Have you ever experienced brain freeze? After you eat ice cream or slurp down a cold drink, you might feel a throbbing pain in the front of your head. This “freeze” only lasts for a few seconds and causes no damage to the brain or mouth, but it’s certainly painful! This is just one example of our brains inducing pain although no damage has been done to the body. And knowing that this happens is key to understanding why we feel pain in the first place.
What you are about to learn about pain may surprise you. We can not only experience pain because we have been “hurt,” but we can also experience pain just because our bodies are taking precautions. With this knowledge, you may be able to reduce the pain that you feel day to day and recover from injuries faster.
Does the Brain Feel Pain?
The brain responds to sensory information and integrates it with other information to decide whether or not the body needs protection. If the brain feels that we must protect ourselves, it sends out messages to the body and we experience pain.
Pain is a complicated process. Our view on what causes pain and why we experience it has changed in recent years, so use this information as a springboard to further educate yourself on what scientists have discovered about pain, how to treat it, and how to prevent it.
What Causes Pain?
Pain starts when the tips of nerve endings pick up on a variety of factors that could be signs of threats to the body. These factors include:
- Temperature changes
- Certain chemicals
For example, nerve endings inside the mouth detect a sudden drop in temperature when we eat ice cream and get to work. They let our brains know that we may be experiencing a threat, even though we are just eating ice cream.
Pain receptors “work” by sending electrical signals with information to the brain through the spinal cord. They land in the thalamus, a region of the brain that collects sensory information and processes it alongside other factors to create nociceptive information. Nociceptive information is part of nociception, the body’s response to outside dangers.
Nociceptive information may be shaped by the following factors:
- Stress and mood
- Personal beliefs about pain and the body
- General expectations concerning pain
That’s right. Do you know someone who brushes off pain or says they have a high pain tolerance? They may be telling the truth, only because they strongly believe that they are unlikely to feel pain! Someone who believes they are constantly in pain may be experiencing tissue damage, but they may also be fueling their experiences of pain and influencing nociception to continue “protecting” the body.
The Amygdala and Pain
Another part of the brain that highly influences pain (and our reaction to it) is the amygdala. The amygdala is the center of many of our emotions. It activates the fight-or-flight response when we face perceived threats. But it likely also lets us know that pain is unpleasant.
How do we know this? Scientists conducted studies on rats who experienced pain from needle pricks. They observed when the mice experienced a prick, neurons within the amygdala lit up. Identifying these neurons, the scientists took one step further. They turned off those neurons and pricked the mice once again. The mice had previously felt unpleasant but without those signals from the amygdala, they did not mind the sensation of the needle prick.
Don’t like being in pain? You can thank your amygdala.
Acute vs. Chronic Pain
The body experiences one of two types of pain: acute or chronic. Acute pain is short-lived - the experience of feeling pain after touching a hot stove goes away rather fast. Chronic pain lasts for months on end.
Pain can become a vicious cycle in so many ways. When pain receptors are triggered at a high frequency, they are more likely to send more powerful signals to the brain and induce pain. The brain may respond by sending more stress sensors to pain receptors, making them more sensitive.
The thalamus will collect all the information it may need about whether or not the body is experiencing a threat, then send that information to the cortex, the amygdala, the hypothalamus, and the anterior cingulate gyrus, which helps to regulate pain and stress responses. In some cases, the thalamus may also directly communicate back to the spinal cord, and pain may be increased or decreased. Depending on the type of threat posed to the body, the brain may also send out messages that kickstart the immune system.
Sleep and Pain
Chronic pain may begin as a reaction to chronic diseases like fibromyalgia or IBS, but the chronic pain itself may lead to more chronic pain. Pain, for example, often inhibits a person from enjoying a full night’s sleep. Poor sleep exacerbates chronic pain, causing more intense pain for long stretches of time. Sleep has even been recognized as a potential treatment for chronic pain! During sleep, the mind and body are able to reset, regulate various systems, and boost immune system functioning. All of this has a positive effect on pain.
Can You Feel Pain with Brain Damage?
Yes and no! No two cases of brain damage or traumatic brain injury (TBI) are the same. In some cases, a TBI or brain damage may damage the nociception process. Patients with TBI are more likely to experience higher levels of pain and chronic pain.
Pain to the nerves themselves may cause a strange burning or tickling sensation. If the nerve is constantly compressed or being activated, that pain can last for a long time or be more intensified.
If you have experienced an injury or are feeling new types of pain, reach out to a specialist. They may be able to prescribe medication or devise a different type of treatment plan that directly addresses your unique pain. Remember, no two cases of injury are the same, and not every treatment will address pain.
How the Brain Reduces Pain
One way the brain reduces pain is through the release of endorphins. Endorphins are hormones and natural painkillers. Have you ever experienced a “runner’s high,” where the pain from your run melts away and you suddenly feel happy to be exercising? You can thank endorphins for taking away your pain.
The Impact of Anxiety and Depression on the Brain
No one wants to be in pain. The unpleasant feelings of pain cause depression and anxiety in many people. This, too, becomes a vicious cycle. Our mood impacts our nociception and influences whether or not the brain decides that the pain response is necessary. This feeling of pain can make us feel anxious, triggering the fight-or-flight response. The fight-or-flight response stiffens our muscles, negatively impacts our sleep, and prevents the body from properly regulating itself. All of these additional factors may lead to more pain.
So how do we break this cycle? Many recommend cognitive behavioral therapy (CBT). CBT operates on the principle that our thoughts and feelings make us who we are. Our thoughts influence how we see the world, make judgments about ourselves, and experience pain. By addressing memories of pain or our expectations of pain through CBT, we may find that our pain is reduced and we can live life with less anxiety.