By Susan Milius
Give lab rats a week at the Rodent Ritz and they’re not thinking Cheerios so much anymore. They’re thinking chocolate.
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Upgrading their real estate changed rats’ bias in guessing what to do about ambiguous cues in a lab test, says cognitive neuroscientist Nichola Brydges of the University of Edinburgh.
A week after moving into a bigger, better furnished cage, rats had grown more likely to take a chance that a confusing signal would lead to a bit of chocolate to eat — an indication of optimism — instead of just half a Cheerio. Rats had been trained that a wrong choice in responding to a cue would mean not getting any reward, so they had an incentive to choose correctly, Brydges and her colleagues report in an upcoming issue of Animal Behaviour.