"Cortisol, a hormone produced by the adrenal glands, is sometimes called the 'stress hormone' as it is activated in reaction to stress,” noted Étienne Vachon-Presseau, a neuropsychology researcher with the University of Montreal. “Our study shows that a small hippocampal volume is associated with higher cortisol levels, which lead to increased vulnerability to pain and could increase the risk of developing pain chronicity."
 

For the study, researchers tracked 16 patients with chronic back pain and compared them to 18 healthy people. They analyzed the relationships between four factors: cortisol levels, levels of reported pain, hippocampal volumes, and brain activity in response to pain.
 

The results showed that patients with a smaller hippocampus have higher cortisol levels and stronger responses to acute pain in the brain region tied to pain-related anxiety.
 

Researchers suggested the findings suggest stress management should be an important element of pain treatment, particularly for chronic sufferers who may be predisposed to feel more pain.
 

"Our research sheds more light on the neurobiological mechanisms of this important relationship between stress and pain,” said lead researcher Pierre Rainville, a university professor of dentistry. “Whether the result of an accident, illness or surgery, pain is often associated with high levels of stress.
 

“Our findings are useful in that they open up avenues for people who suffer from pain to find treatments that may decrease its impact and perhaps even prevent chronicity. To complement their medical treatment, pain sufferers can also work on their stress management and fear of pain by getting help from a psychologist and trying relaxation or meditation techniques."