What are some examples of the sympathetic and parasympathetic systems of the brain?

Example of sympathetic nervous system:

Sympathetic nervous system regulates the functioning of body during fight and flight response.  The example of sympathetic system of brain are increase rate of heart beat, dilation of blood vessels, erection inhibition and loss of hearing. During excitement, emotion and fear the sympathetic nervous system is active.

Example of parasympathetic nervous system:

Parasympathetic nervous system of the brain controls the body function during rest. This system bring the body at normal state after intense fear or excitement. The example of sympathetic system of brain are normal heart beat, constriction of blood vessel and normal erection.

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explanation: