The most common sleep problems in children are difficulty falling asleep and staying asleep and overall insufficient shut-eye.

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According to the National Sleep Foundation's 2004 Sleep in America poll, 13% of school-age children have difficulty falling asleep at bedtime and 26% of preschoolers seem sleepy or overtired during the day at least a few days a week.

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Hyperarousal symptoms include difficulty falling or staying asleep, irritability or outbursts of anger, difficulty concentrating, being hypervigilant and finally, demonstrating an exaggerated startle response.

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