January 29, 2019
While medications — even as mild as over-the-counter Advil — may seem like the best option, there’s actually a way of reducing pain without popping a pill.
How, you ask? Sleep, that’s how.
New research published in the Journal Neuroscience suggests that another neurological effect of insufficient sleep — in addition to hindering a person’s ability to learn and retain new memories — is heightened sensitivity to pain.
Medical News Today reports that a lack of sleep impairs the brain's natural mechanisms for relieving pain, the new study states, which draws attention to potential links between the public health crises of sleep deprivation, chronic pain and prescription opioid addiction.
For the study, researchers induced pain in 24 healthy, young participants, with no trouble sleeping, by applying heat to their legs. As they were doing so, the scientists scanned their brains, examining the neurological circuits that process pain.
The scientists began by recording each participant's pain threshold after a good night's sleep by scanning their brain with a functional MRI machine while applying increasing levels of pain. Once the participant’s pain threshold was established, they repeated the procedure after a night of no sleep.
"Across the group, [the participants] were feeling discomfort at lower temperatures, which shows that their own sensitivity to pain had increased after inadequate sleep," reports Adam Krause, the study's lead author.
The key thing to note here is that while the afflicted pain is the same, the brain processes it differently with less sleep. The researchers found that the brain's somatosensory cortex, a region associated with pain sensitivity, was hyperactive when the participants hadn't slept enough.
Additionally, researchers were surprised to find that activity in the brain's nucleus accumbens — the area that relieves pain via dopamine — was lower than usual after a sleepless night. "Sleep loss not only amplifies the pain-sensing regions in the brain but blocks the natural analgesia centers, too," the researchers state.
To double-check their findings, researchers also conducted a survey of 230 adults who self-reported their sleep patterns and pain sensitivity over the last few days. From this data, researchers concluded that the slightest change in the participants' sleep patterns resulted in changes in pain sensitivity.
The researchers note that, ironically, the place where people are in the most pain, yet experience the worst sleep is in a noisy hospital. They wrote:
"Our findings suggest that patient care would be markedly improved, and hospital beds cleared sooner, if uninterrupted sleep were embraced as an integral component of healthcare management."