Scientists have found that chronic pain can affect not only the physical condition, but also the psyche of a person, determining his feelings, thoughts and beliefs.
Approximately one in ten people in the world is faced with some kind of chronic pain. More people suffer from them than from heart disease, diabetes and cancer combined. And in some regions of the planet, every fourth person is subject to constant pains of one or another genesis.
Gamma-aminobutyric acid (GABA) is known to play an important role in signaling in the brain, inhibiting activity throughout the nervous system. In particular, in the prefrontal cortex of the brain, the suppressive activity of GABA limits communication with other areas, such as the amygdala.
Working in balance with the stimulating neurotransmitter glutamate, this signaling system ensures that our emotions support us at the right times without causing undue stress. Animal studies have shown significant differences in the amount of glutamate activated in the medial region of the prefrontal cortex when living things are in chronic pain.
The same is observed in people who are exposed to constant pain: the level of glutamate in their brain decreases. Nevertheless, the exact link between chronic pain and changes in the emotional sphere in humans has not yet been identified.
Researchers from the University of New South Wales (Australia) used advanced imaging techniques to scan the concentration of neurotransmitters in 48 volunteers, some with chronic pain and some without. The work was published in the European Journal of Pain.
As a result, the researchers were able to find that ongoing pain does correlate with a decrease in GABA levels, as well as with a person's emotional responses, thoughts and actions. Chronic pain is associated with sleep disturbances, increased stress, depressive symptoms, anxiety and guilt.