Recently, I decided to participate in a study being conducted in the Wager Lab in the Department of Psychology & Neuroscience at the University of Colorado at Boulder. The Wager lab deals with the neuro pathways associated with processing and regulating physical and emotional pain. Specifically, they examine and attempt to identify biomarkers in the brain which relate to different types of pain and how certain psychological factors influence the placement and movement of these biomarkers. This research is extremely important as it could aid in clinical intervention in pain related conditions (fibromyalgia, multiple sclerosis, etc.) by allowing medications to target these biomarkers within the brain.
I was put into an MRI (and was temporarily reminded that this is the point in the House episode where the patient starts bleeding or seizing) and had a probe attached to my wrist at six different positions (it was moved from position 1-6 at the end of every trial). This probe was connected to a machine which mediated heat, sometimes the probe did nothing and sometimes it heated to the point of holding a warm cup of coffee without a sleeve. A computer screen was placed within in my view and I had a mouse and track ball in order to make decisions within the test. I was given the option of a circle shape or a diamond shape and was required to choose one by clicking either the left or right tracker. When I had chosen an option I was either shown a severely violent picture (injuries, torture, medical conditions, etc.), a neutral picture (someone grocery shopping), a mild heat which felt similar to a heat pad, or ‘severe’ heat.
The idea was that you would attempt to avoid the most unpleasant sensation via your choices. So, if I chose a circle and got a heat response I would then choose the diamond, if I was shown a neutral picture after picking a diamond I would then choose the diamond again. Sometimes the pain was unavoidable, and other times I was able to find patterns and avoid unpleasant sensation. While I was preforming this game an MRI was continuously taking pictures of my brain and recording where the most blood flow was. Later the researchers will be able to match the reaction in my brain (for example, excess blood flow in my thalamus) to the stimulus I received in the MRI (most likely a heat stimulus). It will most likely also show them the differences in blood flow between seeing others in pain (graphic pictures) and being in pain personally (heat stimulus).
So, how does pain work exactly? Well, as you may have guessed it all has to do with the nervous system. The nervous system is made up of three main parts: the brain, the spinal chord, and the sensory/motor nerves. The brain and spinal chord make up the central nervous system, where as the nerves run all around your body from the tips of your fingers to deep within you back. All three parts of the system work together to communicate an environmental pain and to react accordingly.
Let’s say you step on a Lego (we’ve all done it) your sensory nerves at the tip of your feet being to write a letter furiously, put it in an envelope, place a stamp on the front and drop it off at the spinal chord. The spinal chord then, much like the post office, delivers this note to the brain who then reads it, makes a decision, picks up the phone and calls the motor neurons and tells them to move away from the source of the pain… and probably say a few choice curse words. In reality these phone call and letters are complex chemical messages which are sent faster than we can even react.
In this study, they are specifically looking at the decision maker of the pain message, the brain. When the sensory nerves alert the brain to a pain stimulus the thalamus takes control of the message where it attempts to make sense of the situation. Where did this pain come from? How does this compare to other types of pain we’ve experienced before? Have I stepped on a Lego like this in the past? Your limbic system which is associated with generating emotions is also triggered, hence why you then cry or scream, this reaction helps you associate bad things that could damage your body with feeling upset, hopefully leading to avoidance in the future.
Though we understand the basic ideas, we’re still unsure of the specific systems, chemicals, and receptors responsible for this amazing communication between brain and body. Hopefully, my small contribution to science can help us reveal the beauty of our evolution and help others with pain conditions.
Also, hopefully you got the house reference in the title, him being the poster child of chronic pain.