title: Neural substrates for the motivational regulation of motor recovery after spinal-cord injury.
abstract: It is believed that depression impedes and motivation enhances functional recovery after neuronal damage such as spinal-cord injury and stroke. However, the neuronal substrate underlying such psychological effects on functional recovery remains unclear. A longitudinal study of brain activation in the non-human primate model of partial spinal-cord injury using positron emission tomography (PET) revealed a contribution of the primary motor cortex (M1) to the recovery of finger dexterity through the rehabilitative training. Here, we show that activity of the ventral striatum, including the nucleus accumbens (NAc), which plays a critical role in processing of motivation, increased and its functional connectivity with M1 emerged and was progressively strengthened during the recovery. In addition, functional connectivities among M1, the ventral striatum and other structures belonging to neural circuits for processing motivation, such as the orbitofrontal cortex, anterior cingulate cortex and pedunculopontine tegmental nucleus were also strengthened during the recovery. These results give clues to the neuronal substrate for motivational regulation of motor learning required for functional recovery after spinal-cord injury.
authors.affiliation: Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Japan. yukio@nips.ac.jp
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Onoe
authors.forename: Kayo
authors.initials: K
authors.lastname: Onoe
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Morichika
authors.forename: Hideo
authors.initials: H
authors.lastname: Tsukada
authors.forename: Tadashi
authors.initials: T
authors.lastname: Isa
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D004195:Disease Models, Animal; D005260:Female; D008251:Macaca; D008253:Macaca mulatta; D008297:Male; D008954:Models, Biological; D015233:Models, Statistical; D009042:Motivation; D009044:Motor Cortex; D009048:Motor Skills; D009474:Neurons / Q000378:metabolism / Q000473:pathology*; D009714:Nucleus Accumbens / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods; D013119:Spinal Cord Injuries / Q000534:rehabilitation*