Brain Maps

Did you know that our brains have maps of our bodies? There’s a fancy scientific word for them—the homunculus, and these maps have been extensively studied. Each part of your body has an area in the brain that corresponds to it – receives information, interacts with it, and informs and is informed by it. Some parts of the body have a bigger section in the brain, others have a smaller section. Scientists have done research to map out these sections and have created images and models to help people understand this relationship, and you could spend years learning more about this and never fully understand all the complexities. So, let’s talk about the relevance of brain maps to pain, health, and the way we move.

When we look at a map of the world or a map of our state or city, things pretty much look the same from one map to another, i.e. the lines are drawn pretty much in the same spots, regardless of who made or drew the map of a particular region. Those do change over time, as boundaries shift, or countries change in size, but those shifts are slow. That is not the case with our brain maps. These changes can evolve quickly, sometimes in just minutes, hours, days, or weeks. And why does that matter? Well, you want your brain and your body to be well connected. If you are walking around the house and the brain suddenly forgets the fact that you have a left leg, you might trip and fall or run into furniture or harm yourself in some other way. Obviously, this analogy seems silly, because our brain isn’t going to suddenly forget we have a left leg. But our brains can “forget” about certain parts of our body over time with pain, immobilization, or fearful avoidance of movement. How is this possible?

Let’s first think about how maps are created. Consider a previously unexplored area of the world. Making a map just based on what you think is there would not serve you at all if you needed to visit that part of the world. Instead, someone must explore that region, observing, touching, moving through, and generally interacting with their environment in order to understand and then represent it. In a similar way, our brains require that our bodies interact with the environment, receive sensory input, and move and function in order for our brains to understand our bodies. This is part of why, if you were put in a cast for six weeks because of a broken arm, your arm might not feel “right” or like a normal part of you when the cast first comes off. That’s because, since the brain is receiving minimal relevant information from that area (movement, sensation, etc.), it simply begins to pay less attention to it. The brain’s map of that part of your arm becomes smaller. Happily, though, it works in reverse, as well. Once the cast comes off, and you start using your arm, the brain begins to pay more attention to that area, and the “arm map” in your brain grows again.

But why does this matter? Or maybe the real question is, when does it matter? Most of the time, the brain and the body interact in this way and our brain maps are constantly changing and evolving and it affects our lives in no relevant way. But sometimes, when people experience chronic pain or a long-lasting injury, they begin to stop moving. This is initially a perfectly natural response to pain, but when it continues long past the point of providing protection for the body and becomes a chronic response, it can begin to interrupt the “brain-body connection”. This, in turn, begins to shut down the brain map of the painful area, making it smaller and smaller, until the brain cannot attend positively to that area. Chronic and complex pain is complicated, and there are many other factors at play in these situations, but the lack of ability of the brain to perceive the painful area appropriately is an important one. It can lead, among other things, to people feeling like their limb just doesn’t belong to them, having difficulty processing pain and other stimuli in that area, and having significant difficulty with mobility and movement related to that area.

But there is hope! Remember when I said these brain maps can remodel within just a few minutes, hours, or days? We can do things to help that area send more positive messages to the brain. This is one of the many benefits of exercise for recovery. Massage and other forms of sensory stimulus to the area, such as exposure to different textures, can also be helpful as well. The bottom line is, providing movement and sensory stimulus to a painful area is valuable, because (among many other things), it helps to re-establish the link between the body and the brain, ensuring that the brain’s map of the body is accurate and functioning appropriately, and as a result, helping you to function appropriately as well.

If you need help with recovering from an injury and getting back to the activity that you love, reach out to your local Hulst Jepsen Physical Therapy clinic today. Schedule a free consultation to determine if physical therapy is right for you or if you just need some tips and tricks to get you there. Click Here to Schedule

Learn More About
the Author

Sarah Hyde, DPT, CIDN