preference for unpredictable situations also occurred with large, immediate rewards under difficult discrimination, or when a nonreward cue was present.
- Preference for predictable situations was strongest with large, delayed rewards or when a reward cue was present.
Conclusions:
- Rat reward-seeking behavior is influenced by reward predictability, size, delay, and discriminative stimuli.
- Findings support the DMOD (Daly modification of the Rescorla-Wagner model) predictions for appetitive learning.
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