Neuro 6

Question 1

What is EMG

Answer 1

recording of action potentials occurring in skeletal muscle fibres using extra-cellular recording outside of fibres to record the potential between two locations

Question 2

How to conduct intracellular recording

Answer 2

one electrode inside cell, one outside, measuring voltage between inside and outside of cells

Question 3

How to conduct extracellular recording

Answer 3

both electrodes outside the muscle fibres, measuring voltage between two sites outside the cells

Question 4

What’d does extracellular graph recording look like

Answer 4

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Peak at first electrode causes a voltage deflection, propagation between is at zero, and peak at second electrode causes an opposite voltage deflection

Question 5

What happens when you stimulate during an EMG and no response?

Answer 5

Probably something wrong with setup or not enough stimulation as assessibility of nerve through stimulation is dependant on size

Question 6

What happens when increase the decrease voluntary contraction

Answer 6

as force exerted by muscle increases, EMG amplitude on recording increases . Same for decrease

Question 7

What happens when you have a stronger artificial stimulus

Answer 7

More action potentials and stronger/larger twitch

Question 8

What is tetanus

Answer 8

Tetanus: contraction where twitches are so rapid that they produce a fused tetanic contraction, without distinct contractions

Question 9

What is summation

Answer 9

When increase stimulation, twitches very rapid but can see distinct contract. One twitch start straight after 1 ends

Question 10

Voluntary vs Electrical Stimulation

Answer 10

Voluntarily, we can generate maximal muscle force by sending high frequency of APs to cause fused contraction