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Brain mechanisms of chronic pain: critical role of translational approach

  • Author Footnotes
    # All the authors contributed equally to this work.
    Joana Barroso
    Footnotes
    # All the authors contributed equally to this work.
    Affiliations
    Department of Physiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois

    Department of Physical Medicine and Rehabilitation, Northwestern University, Feinberg School of Medicine, Chicago, Illinois

    Center for Chronic Pain and Drug Abuse, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
    Search for articles by this author
  • Author Footnotes
    # All the authors contributed equally to this work.
    Paulo Branco
    Footnotes
    # All the authors contributed equally to this work.
    Affiliations
    Department of Physiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois

    Center for Chronic Pain and Drug Abuse, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
    Search for articles by this author
  • Author Footnotes
    # All the authors contributed equally to this work.
    Apkar Vania Apkarian
    Correspondence
    Reprint requests: Apkar Vania Apkarian, Northwestern University, Feinberg School of Medicine, Tarry Bldg. 7-705, Chicago, IL 60611;
    Footnotes
    # All the authors contributed equally to this work.
    Affiliations
    Department of Physiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois

    Department of Physical Medicine and Rehabilitation, Northwestern University, Feinberg School of Medicine, Chicago, Illinois

    Center for Chronic Pain and Drug Abuse, Northwestern University, Feinberg School of Medicine, Chicago, Illinois

    Department of Anesthesiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
    Search for articles by this author
  • Author Footnotes
    # All the authors contributed equally to this work.
      Chronic pain is a leading cause of disability worldwide and its prevalence is likely to increase over the next decades. Treatment for chronic pain remains insufficient and therapeutical advances have not made comparable progress with that for many chronic disorders, thus amplifying the concern on the future burden of the disease. At the same time, and even after decades of intense research, the underlying pathophysiology of chronic pain remains minimally understood. We believe advancing our current understanding of chronic pain requires mechanistically explicit, hypothesis-driven, and clinically focused models. In this review we highlight some of the main findings over the last decades that have contributed to the present knowledge of brain mechanisms of chronic pain, and how such advances were possible due to a reverse translational research approach. We argue that this approach is essential in the chronic pain field, in order to generate new scientific hypotheses, probe physiological mechanisms, develop therapeutic strategies and translate findings back into promising human clinical trials.

      Abbreviations:

      CBP (chronic back pain), DLPFC (dorsolateral prefrontal cortex), mPFC (medial prefrontal cortex), NAc (nucleus accumbens), PFC (prefrontal cortex), OA (osteoarthritis), SNI (spared-nerve injury)
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