Skip to main content

Verified by Psychology Today

Kelly Turner Ph.D.
Kelly Turner Ph.D.

The Science Behind Intuition

Why you should trust your gut.

Almost every Radical Remission cancer survivor I’ve studied used their intuition to help make decisions related to their healing process. Research on intuition and following your ‘gut’ instinct may explain why.

Brain diagram

Scientists have discovered that humans appear to have two, very different “operating systems.” System 1 is our quick, instinctual, and often subconscious way of operating – it is controlled by our right brain and by other parts of our brain that have been around since prehistoric times, known as the “limbic” and reptilian” parts of our brain. System 2 is our slower, more analytical, and conscious way of operating – it is controlled by our left brain and by newer parts of our brain that have only developed since prehistoric times (also known as the “neocortex”). Researchers have found that intuition is part of System 1, which is why it comes on so rapidly and often does not make rational sense to us. In other words, intuitive decisions are not something that we have thought out carefully with reason, but rather choices that have arisen quickly out of instinct.

But why, exactly, should we trust our gut instinct? One reason would be because researchers have found that System 1 often knows the right answer long before System 2 does. For example, in one study, researchers asked their subjects to play a card game where the goal was to win the most money. What the subjects did not realize, however, is that the game was rigged from the start. There were two stacks of cards to choose from; one was rigged to provide big wins followed by big losses, while the other deck was set up to provide small gains but almost no losses.

Card Decks

It took about 50 cards before the subjects said they had a hunch about which deck was safer, and about 80 cards before they could actually explain the difference between the two decks. However, what is most fascinating is that after only 10 cards the sweat glands on the subjects’ palms opened slightly every time they reached for a card in the dangerous deck. It was also around the tenth card that the subjects started to favor the safer deck, without being consciously aware that they were doing so. In other words, long before the analytical brain could explain what was going on, the subjects’ bodily intuition knew where there was danger, and guided them toward safety.

A similar study looked at people’s ability to predict whether a picture was behind Curtain #1 or Curtain #2; however, this was done on a computer, so there were no actual curtains involved. Just like with the card study, the researchers also measured the subjects’ subtle physiological responses. Remarkably, they found that the subjects’ bodies were able to predict the correct curtain 2-3 seconds before the computer had even decided which curtain to use.


The subjects did not always follow through with what their slightly sweaty palms were telling them to do, but the slightly sweaty palms were almost always right – in fact, they even had the ability to predict the future (by about 2-3 seconds). For gamblers who would like to have the ability to predict what’s behind a certain card, this study suggests that they should work on heightening their sense of intuition to such a degree that they can recognize when the sweat glands on their palms have opened up.

Finally, other studies have found that, when it comes to making major life decisions, such as which house to buy or which person to marry, trusting your intuition leads to better outcomes than trusting your logical, thinking brain. In one such study, car buyers who had plenty of time to pour over all of the information about their various car choices were later found to be satisfied with their purchase only 25% of the time. Meanwhile, those buyers who made a quick, intuitive decision about their car purchase were found to be satisfied with their purchase 60% of the time.

Radical Remission Survivor

While I was personally surprised to have intuition come up over and over again in my research on Radical Remission cancer survivors, the studies described above tell me that I should not be surprised at all – because our intuition often knows what’s best for us even when our thinking minds do not understand yet what’s going on. That’s because intuition operates from the part of our brain that developed at a time when hidden dangers could jump out at us at any moment – such as a tiger hiding behind bushes. This part of our brain became highly skilled at sensing immediate danger as well as places of safety. However, because most of us now live a relatively safe, day-to-day existence, that part of our brain is not triggered very often, and when it is, we are not familiar with it, so we tend to ignore its messages. However, we all still have that part of our brain, and the Radical Remission survivors I study have learned how to use it to their advantage.


Note: This post was based on an excerpt from the New York Times Bestselling book, Radical Remission: Surviving Cancer Against All Odds.


Dr. Kelly Turner is the New York Times bestselling author of “Radical Remission,” as well as a researcher and lecturer in the field of Integrative Oncology. Her specialized research focus is on radical remission of cancer, which is when someone heals from cancer against all odds. Dr. Turner holds a B.A. from Harvard University and a Ph.D. from the University of California, Berkeley. You can learn more at and also

©Kelly A. Turner 2014

About the Author
Kelly Turner Ph.D.

Kelly Turner, Ph.D., is a researcher, writer, and speaker in the field of Integrative Oncology.

More from Kelly Turner Ph.D.
More from Psychology Today
More from Kelly Turner Ph.D.
More from Psychology Today