When psychologists talk about rewards and punishments, they generally agree that most people prefer to enjoy rewards—a plate of cookies, watching a movie—as soon as they can and, conversely, will defer punishment—filing taxes, fixing the kitchen sink—for as long as possible. When it comes to physical pain, however, those trends tend to reverse. People seem eager to take on the pain, researchers report in the journal PLoS Computational Biology, in order to get it over and done with.

To investigate this contradiction to the norm, the authors hooked up 33 masochistic volunteers to electric shocks machines, which were connected to the participants’ fingers. The subjects could chose to delay the shocks by distributing them over a 15 minute period, or they could chose to have the shocks administered all at once—but with the price of having more total shocks than if they delayed. The group showed a strong preference for getting the shocks out of the way as quickly as possible, despite the extra punishment they received in doing so.

Next, the authors presented 30 people with a hypothetical future dental appointment, which they were told they could schedule some time between the same day and about eight months into the future. All of the procedures promised to be painful, but at varying degrees of pain randomly distributed among different dates. This time, the results were more varied. Twelve people did not care when their appointment took place, three people wanted it to occur much later and fifteen people wanted to get it over with as soon as possible. On average, though, the group was biased in favor of getting the appointment over and done with—even if that meant taking on a bit more pain.

“In some cases, such as pain, people seem to prefer to expedite punishment, implying that its anticipation carries a cost,” the authors conclude.

Unfortunately, however, that cost on our psyche probably isn’t confined to physical pain. As LiveScience reported last year, for some people, anticipating taking a math test is enough to activate pain networks in their brain.

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