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Seeking Direction in Pain: Why Telling Right From Left Is Hard

Updated: Jul 28

A blue image of a brain with right and left pointing road signs and the title "Seeking Direction In Pain"

If you struggle with your sense of direction and you have chronic pain, you're not alone. While some may be inclined to blame it on growing up in the "GPS Generation", there may be more to it than that.

People living with chronic pain have been shown to struggle with their ability to differentiate right from left (also called laterality). This is true for people with a wide variety of pain conditions in different body regions including the arm, wrist, hand, leg, knee, and even the face (1).

While being directionally challenged can be inconvenient, most people are able to compensate for this by using the GPS technology on their phones. Being able to tell right from left, however, may have an impact on your body's pain processing and be worth training.

If your body doesn't know the difference between the right shoulder and the left shoulder, you may start to feel that pain you had on the right is now also on the left side. In short, if you can't tell the difference between right and left, it's possible the same effect is happening in your brain, adding the sensations together and making life more painful. It makes matters complicated that your nerves are pretty good at addition and not very good at subtraction.

If your body can't tell the difference between two points on a pair of tweezers touching your skin because they are close together, it will add the pressure of both points together and you'll feel it as one. This is a problem for people with pain. It can mean the nervous system is amplifying a pain signal and making it more intense because it can't clearly differentiate what it's feeling.

Fine tuning our sensation can help to decrease the intensity of chronic pain by simply helping recalibrate the nervous system to better interpret what we're feeling more accurately.

The best part is, you can do this at home for minimal cost by doing what's called laterality training, and two point discrimination training.


What is laterality training?


Laterality training is challenging your body to differentiate right from left in a variety of situations to help improve it's accuracy. This will help sharpen your brain's map for the right and left side of your body. As an added perk, it may also help you to be better at navigation and directions.

If you prefer the more guided approach, there are apps that will take you through a laterality program, like the Recognise App or the Orientate App. Unfortunately, Recognise requires you to pay for each body part which can get pricy at $6.50 per app if you have widespread pain. Orientate offers the first few levels free, but in-app purchases are involved after that. There are some advantages to the app, in that the images are specifically selected and the program is able to give you feedback. If you aren't ready to spend the money when you aren't sure if it works for you yet, there is another way.

If you prefer the more economical version, you can practice laterality training with a magazine, or scrolling through images on Pinterest on your phone or tablet.

First you'll choose a body part to search for. It is generally easier to start with hands (the side of the hand the thumb is on tips you off to which direction the hand is facing.) You may have chronic pain specifically in your shoulder, however, or your knee. Once you get the hang of the laterality training searching for hands, you'll eventually want to work on practicing for the part of your body that is painful.

Get your magazine ready and start with all of the images face up; it will be easiest this way. As you turn the pages of your magazine, try and find every right hand (or whatever body part you chose to work on). This may be somewhat challenging at first, but you will get better with practice. As you make mistakes and realize them, redirect your attention to the correct hand in the picture.

An infographic on laterality training with each of the steps listed

When you get to about 80% accuracy in selecting the correct hand consistently, it's time to increase the level of difficulty. Turn your magazine 90 degrees counterclockwise. Now your brain will have to work harder in differentiating the right and left hands because the position of the image has changed. This will further hone your body's skill to tell right from left regardless of position.

When you reach an accuracy level of 80% or better, simply turn your magazine another 90 degrees so that it is now upside down and repeat the process. When that gets too easy? You guessed it, turn it another 90 degrees.

If you don't have magazines lying around, you can use a feed of images on your phone or tablet. Just place the tablet on a flat table top so that it doesn't automatically adjust the screen to your position as you turn the tablet in the 90 degree turns.



What is two point discrimination training?


Just like the title implies, the goal is to help your body differentiate between two points touching you at the same time at as close of a distance as possible. Different parts of your body are more capable of doing this than others. For example, the palm of the hand is more sensitive than the skin on your lower back.

While you can buy two point discrimination testing devices that are at set distances apart, the more economical version is to use a large paperclip. The advantage to a paperclip is that the metal is fairly flexible, and you can bend it to different widths between the two points. This is convenient for training because you can easily make changes depending on where on the body you're training.

First you want to assess how far apart you are able to tell the difference between one and two points. Have another person quiz you while your eyes are closed. The person quizzing you will tap you with either one of the two points on the paperclip, or both points. Your job is to tell them whether you are feeling one or two points. If you are consistently accurate in answering correctly (about 80% of the time or more), then the person doing the quizzing can bend the paperclip to make the two points a little closer together. Eventually the points will be close enough that you can't tell the difference between them consistently.

Measure how far apart your paperclip points are when you first reach a distance that becomes difficult. This is what you want to set your paperclip to when you work on yourself.

If you are practicing with someone consistently and they can quiz you all the time, that is great. If not, you can do this yourself and it's ok for training. In fact, if your body is having a hard time feeling the difference between the two points, when you can see that you are touching your skin with both, the visual feedback helps your brain learn what it should be feeling and can help it to interpret the information more accurately.

Likewise, if you are controlling the paper clip, and you know that you intend to touch yourself with both points, your brain will tell your nerves to expect touch in two places. This can also help fine tune the nervous system to feel what it is supposed to be feeling.

As you practice alternating between touching yourself with one, or both points of the paperclip and feeling the difference, you may notice that you feel like it becomes easier. You may be able to close your eyes now, and still feel the difference between one and two points consistently.

If so, it's time to retest; have someone else check. Having another person check means that your brain won't produce the right sensation because you know it should be there. Our brains and our nervous systems rely heavily on expectations, so it's easy for them to do this. Our brains are excellent at finishing other people's sentences, predicting where the ball will bounce next, and anticipating all kinds of different things.

If you test well, at the previous level of distance between the two points, your tester can move them closer together until you begin to struggle again. Then you can repeat the process and train at the new level.

So what is the goal? To help give you a sense of "normal", there is some data out there on what distance a typical person can differentiate between two points. If you need some direction, here is some data for a few different body regions:


A diagram with research data and images of the neck, back, hand and foot.

Citation credit for this research article and the associated image can be found here: (2)


The typical person was able to tell the difference between two points until about 10.4mm on the palm of the hand, 20.9mm on the sole of the foot, 55.5mm on the lower back, and 45.9mm on the neck. (2)

You'll notice that some areas are more sensitive than others. The hands that we use to interact with our environment and engage with most objects are the most sensitive, followed by our feet. Our lower back, which isn't as heavily involved in sensing our interaction with things in the world, on the other hand has a much larger distance between two points.

The ultimate goal of these types of sensory training is to sharpen the maps that your brain has for your body's sensory system. Bringing clarity and focus to sensation in the brain can help people have less pain that shouldn't be there.

If you're interested in more ways to train your brain and your sensory system, see Train Your Brain: Sensory Mapping and Stereognosis.



This post is intended for educational purposes only and is not a replacement for individual medical advice from a licensed healthcare provider. If you are interested in an evaluation of your specific case, call or click to request an appointment.



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