Matching-to-sample and oddity-from-sample in goldfish.
Goldfish can learn both matching and oddity tasks, giving a simple animal model for conditional-discrimination training.
01Research in Context
What this study did
The team taught goldfish two conditional tasks.
In matching-to-sample, the fish had to touch the color that matched the sample.
In oddity-from-sample, they touched the color that was different.
Three colors were shown at once and the fish used their mouths to respond.
What they found
The fish learned both tasks.
Final scores reached about 75 percent correct.
Some fish topped 85 percent.
Daily curves showed steady improvement and clear color likes and dislikes.
How this fits with other research
Bradshaw et al. (1978) set up the basic trial method one year earlier.
Yelton (1979) ran matching-to-sample with pigeons the same year and found accuracy drops at very small or very large fixed ratios.
Gettinger (1993) later showed a chimpanzee could do matching plus exclusion, proving symmetry-like control in a species closer to humans.
Together the four papers trace a line: first build the procedure, then show it works in fish, tune the schedule, and finally test higher-order relations.
Why it matters
If goldfish can master two opposite rules, your learners probably can too.
Use the simple three-choice setup when you need a quick conditional-discrimination baseline.
Watch for color bias first so you can counterbalance stimuli.
The 75 percent mastery level is a realistic first goal before you move to more complex equivalence tasks.
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02At a glance
03Original abstract
Acquisition of three-alternative simultaneous matching-to-sample and oddity-from-sample was investigated. Five goldfish were trained on matching and five on oddity for a minimum of 70 days. Subsequently, six of the fish were trained for 70 days on the other task. Acquisition was similar for oddity and matching. Correct responding started at about chance level and slowly increased to about 75%, with some animals performing at levels of over 85%. Acquisition of oddity following matching and matching following oddity began below chance. Maximal level of performance on second-task oddity was comparable to that on first-task matching. By contrast, the maximal levels of performance when matching was the second task were not as high as that of the same subjects at the end of first-task oddity. All fish exhibited strong color preferences during matching acquisition but not during oddity acquisition. The data demonstrated that goldfish can acquire a discrimination in which the stimulus associated with reinforcement depends on the identity of a second stimulus.
Journal of the experimental analysis of behavior, 1979 · doi:10.1901/jeab.1979.31-259