12 - Neuroprosthetics Flashcards
1
Q
Neuro/neural prosthesis def
A
- device that bypasses or replaces a missing body function (or svrl) by interfacing the nervous syst via sensing and/or stimulating nerve connections
- output neural interfaces (=BCIs) = extract neural stimuli
- – EEG, MEG, fNIRS, ECoG recordings
- – ctl robotic arms/exoprostheses
- input neural interfaces = stim° of sensory or motor fcts
- – cochlear/retinal implant
- – tactile perception
2
Q
Functional Electrical Stimulation (FES)
A
- muscle stim°
- parameters = current ampl, pulse width and duration, period
- electrodes: surface or implanted
- != stimulation patterns, ideal is 15-25 Hz pulse freq, <1 100 mA current ampl, 100-500 µs duration
- temporal and spatial summation
- pros & cons
- – pros: natural movts, replaces impaired/lost feedback, reduction muscle atrophy and better muscle strength, usable at home
- – cons: fatigue, skin irritation, can be painful, diff placement
- epidural ES = stim the spine
3
Q
Stimulating the brain
A
- non invasive: TMS (transcranial magnc), tDCS (transcranial direct current), tACS (alternating), tPCS (pulsed), tRNS (random noise)
- invasive: DBS
4
Q
Neuroprosthesis challenges
A
- 3 competitive syst = neuroprosthesis ctl, voluntary ctl, spinal reflexes/spasticity
- negative csqces = unsatisfactory fctl gain, time consuming, bad cosmetics
5
Q
Biomechanical modeling
A
- optimisation pb (output error + input error)
- neuromuscular model
- sim°: OpenSim, Segmental Models
- design principles
- – relevant ppts only
- – practical, interpretable, fast/RT model
- – solvable parameter id° procedure
- – /!\ erroneous model components
