A young boy uses a tablet computer. This week Facebook announced plans to open their site to children under the age of 13. - 

How young is too young to be on Facebook? In order to increase its reach, Facebook is now developing a system that would allow children under the age of 13 to play games and use the social network. Until now, that age group has been barred from the site. Child advocates and some psychologists are raising privacy and developmental concerns.

For our Mid-day extra, we talked to psychologist and editor in chief of Pysch Central, Dr. John Grohol about the lack of psychological research in this area and how kids are likely to use the site.

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