A chiropractic subluxation often relates to the spine and its connecting structures.1 Chiropractic subluxation assessment generally involves evaluating the pathophysiological consequences of the central segmental motor control problem;4, 12 these may include pain, asymmetry, biomechanical or postural changes (such as changes in relative range of intervertebral motion), changes in tissue temperature, texture and/or tone, and other findings that can be identified using special tests.12Once identified, subluxations are corrected using a variety of techniques including high velocity low amplitude chiropractic adjustments, instrument assisted adjustments, and lower force manual techniques and approaches.13
A growing body of scientific evidence has demonstrated that spinal function impacts central neural function in multiple ways,3, 4, 14-19 and that improving spinal function has an impact on clinical outcomes.20-24 Scientists have known for several decades that neurons continuously adapt in structure and function in response to our ever-changing environment.25-27 This ability to adapt is known as ‘neural plasticity’,27 and it is now well understood that the central nervous system can reorganize in response to altered input.28-35 Examples of increased sensory input that can lead to neural plastic changes include repetitive muscular activity 29, 36-41 such as typing or playing the piano, or repeated tactile sensory input such as occurs with blind Braille readers.42 Similar central nervous system change or reorganization may take place due to a decrease in behavior or activity. 32, 43-49 Thus the concept, that alterations in paraspinal muscle function due to abnormal spinal movement patterns are capable of changing central neural function is totally congruent with current neuroscience understanding, as well as current scientific findings.3, 4, 14-19
 In the scientific literature, this can be known as hyperafferentation. Hyper–meaning increased, and afferentation – meaning the afferent nerves, which are the ones that go to the brain with information.
 In the scientific literature, this is often called deafferentation.
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