<p>First, the concept of optimality of a learning curve is not well defined. You can measure at least 3 different aspects of learning:</p>

<ol>
<li>Speed of learning</li>
<li>Time before extinction</li>
<li>Performance at peak</li>
</ol>

<p>Of course, there may be other measures as well, and any combination of such measure may also be a legitimate measure for certain uses.</p>

<p><strong>Conditioned Taste Aversion (CTA)</strong> is a form of learning in which animals (and humans) learn to avoid a type of food after consuming it and suffering symptoms resembling food poisoning shortly after. <strong>In certain cases, the learning can take a single trial, cause the animal to completely avoid the food, and last for a lifetime <a href="http://psycnet.apa.org/psycinfo/1998-08099-000"><sup>[1]</sup></a></strong>, making this an optimal learning in all of the above 3 measures. </p>

<p>However, CTA is a very special and specific type of learning, and won't help you in teaching your rat to walk in a maze... <strong>I haven't found a methodological comparison of different types of reinforcements, and I suspect such a comparison might be very difficult or even impossible</strong>, because the efficacy of a (positive) reinforcement is greatly affected by the animal's "appetite" for it: for example, to use food as a reinforcement, rats are usually starved (the technical term is "maintained on a food deprivation schedule") for a few days. To use water as a reinforcement, rats are kept on a water deprivation schedule. How would you equate the subjective level of starvation and thirst? </p>

<p>Other aspects of the learning schedule have been studied more thoroughly. For example, to produce a long lasting learning (increase measure #2) at the expanse of speed of learning (measure #1) and peak performance (#3), you can provide partial reinforcement: reinforce the animal only on some of the trials <a href="http://psycnet.apa.org/journals/bul/47/3/193/"><sup>[2]</sup></a>.</p>

<hr>

<p>[1]  Conditioned taste aversion: Memory of a special kind. Bures, Jan; Bermúdez-Rattoni, Federico; Yamamoto, Takashi; Oxford University Press, 1998  doi: <a href="http://psycnet.apa.org/psycinfo/1998-08099-000">10.1093/acprof:oso/9780198523475.001.0001</a> </p>

<p>[2]  Partial reinforcement: a review and critique. Jenkins, William O.; Stanley Jr., Julian C; Psychological Bulletin, Vol 47(3), May 1950  doi: <a href="http://psycnet.apa.org/journals/bul/47/3/193/">10.1037/h0060772</a></p>

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2012-08-18T20:51:46.323Z
2012-08-18T20:51:46.323Z
Ofri Raviv
<p>When using operant conditioning to train mice or rats, what type of stimulus is most effective? For example, does a negative reinforcement of a loud noise have a more profound effect than a negative reinforcement of pain? What about for positive reinforcement? Is pleasure more powerful than food? Which type of stimulus is considered optimal for learning? </p>

CC BY-SA 3.0
2012-08-18T20:52:54.060Z
related: http://cogsci.stackexchange.com/questions/510/positive-and-negative-reinforcement-and-punishment-effectiveness and http://cogsci.stackexchange.com/questions/1092/does-not-consistently-providing-a-reward-strengthen-operant-conditioning
Ofri Raviv
<learning><animal-cognition><conditioning><behaviorism>
Which type of stimulus results in an optimal learning curve for rats and mice?
Josh
# Which type of stimulus results in an optimal learning curve for rats and mice?

(Asked by: username_0 on 2012-08-17)

When using operant conditioning to train mice or rats, what type of stimulus is most effective? For example, does a negative reinforcement of a loud noise have a more profound effect than a negative reinforcement of pain? What about for positive reinforcement? Is pleasure more powerful than food? Which type of stimulus is considered optimal for learning?

**Tags:** learning, animal-cognition, conditioning, behaviorism

> **Comments:**
> **username_1**: related: http://cogsci.stackexchange.com/questions/510/positive-and-negative-reinforcement-and-punishment-effectiveness and http://cogsci.stackexchange.com/questions/1092/does-not-consistently-providing-a-reward-strengthen-operant-conditioning  

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## 1 answers

### Answer by username_1 on 2012-08-18. Score: 7 | Accepted answer

First, the concept of optimality of a learning curve is not well defined. You can measure at least 3 different aspects of learning:

1. Speed of learning
2. Time before extinction
3. Performance at peak

Of course, there may be other measures as well, and any combination of such measure may also be a legitimate measure for certain uses.

**Conditioned Taste Aversion (CTA)** is a form of learning in which animals (and humans) learn to avoid a type of food after consuming it and suffering symptoms resembling food poisoning shortly after. **In certain cases, the learning can take a single trial, cause the animal to completely avoid the food, and last for a lifetime [[1]](http://psycnet.apa.org/psycinfo/1998-08099-000)**, making this an optimal learning in all of the above 3 measures.

However, CTA is a very special and specific type of learning, and won't help you in teaching your rat to walk in a maze... **I haven't found a methodological comparison of different types of reinforcements, and I suspect such a comparison might be very difficult or even impossible**, because the efficacy of a (positive) reinforcement is greatly affected by the animal's "appetite" for it: for example, to use food as a reinforcement, rats are usually starved (the technical term is "maintained on a food deprivation schedule") for a few days. To use water as a reinforcement, rats are kept on a water deprivation schedule. How would you equate the subjective level of starvation and thirst?

Other aspects of the learning schedule have been studied more thoroughly. For example, to produce a long lasting learning (increase measure #2) at the expanse of speed of learning (measure #1) and peak performance (#3), you can provide partial reinforcement: reinforce the animal only on some of the trials [[2]](http://psycnet.apa.org/journals/bul/47/3/193/).

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[1] Conditioned taste aversion: Memory of a special kind. Bures, Jan; Bermúdez-Rattoni, Federico; Yamamoto, Takashi; Oxford University Press, 1998 doi: [10.1093/acprof:oso/9780198523475.001.0001](http://psycnet.apa.org/psycinfo/1998-08099-000)

[2] Partial reinforcement: a review and critique. Jenkins, William O.; Stanley Jr., Julian C; Psychological Bulletin, Vol 47(3), May 1950 doi: [10.1037/h0060772](http://psycnet.apa.org/journals/bul/47/3/193/)


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