Back pain Back pain Back pain is pain felt in the back. It is divided into neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar area is the most common area for pain, as it supports most of the weight in the upper body. Episodes of back pain may be acute, sub-acute, or chronic depending on the duration. The pain may be characterized as a dull ache, shooting or piercing pain, or a burning sensation. Discomfort can radiate into the arms and hands as well as the
Pain in invertebrates glaber", an unusual rodent species that lacks pain-related neuropeptides (e.g., substance P) in cutaneous sensory fibres, shows a unique and remarkable lack of pain-related behaviours to acid and capsaicin. Similarly, capsaicin triggers nociceptors in some invertebrates, but this substance is not noxious to "Drosophila melanogaster" (the common fruit fly). Criteria that may indicate a potential for experiencing pain include: Brain size does not necessarily equate to complexity of function. Moreover, weight for body-weight, the cephalopod brain is in the same size bracket as the vertebrate brain, smaller than that of birds and mammals, but as big or bigger than most