Spindle fibers are protein structures that form early in mitosis, or cell division. They consist of microtubules that originate from the centrioles, two wheel-shaped bodies located in the centromere area of the cell. The centromere is also known as the microtubule organizing center.
1 Night terrors are characterized by frequent recurrent episodes of intense crying and fear during sleep, with difficulty arousing the child. Night terrors are frightening episodes that disrupt family life.  A small percentage of children experience night terrors.
Night terrors have been shown to appear in stage 4 of sleep. This is just one thing that separates them from nightmares which can occur anytime in sleep. It is possible to make a night terror occur in some people, simply by touching or awakening them during stage 4 of sleep.lthough night terrors can occur anytime in a persons life span, the most common is reported in children between the ages of three and five.