The brain uses a different process to make hasty decisions compared to reasoned ones, a new study has found.

Previous studies have identified the trade off the brain must make between speed and accuracy but have concluded it uses the same basic method to make deliberate and rapid decisions.

However, a new study from Vanderbilt University suggests it uses a different mode when making the different decisions, the Daily Mail reported.

The team measured the activity of individual neurons in monkeys which were taught to switch back and forth between fast and accurate decision making using a task that involved picking out a target from an array of objects on a computer screen.

In one experimental condition, monkeys learned that only accurate responses would be rewarded.

In another, they learned that making some mistakes was okay, as long as the decisions were fast.

The signals from single neurons in their prefrontal cortex – the area in the brain dedicated to higher cognition – were monitored.

“Our tests are like two different game shows. One – call it Fast Fury – is like Jeopardy. In order to answer a question you must be the first to hit the buzzer,” lead researcher Professor Richard Heitz, said.

“Buzzing in and answering incorrectly is bad, but being slower than the other contestant means you will never earn a reward,” Heitz added.

“That is much different than the second game show – call it High Stakes Showdown – where buzzing in at any time gives you the opportunity to answer a question, but being wrong results in a serious penalty,” Heitz said.

“The first thing you see is that neural activity of the player of Fast Fury jumps up even before the question is read.

The subjective experience of getting ready that we all experience appears to be reflected in the background activity of neurons in prefrontal cortex,” Heitz said.

In comparison, the neural activity drops to extremely low levels during High Stakes Showdown while the player waits to hit the buzzer.

This picture differs substantially with the standing theory that the brain uses the same process for all types of decisions.

If the contestants in the two game shows were given identical questions the activity of the prefrontal cortex neurons would increases while observers decide how to respond.

But, the new data suggests that this activity is amplified during Fast Fury and suppressed during High Stakes Showdown — meaning the information is analysed differently.

“What this means is that identical information presented to the brain is analysed differently under speed stress than under accuracy stress,” Professor Jeffrey Schall said.

The study was published in the journal Neuron.

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