The American Psychiatric Association will publish a new diagnostic manual in May 2013 and this edition will contain the APA's first major rewrites in 20 years according to the Associated Press. A group of psychiatric board trustees met Saturday outside of Washington, DC to approve the changes.

Perhaps the most notable change: the terminology "Asperger's disorder" will no longer be included. The revised manual will instead include the new term "autism spectrum disorder." According to the AP, this terminology is already seen in the field; what had been recognized as Asperger's will be incorporated under this umbrella diagnosis. Autism spectrum disorder will cover a range of individuals, from mild forms to kids with severe autism who often don't talk or interact with others.

Dr. David Kupfer, chair of the task force in charge of manual revisions and a psychiatry professor at the University of Pittsburgh, told the AP the aim was of the revisions was not to change the number of diagnosed mental illnesses. Rather, he says, the revisions should ensure affected children and adults receive a more accurate diagnosis and then more appropriate treatment.