The internal state of your body affects how you perceive the world - in ways you are often not even aware of. Understanding both the brain and body, and how they work together, is vital to understanding mental health.
Walking along the street on a hot sunny day, you may veer towards the shade. After you been sitting down for hours, you get up and stretch. Why? Because of the state of your body; you are too warm, or in pain.
It may seem obvious that the state of your body controls many of your actions. Hunger and thirst make you feel a need to eat and drink, for example. But signals from within your body don’t just affect your behaviour, they can affect thoughts and even emotions.
A sense of what is happening inside the body is called ‘interoception’. This sense encompasses feeling everything from temperature, to pain, heartbeats and breathing. It is through interoception that the state of the body can contribute to, or intensify, emotion.
Dr Hugo Critchley and Dr Jessica Eccles, based at Sussex University, are leading research into interoception and mental health. They are focussed on understanding the connections between heart rate and anxiety. Using these insights, they are developing new treatments to reduce the debilitating symptoms that anxiety can bring.
Head Vs Heart
If your heart rate speeds up, how do you feel? If the increase is during exercise, it usually wouldn’t come with any particular emotion. But if your heart rate increases in response to a threat (think tiger), you may also feel afraid or anxious.
There are other reasons for an increase in heart rate too. Participants in one study were asked to prepare a speech that they would then be assessed on. Their heart rates increased and they became worried about the task. Or, your heart rate may increase when you see someone you love.
So a fast heart rate alone wouldn’t necessarily be associated with anxiety or panic. The emotions that go with a fast heart beat depend on the situation.
Can you feel the beat?
It’s not only different situations that can contribute to anxiety. Some people are more accurate than others at judging changes within their own bodies. Researchers have found that people who are particularly good at sensing a fast heartbeat are more prone to anxiety. They may experience emotions more intensely, and are more sensitive to pain. They can also be more empathetic, better at emotion regulation and have a stronger sense of self.
Understanding exactly how heart rate, and the sense of it, is linked to anxiety is helping the Sussex researchers develop new treatments.
Anxiety in autism
Dr Critchley’s team have found that many autistic people are both very sensitive to changes within their own bodies and inaccurate at judging them. They found that this mis-match between what is perceived and what is expected is associated with anxiety symptoms.
To help those affected, the team have developed a new training therapy. Delivered through a mobile phone app, it trains users to improve perception and interpretation of their own heartbeat.
This is the first treatment of its kind - aiming to prevent anxiety by helping people interpret their heartbeat. We are supporting a clinical trial to see how effective it can be for autistic people with anxiety.
Anxiety and hypermobility
Hypermobility, where joints move beyond a normal range of motion, affects 1 in 5 people. People with hypermobility are also more prone to anxiety. Dr Jessica Eccles is investigating this link - and has shown this increase in anxiety can be explained by the fact that people with hypermobility are more sensitive to changes within their bodies, like heart rate.
Dr Eccles is developing a new psychological treatment for people with hypermobility and anxiety. We are funding research to see how effective the therapy can be.
The whole person
Using state of the art brain scans, the teams are also looking in detail at how the heart and brain signal to each other. This builds on Dr Critchely’s pioneering work which uncovered precise areas of the brain involved in interoception.
By understanding both our bodies and our minds, and how they work together, we can not only better understand mental health, but also develop new and innovative treatments to improve the lives of those facing mental illness.
Last updated: 13 September 2018
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