Nyctophobia

Nyctophobia is an irrational dread of darkness.
According to statistics, about 10% of population of our planet is subjected to darkness fear.
There are several reasons why nyctophpbia might be caused.
One of them is our own imagination, because it exists only in our minds.
Surely, night and darkness can constitute a menace for human, especially when you are in remoted area from civilization, where is no lights. In that case it is normal to fear
Another reason is anxious disorder.
The other reason is genetics. If the parents are nyctophoes
The possibility of devolution of the phobia forms 80%.
Mostly, nyctophobia appears at the childhood, then by becoming adult it dissappears or increases.
 Do you usually sleep with dead-headed light?