Jul 21, 2020 06:00:00

Fear and anxiety depend on 'heart movement'

When the body is in danger or nervous, the palpitations become faster, and the movement of the heart changes depending on the emotion.At the same time, depending on whether the heart is contracting or expanding, the person's 'anxiety' and Research has shown that 'fear' can change. There are many interesting studies showing that even the perception of pain changes depending on whether the heart is in systole or diastole.

Heart–brain interactions shape somatosensory perception and evoked potentials | PNAS

https://www.pnas.org/content/117/19/10575

PsyArXiv Preprints | Interoceptive cardiac signals selectively enhance fear memories
https://psyarxiv.com/4qt9m/

How Your Heart Influences What You Perceive and Fear | Quanta Magazine
https://www.quantamagazine.org/how-your-heart-influences-what-you-perceive-and-fear-20200706/

Only in the second half of the 19th century , psychologist William James and doctor Karl Lange , discovered that 'emotion is the brain's perception of certain body changes in response to stimuli.' At that time, two researchers described how emotion and body are linked, such as 'fast palpitations and shallow breathing increase emotions such as anger and anxiety,' and subsequent research shows that emotion and body are linked. Many examples have been discovered.

The movement of the heart is roughly divided into a 'systole' when the myocardium contracts and drains blood, and a 'diastole' when the myocardium relaxes and blood is taken up. Since around 1930, it has been said that “systole relieves pain”, but recent research has confirmed that the pressure sensor of the heart sends a signal to the brain during systole. Although the brain constantly integrates and balances external and internal signals, it cannot simultaneously pay attention to all stimuli. Therefore, when the internal signal is being sensed, the processing of the external signal goes to the back, making pain less likely to be felt.

In a study published in June 2020, 'When a person is given a slight electrical stimulation to his fingertips, it is easy to detect pain when the heart is in diastole and difficult to detect during systole'. Was shown. In addition, subjects with a large nerve response to heart activity were less sensitive to stimuli. 'It's very interesting that our perception changes in milliseconds,' said Ezra Al, a PhD student at Max Planck Institute for Human Brain Science and lead author of the study.

Meanwhile, a neurologist at the Brighton & Sussex Medical School, Sarah Garfinkel, announced in 2014 that the processing of fear and compulsive stimuli was not suppressed during systole.

The contractile activity of the heart stimulates the

amygdala, which is activated when feelings such as anxiety and fear. When Garfinkel and his colleagues showed a 'human face' to the subject in an experiment, those in systole perceived a 'terrifying face' as a stronger emotion. However, when he showed other facial expressions, he evaluated the emotional strength as low, and the results were in line with the idea that 'stimulation is suppressed during systole'. In other words, only anxiety and fear among emotions are not affected by the suppression effect of the heart.

Garfinkel commented on the reaction: 'When your heart is beating fast and you're in a state of fear, you don't want to be sensitive to pain because you have to run over broken glass and twigs to escape the threat. 'We should be wary of the threats that exist, because fear is what allows us to survive.'

A study published in March 2020 also showed that eye activity was more active during systole, and that the eye was more likely to be fixed on the target during diastole. When the eyeballs move fast, we do not look around and are considered to be in a form of blindness.

'The systole is when information processing becomes dull, the sensitivity to the world is lowest, and when the inner world is in control.' 'When the consciousness is not directed to the outer world, the movement of the eyeball changes and becomes blind. The result is that it makes sense,' Garfinkel said.

The results of the above studies also indicate that people with anxiety increase their ability to process systolic anxiety. The results of these studies are believed to be useful in the treatment of certain phobias and PTSD.