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<fig id="fig3">
<label>3</label>
<caption>
<title>The agent learns to make responses that lead to rewards.
Black line: response leads to reward; gray line: response does
not lead to reward. A color version of this figure is available
on the Web at <inline-supplementary-material
xlink:href="http://dx.doi.org/10.1037/0278-7393.33.2.459.supp">
http://dx.doi.org/10.1037/0278-7393.33.2.459.supp
</inline-supplementary-material></title>
</caption>
</fig>
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link3.ent