How do neurons communicate?

Neurons are like electrical wires, but ‘intelligent’ wires. The gap between the neurons are called synapse (see pic). One neuron talk to the next neuron through a series of chemicals called ‘neurotransmitters’ which travel across the synapse.

When a nerve is excited, the electrical activity causes the nerve endings to secrete neurotransmitter chemicals which act on the next neuron. After the impulse pass, the neurotransmitter is recycled back to be ready for the next firing; that’s the reason why after doing 20 sit-ups you have to stop, take rest and let these chemical re-accumulate (BTW, the reason behind muscle fatigue is far more complex).

Neurotransmitters like ‘adrenalin’ are for flight and fright, ‘Dopamine’ for motor movement, ‘serotonin’ for mood stabilization, ‘acetyl choline’ for muscle contraction and so on.

But the cross-talk between neurons of a human brain is far more complex than the wiring system of any electrical machine. In an electrical equipment (say an aircraft) one set of wiring is dedicated to one function; but not in human nervous system. The same set of neurons do multitasking depending on the situation encountered.

Varied diseases from ‘parkinsonism’ to ‘alzheimers’, traits from ‘depression’ to ‘ADHD’ has been ascribed to subtle change of micro molar concentration of neurotransmitters.

Neurologically, the difference between a ‘respectable-academician-scholar’ and a ‘psychopathic criminal’ is just nano-molar concentration of a rare chemical cross-talking between two neurons !!

Reference: Tiny Nair