Pain: A Distributed Brain Information Network?

Understanding how pain is processed in the brain has been an enduring puzzle, because there doesn't appear to be a single ''pain cortex'' that directly codes the subjective perception of pain.An emerging concept is that, instead, pain might emerge from the coordinated activity of an integrated brain network.In support of this view, Woo and colleagues present evidence that distinct brain networks support the subjective changes in pain that result from nociceptive input and self-directed cognitive modulation.This evidence for the sensitivity of distinct neural subsystems to different aspects of pain opens up the way to more formal computational network theories of pain.On the surface, pain should have been one of the easier brain systems to understand.Its fundamental importance in organism defence means that its anatomy should be well conserved across species, unlike systems for language, for instance.And its relatively simple scalar signal (from less pain to more pain) should not require extensive computational processing, unlike sound or vision.However, since Penfield's failure to convincingly locate a ''pain cortex'' during his classic awake brain stimulation studies in the 1950s [1], trying to piece together the pain system in the brain has been a story of frustration and debate.Primers provide a concise introduction into an important aspect of biology highlighted by a current PLOS Biology research article.