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Are feelings in the body or the brain?
We know that thoughts and emotions are rooted in our brains. But our experiences of the external world – touch, smell, sight, pain – depend on the brain too. For example, some people with spinal injuries can touch things without ‘feeling’ them. This happens because the nerves send signals that the brain is not receiving or is unable to interpret. The opposite happens with phantom limb pain. More than 80% of people who have lost an arm or leg still feel that missing limb. The brain is generating feelings with no stimuli coming from the outside.
When it comes to pain and sensation, the brain rules.
Why do we feel pain?
Pain hurts – it is an unpleasant sensation. That’s exactly why ‘acute’ pain – pain we feel when we hurt ourselves (cuts, bruises, or broken bones) – is helpful (p. 100). First, pain alerts us that we are hurting ourselves so we stop. Second, pain teaches us to be careful. You know that old saying “Once burned, twice shy”? Pain teaches fast.
Patient: Doctor Doctor it hurts when I do this.
Doctor: Don’t DO that!
What do emotions have to do with pain?
All pain is in the brain. We experience healthy, acute pain when the brain senses tissue damage.
How does this happen? A stimulus activates receptors in your tissue (you fall and skin your knee, triggering specialized nerve cells). These receptors send signals to the brain through nerves and the spinal cord (a process called nociception). When the signals reach the brain, they are interpreted and given meaning. Will we experience pain then? It depends.
- IF the signals are sufficiently strong and
- IF the brain may think the body is in danger,
- THEN we experience pain1.
- IF the brain may think the body is in danger,
If you fall, many signals are sent from your knee to the brain – pressure, tearing, wet. This can be automatic (the strength of the signal immediately signals damage, you flinch even before you know what happened, then you feel pain).
It can also be influenced by what you know. If you see blood, it can change whether your knee feels tickly, weird, or painful.
Strong physical sensations also trigger a whole cascade of emotional reactions that can change what we feel. For example, some runners interpret their pounding hearts, struggling lungs, and screaming muscles with satisfaction (‘Pain is weakness’s way of leaving the body!’)
That’s in the context of running. If they woke up from a sound sleep with those sensations, they might experience them as fear (I had a nightmare!) or as pain (I’m having a heart attack!) and head to the emergency room.
Strong sensation is felt as pain if it is threatening.
The role of the amygdala
The amygdala is part of the brain central to feelings like fear, anxiety, and anger. It also processes punishments and rewards. Burning your hand quickly teaches you not to touch fire. Rewarding experiences make it more likely we do something again. If you had fun at an amusement park, you’re more likely to go back.
An amusement park is a good example of how the amygdala can change how we feel – and thus the power of rewards to change behavior.
Think about how it feels to go ride a roller coaster. What makes it fun for lots of people is the thrill. We feel danger from the speed and sensation. Despite that, we also feel pretty safe because of the precautions and seat belts and seeing other people laughing as they get off the ride damps down our fear. Both the fear and the pleasure feelings we experience on a roller coaster are mediated through the amygdala. If we didn’t trust the amusement park, a roller coaster wouldn’t be fun, it would be terrifying.
The amygdala’s response differs by context
Have you ever ridden a roller coaster by yourself? It’s a lot more fun with a buddy. Most people – particularly teenagers – have much more fun doing risky things when they’re with friends. That’s because being with others activates the amygdala and enhances feelings of reward. This even happens when we just think our friends are watching or if we imagine sharing what we’re doing on Instagram or Facebook.
The same is true of pain.
We experience sensations very differently depending on what emotions go along with them. When we are depressed, scared, or anxious, the amygdala interprets injury and sensation as threatening. What happens?
Is that why distraction helps?
It seems impossible that someone in pain can be laughing and playing a videogame one minute, then overwhelmed and unable to set the table or focus on homework. But it happens all the time. The positive emotions and activation of the brain – plus the conscious focus on the activity instead of the pain – changes how pain is experienced.
That’s not faking it. It’s neuroscience.
The role of the amygdala in pain is one reason most pain professionals recommend people in pain work hard on getting out and seeing people, meditate or exercise to reduce their stress levels, and get treatment for depression and anxiety.
When you feel the world is a safer and less threatening place and that you are more powerful and capable, the same sensation is interpreted differently.
When you’re having fun, the anxiety and danger centers of the brain ratchet the experience of pain way down. The pain is still there, but it’s much easier to deal with.
In other words, when you feel happy and strong, pain hurts less.