Voltage-gated Na⁺ channels are balanced off by voltage-gated K⁺ and Cl^- channels

The Na⁺/K⁺ pump is triggered into action to prevent concentration gradients being lost

Of the Relative Refractory Period

Voltage-gated Na⁺ channels become refractory rapidly after opening

Voltage-gated K⁺ channels open

Our electrodes are not placed to record trans-membrane currents/voltages

Our filters are not appropriate

The ground electrode shorts all APs to ground

Cockroach neurons dont have APs

We have not amplified enough

the ulnar nerve has a larger diameter from elbow to wrist than from wrist to hand

of the longer length of nerve for the elbow stimulation

of not correcting for the same fixed neuromuscular junction delay

you are stimulating the fast ulnar at the elbow and the slow hypothenar at the wrist

the ulnar is myelinated from elbow to wrist but not from wrist to hand

Muscle fibres

A spinal nerve consisting of sensory and motor axons

A single sensory neuron

A single afferent neuron

A spinal nerve consisting of an afferent and an efferent neuron

is produced when the membrane potential is depolarized to 0 mV.

is the result of a transient increase in K⁺ permeability and Cl^- permeability.

is the result of a transient increase in Na⁺ permeability and a decrease in K⁺ permeability.

is associated with an increase in the electrical resistance of the nerve membrane.

is always of a fixed size regardless of the strength of the stimuli eliciting the action potential.

An unmyelinated, small diameter nerve

A myelinated, small diameter nerve

They would all have the same conduction velocity

A myelinated, large diameter nerve

An unmyelinated, large diameter nerve

Cockroach neurons are small 

Neurons are noisy structures

Cockroach neurons are not myelinated

The "X Files" is correct and we are actually being targeted by aliens

There is stray electrical noise from electrical equipment

6-7 msec

1-2 msec

0.5 msec

5 msec

1 sec