“The heart has reasons reason cannot know.” –Blaise Pascal
Everyone has heard, at one time or another, the instruction to “follow your heart.” In fact, our daily lives are peppered with sayings that cast the heart in a starring role when it comes to emotions and decision making, from the terms heartbroken and heartless to the expression “taking something to heart.”
Some people have even contended that there may be a scientific basis for these terminologies, citing the alleged existence of “brain cells” in the heartand implying that the blood-pumping organ might indeed have a mind of its own.
But can you really think with your heart?
It’s time for some myth busting.
Let’s first take a look at the claim that there are brain cells in the heart. The human brain, like all other parts of the body, is made up of cells. One crucial cell type in the brain is the neuron, a specialized cell with structures that allow it to send and receive information from other cells using electrical signals called action potentials. Our brains contain a whole lot of neurons — roughly 86 billion.
But neurons are found in other parts of the body too, including the gut and the heart. These neurons are part of the autonomic nervous system, which regulates vital functions like digestion and heart rate.
The heart contains far fewer neurons than the noggin, and their job is not to “think” in the way that folks have misinterpreted. They help the heart react to the various demands placed on it by the body. Because the heart has such an important job, it needs to have cells that help regulate its beating. For example, our hearts must adjust every time we stand up or sit down to keep our blood pressure at the right level and ensure we don’t pass out. But this system acts largely unconsciously, which should be a relief: imagine if you had to consciously control your heart’s activities every time you moved!
The neurons in the heart do communicate with the brain by providing feedback signals, which in turn may affect our emotions. When we experience something physically, it can change our emotional state: when our hearts race, we may feel anxious. This communication does not mean the heart is thinking for itself, however: as clinical neurologist Dr. Steven Novellaexplains, “Neurons alone do not equal mind or consciousness. It takes the specialized organization of neurons in the brain to produce cognitive processes that we experience as the mind.”
So despite the presence of neurons in the heart, we can see that the heart does not have a mind of its own. Our hearts are complex, vital organs, but the association between heart and mind is best left to metaphor, not real life.