How the Body Feels Pain

July 8, 2013September 27, 2016 / Thomas Cohn, MD

Pain is a complex issue. Acute pain is usually related to one of the following:

Tissue damage
Perceived damage
Injury

Chronic pain can be associated with chronic damage or a short circuit in the transmission of pain signals. Treatment of pain depends on the cause. In acute pain, if you treat the cause the pain will normally go away. However when pain becomes chronic, treatment often does not take away all the symptoms.

Pain Signals & Sensory Stimuli

Chronic pain is generally defined as pain lasting longer than 3 to 6 months. Often, it outlasts the initial injury. In some ways it becomes independent of the initial stimulus or cause. Damage may be ongoing, and there may be a chronic inflammatory response, all causing ongoing sensory stimuli, which are subsequently linked in the spine and brain, to the perception of pain. Often, non-painful sensory signals then become linked to nerves that previously transmitted pain signals. Normal signals then become perceived as pain.

All sensory signals are processed in the brain at some level. The brain has an incredible ability to determine the importance of each signal and then form a response. Depending on the circumstance, the brain can ignore the same signal that would be horrific pain. For example, we all have heard about soldiers in war who have been shot, but continue fighting with no loss of focus. Therefore, the real key player in all responses to pain signals is the brain and its interpretation of the signals.

Blocking Pain Signals

The key to treatment of pain then is altering the brain’s ability or desire to interpret sensory signals as pain. Blocking signals can be done anywhere along the path from the sensory receptor including:

The peripheral nerve to the spinal cord
Along the spinal cord pathways
In the brain itself

Although pain can be treated in multiple ways, all treatments try to prevent transmission and interpretation of sensory signals that are perceived as pain. There is no magic bullet and no one treatment alone that will work for everyone.

The simple reason why there are so many treatments for pain is that there are so many ways to alter signals that are perceived as pain. Medications have been designed to affect sensory impulses at a variety of locations from the skin and periphery to the spine and brain. Furthermore, there are a variety of techniques from proper movement, to acupuncture, to psychological training that can effectively treat pain.

Acute Pain vs. Chronic Pain: Definitions & Differences

June 3, 2013September 27, 2016 / Thomas Cohn, MD

There are many definitions of pain. Because pain is often subjective, everyone will define and describe it in their own personal terms.

Dictionary vs. Medical Definition of Pain

The dictionary describes pain as physical suffering or discomfort caused by illness or injury. Medicine becomes very technical in its description of pain, often concentrating on the physical aspects, structures involved, and trying to determine if it is “real.” The International Association for the Study of Pain (IASP) defines pain as:

“An unpleasant sensory or emotional experience associated with actual or potential tissue damage, or described in terms of such damage.”

Pain has both physical and emotional correlates. If someone has pain, there is usually a physical cause in the body that needs to be found. Pain may also have significant emotional correlates in the brain. The processing centers in the brain for many pain signals sit next to the areas that control emotional stability. Therefore, if people have significant amounts of pain, spread of pain signals to emotional areas of the brain can easily occur, affecting mood and depression.

Pain is always subjective. It is a learned experience, and it is very individualized. A person learns what pain is through experiences related to injuries as a child and as they grow up.

Acute vs. Chronic Pain

In medicine, pain is the interpretation of certain sensory signals, generated from a variety of receptors in the body. When the sensory signals are ongoing, most people interpret these as pain, and seek treatment to relieve them. There are two primary types of pain:

Acute pain is from definite tissue injury and will fade after the cause is identified and treated. A common example is cutting a finger – it hurts, it heals, and the pain is gone.
Chronic pain occurs when damage causes ongoing sensory signals for long periods of time, and in some degree becomes independent of the actual tissue damage. This type of pain is difficult to stop, and often the best treatment is working on systems to manage the pain.

Understanding the complexities of pain, the body, the sensory nervous system, and the overall interactions in the body are some of the important aspects for a medical doctor who treats patients with pain. A good pain physician understands people and medicine and how all these interact, allowing them to find the causes and improve the quality of your life.