The prefrontal cortex would store very painful experiences, which could make us more sensitive to a painful sensation felt in a part of the body.
- Fear can both suppress the perception of pain but also reinforce it.
- Frightening memories related to suffering are stored in the prefrontal cortex, the area covering the front part of the mammalian brain.
- This “long-term fear memory” determines whether a painful episode shapes the experience of pain later in life.
Pain and fear are different behavioral states. However, they would be closely linked to each other, according to researchers from the University of Heidelberg (Germany).
Fear can both suppress and reinforce pain
“In the face of danger, fear acutely suppresses the perception of pain, which is essential for survival”they wrote in a study published in the journal Nature Neuroscience. Conversely, when human beings experience severe pain, they may retain a bad memory of it, which causes them to fear situations that they associate with the pain they have felt. These memories can in turn increase their sensitivity to pain or lead to the development of unnecessary behaviors aimed at avoiding that pain. Clear, “A painful episode may lead to an increase in pain experience throughout a person’s lifetime. Fearful anticipation of impending pain could play a role in this phenomenon.”
A neural labeling method and optogenetic techniques
In their work, the scientists sought to better understand which brain regions of mice store very painful experiences and how these stored memories may affect future pain-related experiences. During one experiment, rodents received small electric shocks to their feet and were conditioned to fear receiving those shocks again. The team also used optogenetic techniques to activate or suppress different neural circuits in the mice’s brains to determine how this would affect their sensitivity to pain.
Brain: memories related to pain are stored in the prefrontal cortex
According to the authors, these memories related to suffering are stored “in neural engrams” in the prefrontal cortex, the area covering the front part of the mammalian brain. This “long-term fear memory” determines whether a painful episode shapes the experience of pain later in life.
“These findings reveal that a discrete subset of prefrontal cortex neurons may account for the debilitating comorbidity of fear and chronic pain and show that attenuating pain fear memory can alleviate chronic pain itself. “Our study provides evidence for the decrease in pathological pain through the mastery of anticipatory fear and provides impetus for the development of interventions targeting prefrontal circuits in people with chronic pain and comorbid fear.” explained the scientists in a statement.
