Dynamic ankle force-matching training associated with subsensory electrical stimulation: cortical and spinal adaptations and effects on postural control

• Grant number: 14/11300-8
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date until: September 01, 2014
• End date until: August 31, 2015
• Field of knowledge: Engineering - Biomedical Engineering - Bioengineering
• Principal Investigator: André Fábio Kohn
• Grantee: Diana Rezende de Toledo
• Supervisor: Albert Gollhofer
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Freiburg, Germany
• Associated to the scholarship: 13/14667-7 - The influence of task type and intensity of muscle contraction in corticomuscular coherence in the control of ankle joint, BP.PD

Abstract

Neurophysiological changes have been associated to motor skill learning. For instance, following ankle force-matching practice, increased corticospinal excitability (assessed by Transcranial Magnetic Stimulation - TMS) and higher interaction between motor cortex and motoneurons (assessed by electroencephalography and electromyography) are observed. However, the corticospinal adaptation after motor skill training is shown to be related to practice duration. Studies have also shown that this practice results in behavioral improvements not only for the trained task at ankle joint, but also for postural control. In addition, such improvements can be potentiated if appropriate levels of mechanical or electrical noise are associated to the motor task. The neurophysiological mechanisms underlying these findings are still unknown. Thus, the aim of this study is to investigate the neural adaptations following dynamic ankle force-matching training by means of H-reflex stimulation, TMS and conditioning of the H-reflex by TMS. These measures will clarify the spinal and corticospinal changes following short- and long-term training. Other factors to be investigated include: behavioral and neurophysiological changes differences between motor training with and without subsensory electrical noise applied over the triceps surae muscles; effects of ankle motor training on balance during postural perturbation; and effect of nerve block on reflexes induced by postural perturbation (investigation of possible training and/or electrical stimulation effects on Ia afferent). This knowledge may result in the development of intervention strategies for rehabilitation and may also assist in the monitoring of neural plasticity resulting from therapeutic interventions and training programs. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TOLEDO, DIANA R.; BARELA, JOSE A.; MANZANO, GILBERTO M.; KOHN, ANDRE F.. Age-related differences in EEG beta activity during an assessment of ankle proprioception. Neuroscience Letters, v. 622, p. 1-5, MAY 27 2016. (09/09286-9, 14/11300-8, 11/17193-0, 13/14667-7)