Author: Clites, T.R.; Carty, M.J.; Srinivasan, S.; Zorzos, A.N.; Herr, H.M.
Description: OBJECTIVE: Proprioceptive mechanisms play a critical role in both reflexive and volitional lower extremity control. Significant strides have been made in the development of bionic limbs that are capable of bi-directional communication with the peripheral nervous system, but none of these systems have been capable of providing physiologically-relevant muscle-based proprioceptive feedback through natural neural pathways. In this study, we present the agonist-antagonist myoneural interface (AMI), a surgical approach with the capacity to provide graded kinesthetic feedback from a prosthesis through mechanical activation of native mechanoreceptors within residual agonist-antagonist muscle pairs.
APPROACH: (1) Sonomicrometery and electroneurography measurement systems were validated using a servo-based muscle tensioning system. (2) A heuristic controller was implemented to modulate functional electrical stimulation of an agonist muscle, using sonomicrometric measurements of stretch from a mechanically-coupled antagonist muscle as feedback. (3) One AMI was surgically constructed in the hindlimb of each rat. (4) The gastrocnemius-soleus complex of the rat was cycled through a series of ramp-and-hold stretches in two different muscle architectures: native (physiologically-intact) and AMI (modified). Integrated electroneurography from the tibial nerve was compared across the two architectures.
MAIN RESULTS: Correlation between stretch and afferent signal demonstrated that the AMI is capable of provoking graded afferent signals in response to ramp-and-hold stretches, in a manner similar to the native muscle architecture. The response magnitude in the AMI was reduced when compared to the native architecture, likely due to lower stretch amplitudes. The closed-loop control system showed robustness at high stretch magnitudes, with some oscillation at low stretch magnitudes.
SIGNIFICANCE: These results indicate that the AMI has the potential to communicate meaningful kinesthetic feedback from a prosthetic limb by replicating the agonist-antagonist relationships that are fundamental to physiological proprioception.
Subject headings: Extremity control; Bionic limbs
Publication year: 2017
Journal or book title: Journal of Neural Engineering
Volume: 14
Issue: 3
Pages: 036002
Find the full text :Â https://iopscience.iop.org/article/10.1088/1741-2552/aa614b/meta
Find more like this one (cited by): https://scholar.google.com/scholar?cites=5041445003958943762&as_sdt=1000005&sciodt=0,16&hl=en
Type: Journal Article
Serial number: 2095