Sensory Feedback Flashcards
What are the two kinds of neuroprostheses?
Sensory and motor neural interfaces
What’s the basic meaning of neuroprostheses, what are the 5 kinds of interfaces?
Link thoughts to movements (and feedback)
*“Brain-to-machine” interfaces (BMIs)
*“Brain-to-body” interfaces (BBIs)
*“Brain-to-machine-to-body” interfaces (BMBIs)
*“Body-to-machine” interfaces (BoMIs)
*“Bidirectional” prostheses
What are the 3 technologies for restoring the sensorimotor loop via bionics
Non-invasive interface
PNS interface
CNS interface
What is proprioception?
To perceive your position in space
What does electrical stimulation do in the axons?
Changes extracellular potential
If the external potential changes at each
node, the internal potential adapts to keep
Vm fixed
What happens if we stimulate the nerve with negative potential?
The node closer to the electrode is at a lower voltage than the others
STRONG inward currents enter the node,
Like with Sodium Channels. Membrane is Depolarized and Action Potentials are triggered
What happens if the nodes have different INTERNAL voltages?
Current flows
What happens if we stimulate the nerve with positive potential?
The node closer to the electrode is at a higher voltage than the others
Half strong inward currents enter the neighbours node, the Membrane is Depolarized in the lateral nodes but less than before
What is better, negative (cathode) or positive (anode) stimulation?
Negative
How does passive damping via fluid systems work, what are the 2 drawbacks?
The piston in a cylinder presses oil or air through a hole, providing speed-dependent damping
Cost and weight
What does an actuated ankle joint do?
Generates joint torque leading to a smooth and powerful push-off
Mimics natural foot motion and increased ground clearance
Give an example of the following:
Passive control
Hybrid control
Control via implantable EMG
Body weight balancing
Smart controller
Mäter EMG i guess
Explain the loop of brain-machine-brain interface
Brain (motor) - decode intent (from signals) - move prosthesis - read sensor output - convert to stimulating pulses - electrically stimulate the brain (somatosensory)
Explain PNS and CSN in the context of neuroprostheses
CNS (Central Nervous System): Includes the brain and spinal cord. It processes and sends out signals to control body functions.
PNS (Peripheral Nervous System): Consists of all the nerves outside the CNS. It transmits signals between the CNS and the rest of the body, including muscles and organs.
The CNS interprets signals and sends commands, while the PNS carries these commands to the prosthesis and relays sensory feedback back to the CNS.
