The Brain Is Needed to Cure Spinal Cord Injury. Issue 10 (October 2017)

• Record Type: Journal Article
• Authors: Isa, Tadashi
• Is Part Of: Trends in neurosciences. Volume 40:Issue 10(2017)
• Page Start: 625
• Page End: 636
• Publication Date: 2017-10
• Subjects: recovery -- hand dexterity -- corticospinal tract -- propriospinal neuron -- nucleus accumbens -- primates; Neurology -- Periodicals; Neurophysiology -- Periodicals; Neurobiology -- Periodicals; 612.8
• DOI: 10.1016/j.tins.2017.08.002
• Languages: English
• ISSNs: 0166-2236

Abstract

Abstract : Damage to corticospinal fibers in the cervical spinal cord is known to impair dexterous hand movements. However, accumulating evidence has shown that precision grip can recover considerably through rehabilitative training. Recent multidisciplinary studies have revealed that, at the spinal level, this recovery is possible due to an indirect neural pathway through propriospinal neurons (PNs), which relay cortical commands to hand motoneurons. Although this indirect spinal pathway is heavily involved in recovery, its role is dwarfed by a simultaneous large-scale network reorganization spanning motor-related cortices and mesolimbic structures. This large-scale network reorganization is key to the regulation of recovery and future therapeutic strategies will need to take into account the involvement of these supraspinal centers in addition to the known role of the spinal cord. Trends: Many studies have focused on molecular biological approaches to cure spinal cord injury, such as stem cell and pharmacological therapies. These approaches are generally nonselective treatments of impaired neural functions. In recent years neural mechanisms of functional recovery after spinal cord injury have become better understood. These discoveries now allow the development of novel therapeutic strategies targeting particular neural circuits to promote recovery. Experimental studies on nonhuman primate models are particularly important in this context, because the structure and function of their motor circuits and body plans are similar to those of humans. Multidisciplinary approaches, most importantly those selectively targeting regions via pharmacological agents or viral vectors, have started to identify the neuronal mechanism of recovery. Reorganization during recovery appears to occur in multiple areas of the CNS.