Many images that is screened on the television sets can be disturbing to young children, warns expert.
According to Marina Krcmar, a communication professor at Wake Forest University, recent research published in the journal Pediatrics shows the TV viewing habits of children aged 3-5 can affect their sleep patterns.
She says characters that look benign can still be scary. For example, children may find the Count on Sesame Street frightening because of his fangs and unusual hair and clothing.
"Any unusual image may be frightening to a preschooler. Whether a character is good or funny is irrelevant," she said.
Small children may also find watching older siblings play video games disturbing.
Krcmar recommends parents to just hug their scared children and not to talk to them.
"It is better to offer physical comfort to young children than to tell them that what they saw on television is make-believe," she said.
"Young children have a hard time distinguishing reality from fantasy until they are about six, so is better to just ensure them they are protected," she added.
The finding has appeared in Journal of Communication, Human Communication Research, and Media Psychology.