Author’s Note: Article originally published in BrainWorld Magazine.
Many phrases and metaphors relate to the heart and the brain: “Follow your heart.” “Mind over matter.” “He has a cold heart.” “She has a steel mind.” This sometimes makes it seem that the heart and the brain are separate, each living in its own world, without connection to the other. Research shows, however, that the heart and the brain are interconnected, with one organ passing information along to the other. Importantly, we can recognize — and manipulate — our heart and brain through our heartbeats.
At the University of Sussex, Dr. Sarah Garfinkel tells the story of how emotions and cognition are embodied: how your heartbeats and awareness can shape your emotional state, ranging from anxiety levels to decision-making. These internal signals report back on the homeostatic state of the body, alerting the person to states like hunger and thirst, anxiety, and pain. This awareness is called “interoception”: the sensing of physiological signals, including heart rate. Most of us know this ability as your “gut feeling.” One way the body and brain communicate is via baroreceptors, which are sensitive to pressure and stretch in the heart and arteries. Every time the heart ejects blood, the baroreceptors analyze the strength and timing of each heartbeat, and send the information to the brain via the vagus and glossopharyngeal nerves. This is the major mechanism for fast- and short-term blood pressure regulation. It is also the primary way the body communicates the ever-changing state of the heart to the brain. Every time the heart beats, the brain flashes, and the brain’s flashes coincide with how fast and how hard the brain is beating.
The brain changes alongside the heart’s dynamic state, that is, the amygdala and thalamus — regions associated with fear and pain — affected by this heart-brain relationship. Your brain, therefore, is its own entity, but it also represents the body’s activity, including that of other organs. How your organs react to stimuli can dictate how your brain responds. The brain and body shouldn’t be separated; instead, the brain should be seen as being enmeshed with the body. This is important in offering ways of treating anxiety or behavioral and emotional issues. Making people more aware of their bodily sensations can make them more aware of emotions, and more empathetic toward others…
For more of this article, check out BrainWorld Magazine’s Summer 2018 issue.