Do you decide what you are going to do, or does your brain decide? Indeed, do you have free will, the freedom to choose your future behavior? Or are you just a puppet manipulated by your brain?

The problem is that even before you decide whether or what you will do, distinctive electrical activity in your brain precedes the moment in which you decide, by about one-half of a second. Only a few electrodes attached to your scalp are enough to detect this distinctive activity—the readiness potential (RP)—which precedes your conscious experience of the decision to act.

That the RP precedes our conscious decision to perform an action has been replicated by many EEG studies. Some who have reflected upon this finding even believe that it implies human beings are not free. That is, we cannot freely choose what we do. This is important because if we cannot freely choose then we are not responsible for our behavior. And if we are not responsible for our behavior, then we should never be praised or blamed for what we do.

Not everyone agrees with this interpretation of the relationship between RP and human behavior. After all our behavior is dependent upon our brain, and our brain comprises electrical and chemical activity. So perhaps it should not be surprising that we find RPs preceding the feeling of free choice. But among scholars and scientists there is no consensus as to how we should understand the RP-behavior relationship.

GIMBC PI, Dr. Hyeongdong Park, has recently published results of a detailed investigation of RP and our ability to imagine, even when we perform no actual behaviors. More than this, Professor Park has also demonstrated that there is an important relationship among RP, our imagined actions, and our lungs—specifically, our patterns of breathing! His study is published in the December 2022 issue of Neuroimage, which is ranked 3rd among all Neurology and all Cognitive Neuroscience journals.

It has long been known that who we are and what we decide to do is intimately connected to the activity of our brain. Only in recent years, however, have neuroscientists begun to investigate how such brain activity is related to other parts of our body. What Professor Park has shown is that when we choose to do something not only is our brain involved, even our respiratory system is involved. In a word, how you breathe partially determines how you make decisions. Indeed, this is even true when we only think about or imagine performing an action!

Why are these findings so important? First, they suggest the possibility that by altering our patterns of breathing, perhaps we can even alter how or what we decide to do. Second, one of the things that is special about humans is that thinking is private—other people cannot tell what you are thinking just by looking at you. Professor Park has identified a mechanism whereby we can gain insight into the mental activity of others, even when we observe no overt behavior. Third, there are many types of neurological disorders which cause people to lose control of their bodies. The results of this study suggest one possible means whereby we can develop techniques for body-machine interface, thereby helping these patients to perform actions in the world, and improve their quality of life by enabling them to be more independent. And, finally, some patients have been diagnosed as “vegetative” (lacking conscious experience), but we know that 40% of these patients are misdiagnosed. Professor Park’s studies suggest one means whereby we can detect conscious experience in the brains of “vegetative” patients, even when they are completely unable to respond behaviorally. In other words, these discoveries can help neurologists to improve their diagnoses, and save patients who might otherwise be abandoned as hopeless.


Park HD, Piton T, Kannape OA, Duncan NW, Lee KY, Lane TJ, Blanke O. Breathing is coupled with voluntary initiation of mental imagery. Neuroimage. 2022 Dec 1;264:119685. doi: 10.1016/j.neuroimage.2022.119685.