What actually happens in your brain when you change your mind?

Imagine a game show where the host asks the contestant to randomly pick one option out of three: A, B or C.

After the contestant chooses, say, option B, the host reveals one of the remaining choices (say C) does not contain the prize. In the final step, the contestant is asked whether they want to change their mind and select the remaining option A or stick with their original choice, B.

Dubbed the Monty Hall problem after an American game show host, this famous puzzle has entertained mathematicians for decades. But it can also tell us something about how the human mind and brain function.

Why do some people choose to change their minds while others stick with their first choice? What would you do and what might your choice reveal about your mind?

Choosing when to change

Research on changes of mind uses the concept of “metacognition” to explain when and how mind changes occur. Broadly speaking, metacognition refers to psychological and biological processes that inform us about how well we are doing the task.

In a sense, metacognition is that inner voice telling us we are either on track or that we should try harder.

Intuitively, changes of mind may be triggered by low confidence in our initial choice. Yet, when my colleagues and I reviewed the research on changes of mind about a range of different kinds of decisions, we found many studies showing people change their minds less often than you might think. This was surprising, given how often we feel uncertain about our choices.

On the other hand, when people do choose to change their mind, it is often for the better. This ability to accurately gauge whether to change your mind is referred to as metacognitive sensitivity.

Our research has found people often make better decisions about whether to change their minds when they are put under time pressure.

Understanding more about how we decide to change our minds may lead to ways to train our minds to make better choices.

Our brains show when we will change our minds

Another interesting question about changes of mind is when do people choose to change their minds. The answer to this question might seem obvious, as people can change their minds only after they have made the first choice.

To find out more about this process, we measured people’s brain activity before they even made their initial choice in a laboratory task that involved answering questions about moving images on a screen. We successfully predicted changes of mind seconds before they took place.

These findings suggest brain activity that predicts changes of mind could be harnessed to improve the quality of the initial choices, without needing a change of mind later. Training based on this brain activity may help people in sensitive professions such as health or defence make better choices.

Why don’t we change our minds more often?

Research on metacognition has provided robust evidence that changes of mind tend to improve choice outcomes. So why are people so reluctant to change their minds?

There are at least two possible reasons. First, deciding to change your mind is typically a result of making extra cognitive effort to analyse the quality of the initial choices. Not every decision requires that effort, and most everyday choices can be good enough rather than perfect.

For example, choosing a wrong brand of orange-flavoured soft drink will probably not significantly impact our wellbeing. In fact, consumer research shows buyers tend to report higher product satisfaction when offered fewer choices, a phenomenon called “the paradox of choice”. This suggests having more choices and, therefore, greater opportunity to change one’s mind may be more cognitively effortful.

Second, frequent changes of mind may signal personality traits that are not socially desirable. Meaningful and fulfilling interpersonal relationships rely on the ability to predict and rely on another person’s actions.

Erratic and frequent changes of mind could negatively impact relationships and people may avoid doing this to improve their social integration.

The future of changing your mind

The science of changes of mind is an exciting field of research, developing at a fast pace.

Future developments in the field might focus on identifying specific brain activity markers of subsequent correct changes of mind. If reliable and valid markers are found, they could be harnessed to help people become experts on when they should change their minds to achieve better professional and social outcomes.

Oh, and coming back to the Monty Hall problem: if you ever do find yourself offered this choice by a game show host, you should definitely change your mind. In this scenario, for mathematical reasons, switching away from your first pick will double your chances of winning.