What's Worth It?

From deciding to stop hitting “snooze” and get out of bed in the morning to switching of the TV and hitting the hay at night, the mind weighs the costs against the benefits of every choice we make.

A new study by Emory psychologists, published in Proceedings of the National Academy of Sciences, reveals the mechanics of how the brain makes such effortful decisions, calculating whether it is worth expending effort in exchange for potential rewards.

“We showed that the brain’s ventromedial prefrontal cortex (vmPFC), which was not previously thought to play a key role in effort-based choices, actually appears to be strongly involved in the formation of expectations underlying those choices,” says psychologist and senior author Michael Treadway.

Treadway’s lab focuses on understanding the molecular and circuit-level mechanisms of psychiatric symptoms related to mood, anxiety, and decision-making.

“Understanding how the brain works normally when deciding to expend effort provides a way to pinpoint what’s going on in disorders where motivation is reduced, such as depression and schizophrenia,” he says.

The design of the study allowed the researchers to tease apart the effects of recent choices on the formation of value expectations for future decisions. The results revealed a clear role for the vmPFC in encoding an expected reward before all information had been revealed.