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Published on: January 14, 2009
Cortical origin of pathological pain.
1Department of Physiology, University of Otago Medical School, Dunedin, New Zealand. john.harris@stonebow.otago.ac.nz
Lancet (London, England)
|October 30, 1999
Summary
Phantom limb pain and repetitive strain injuries may stem from the brain
Area of Science:
- Neuroscience
- Pain research
- Motor control
Background:
- Pain without apparent tissue damage, like phantom limb pain, is a long-standing medical puzzle.
- Recent discoveries highlight brain activity related to mismatches in sensory and motor signals.
- Conditions like repetitive strain injuries and focal hand dystonias involve changes in the brain's sensorimotor cortex.
Purpose of the Study:
- To explore the neural mechanisms underlying pain perception in the absence of direct tissue injury.
- To investigate the role of sensorimotor cortex and proprioceptive representation in pathological pain.
- To draw parallels between different types of pain and sensory-mismatch conditions.
Main Methods:
- Review of recent neuroscientific findings on cortical activity.
- Analysis of conditions involving sensorimotor cortex plasticity and pain.
- Comparison of pain mechanisms with sensory conflict phenomena like motion sickness.
Main Results:
- A specific cortical region is activated by incongruence between motor intention, movement awareness, and visual feedback.
- Plastic changes in the sensorimotor cortex are associated with phantom limb sensation and repetitive strain injuries.
- Disorganized proprioceptive cortical representation can lead to pathological pain by signaling false motor-sensory mismatches.
Conclusions:
- Pathological pain, including phantom limb pain and repetitive strain injuries, may originate from disorganized cortical processing of sensory information.
- Incongruence in sensory feedback, particularly within the sensorimotor system, is a key factor in generating pain.
- Understanding these brain mechanisms could offer new avenues for treating pain conditions without clear tissue pathology.
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