ISEK 2024 - Day 2

Keynote speech: Catherine Diselhorst-klug (university fo Aachen)

What are my muscles up to?

The entire pipeline from electrodes to signal processing and clinical application

• how does the body manage to perform movvements at suc ahigh degree of freedom?
  • AP from brain to SC to MN to muscle fibers and introduce mechanical coupling then force…to control posture and coordinate movementthere is afeedback loop back to the brain.
  • this sounds like chaos? how to control this chaos?
    • trial and error principle this is how motor developement takes place. this way infants train their neuronal netowrk
    • motor learning and developement: the first month of lide related to spontaneous movements. Infants learn by playing; they learn range of motions. This way neuronal netowrks are trained and corrdination start to emerge
    • However there are cases of abnormal motor developement (eg infantile cerbral palsy)
• Organization of motor control
  • suprapsnal centers
  • proprioceptive feedback back to interneurons
  • • movemtn to brain directly exteroceptive feedback
  • • feebakc from env. conditions
• How does CNS control muscle force?
  • motoneurons: can be investigated with needle EMG (used in clinical diagnosis up to now, gives infor about single MUs)
    • another way is HDemg (from 3o years back),
      • and applying laplacian filters (a spatial filter), the peaks of MUAP are observed (1998)
    • with eelectrode arrays: if we plcae them paralley to MU and muscle fibers, we can get a spatially filtered signa of the MUAP travelling on the fibers.
      • we can then quantify conduction velocity
      • Campanini al 2022, sensors
• Pathological changes to MU excitation: she is interested in Differences between lower and upper motor neuron disorder
  • Study to investigate MU activation in spasticity
    • upper Mn disorder spacitity, they observe regular firing around 8 Hz.
  • We can diagnose neuromuscular disorder using non-invasive
• how are muscles activiated correctly to excete movement (Coordination):
  • kinesiology sEMG (measuremet of sEMG with info about movememt)
  • Muscle co-contraction
    • In healthy subejcts there is a coordinated activation of antagonist muscles
    • In patients with ICP, co-activation of muscles or reduced primitive synerfies are often interpresd as spasticity (velocity-dependent increase in the tonic stretch reflex)
  • They are intererseted in dsitinguishing spasticity from voluntary activation
• Assistive technologies for rehabilitation. To autonomisly retrain the nervous system
  • inRehaRob