Acute
pain feels different than chronic pain. When pain is acute the brain helps
modify the pain by diminishing it. When an acute pain occurs the brain's modifier
chemical's come into play and work to decrease the acute pain signal that is
suddenly bombarding the brain. This is why pain diminishes quickly after an
injury. This is actually a highly adaptive mechanism that has many more chemical
and anatomical reactions than shown in this simple animation.
On the other hand chronic pain is quite different.
When chronic pain sets in the spinal cord and brain have been bombarded by pain
signals at a high intensity for a long period of time. Due to a complex series
of chemical reactions and an adaptation by the spinal cord, the incoming pain
signal begins to be amplified in a phenomenon known as windup
pain. The pain signal that reaches the brain is much stronger and the ability
of modifier pathways to change it are greatly decreased.
