Your heart affects how you feel — literally.
A new study from researchers in Germany explored the effects of why the human body’s sensitivity to outside sensory stimuli changes with your heartbeats.
This study draws upon the scientists’ previous research, which determined individuals’ ability to identify external stimuli, such as an electric shock, was weaker during systole [SIS-tolee], when the heart directs blood outside of the heart, than diastole, [di-AS-tolee] which refills it.
New research linked this shift in sensitivity to a unique feature of the electrical activity inside the brain. This feature, related to our state of consciousness, is responsible for communicating the degree to which a sensory stimulus is interpreted as unexpected. The more surprising the stimulus, the stronger the signal, indicating the body needs to pay close attention.
In addition, researchers also discovered that the more aware an individual was of their heartbeat, the worse they were at detecting external stimuli. The findings suggest that the brain is capable of quickly switching attention between internal sensations, such as a heartbeat, and external ones. However, we cannot direct our attention to both at the same time.
The research presents a variety of implications for health care. Notably, it may indicate that the bidirectional communication between the heart and brain can become disrupted during a heart attack or stroke, which affects blood flow. This could lead to better understanding of the cognitive impairment that many people with heart disease experience.