If you’re in pain, try getting a good night’s sleep. New research indicates that sleep deprivation numbs the brain’s ability to kill pain, increasing your sensitivity.
Determining pain threshold
A team from the University of California in Berkeley carried out research on 24 healthy young adults who had no pain-related disorders or trouble sleeping.
They recorded the volunteers’ pain threshold after plenty of sleep using fMRIs, then applied heat to the participants’ legs at increasing levels until they reached each person’s pain threshold. Then, they did it all again after the volunteers stayed up all night.
The results after no sleep
The team found that when the volunteers hadn’t gotten any sleep, the part of the brain associated with pain sensitivity was hyperactive.
In addition, they found that after a night with no sleep, the nucleus accumbens, which releases dopamine to increase pleasure and relieve pain, had less activity than usual.
To make matters worse, the team discovered that the insula, the part of the brain that assesses pain signals and get the body prepared to react, was underactive after the all-nighter.
So, after a sleepless night, the participants had three factors working against them: the pain-sensing region of the brain was amplified. the part that serves as a natural analgesia was blocked and the part of the brain that prepared the body to react to pain was underactive.
“Across the group, [the participants] were feeling discomfort at lower temperatures, which shows that their own sensitivity to pain had increased after inadequate sleep,” says the study’s lead author, Adam Krause. “The injury is the same, but the difference is how the brain assesses the pain without sufficient sleep.”
More proof
The researchers also surveyed more than 230 adults to ask about pain sensitivity levels and sleep patterns. They found that even small changes in sleep were linked to changes in pain sensitivity.
