An amygdalar neural ensemble that encodes the unpleasantness of pain
One article on PainSci cites Corder 2019: Pain is Weird
PainSci notes on Corder 2019:
Pain is both a sensory and an emotional experience, and it’s notoriously difficult to block the sensation (without tricky trade-offs). So what if you could relieve JUST the unpleasantness of pain? What if you could still detect the noxious stimuli—an important safety feature—but it had no effect on your behaviour? What if you could feel the pain and do it anyway?
Researchers achieved this is in mice by muting a brain region, a "distinct neural ensemble" that encodes the emotional impact of pain.
Perhaps we can do this for humans someday. But that's obviously a long shot. For now it’s mainly just a fascinating demonstration of the duality of the pain experience — which likely exists in all animals.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
Pain is an unpleasant experience. How the brain's affective neural circuits attribute this aversive quality to nociceptive information remains unknown. By means of time-lapse in vivo calcium imaging and neural activity manipulation in freely behaving mice encountering noxious stimuli, we identified a distinct neural ensemble in the basolateral amygdala that encodes the negative affective valence of pain. Silencing this nociceptive ensemble alleviated pain affective-motivational behaviors without altering the detection of noxious stimuli, withdrawal reflexes, anxiety, or reward. Following peripheral nerve injury, innocuous stimuli activated this nociceptive ensemble to drive dysfunctional perceptual changes associated with neuropathic pain, including pain aversion to light touch (allodynia). These results identify the amygdalar representations of noxious stimuli that are functionally required for the negative affective qualities of acute and chronic pain perception.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
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