psychology-health

As you saw from the analogy in the previous post, brain studies can be made more understandable with the use of simple analogies. Axonal conduction and neurotransmitter activation is also a simple process when it is explained in a logical manner.Consider the following: 

Axonal Conduction:

When a garden tap connected to a hose is left turned on for any length of time without disruption (continual stimulation) the water will run out the end of the hose and into a bucket at the same volume as it went into the hose from the tap (nondecremental nature of action potential conduction). When the hose is turned to the ‘off’ position, the water cannot continue to flow into the bucket, but it also wont go be able to go back up the hose and into the tap (absolute refractory period).If the tap is turned on and off intermittently, the water will only be able to come out of the end of the hose at intervals each time the hose is turned back to the ‘on’ position (intermediate rates of neural firing).When the bucket overflows, the water soaks into the lawn (adjacent voltage-activated sodium channels, which have opened).

Activation of neurotransmitters:

A gentleman places a teabag into a cup with 1/2 an inch of water. The teabag slowly begins to release its flavor into the water (activation of neurotransmitter).A little more water is added, but the teabag does not release any more flavor because the water is cold (inhibitory postsynaptic potential) (membrane is relatively impermeable to sodium ions = cold water)The man decides to add boiling water to the cup instead, and the teabag begins to release its flavor (excitatory postsynaptic potential).After a short while, the teabag stops releasing flavor altogether (action potential has reached its peak), so the man adds a new teabag to the cup of boiling water, and once again the bag begins to release flavor (neuronal firing).