ADHD is a disorder in which a person displays hyperactive, impulsive, and/or inattentive behaviour that is  inappropriate for their age. To meet the criteria of ADHD, a person must exhibit six or more of the symptoms that fall under the heading of hyperactivity, impulsivity or inattention. These symptoms must interfere with a person's functioning in at least two settings (home /school/ work /social) and symptoms must have been present before the age of 12 years. 

ADHD is the result of an atypical chemical balance in the brain. Childhood symptoms can persist into adolescence and adulthood although the severity of the symptoms may lessen and be noticed more as lack of attention to detail;   distractability or physical restlessness. ADHD has also been identified:

• 1798 - Alexander Crichton - Paper -  Attention and its Diseases.

• 1848 - Heinrich Hoffman - Story books - Fidgety Phil and Johnny Head In The Air.

• 1902 - Dr George Still - Defective Moral Control 

• 1917 - Minimal Brain Dysfunction 

• 1970 -  Attention Deficit Disorder (ADD)

• 1994 -  Attention Deficit Hyperactivity Disorder (ADHD) 

OVERVIEW OF CHANGES TO ATTENTION DEFICIT HYPERACTIVITY DISORDER - ADHD:

The DSM-5 eliminated the DSM-IV chapter that included all diagnoses usually first made in infancy, childhood, or adolescence. 

Attention Deficit Hyperactivity Disorder has moved to a new  “Neurodevelopmental Disorders” chapter to reflect brain developmental correlates with ADHD.
 
The same primary 18 symptoms for ADHD used as in DSM-IV are used in the DSM-5 to diagnose ADHD. They continue to be divided into two major symptom domains: inattention; and hyperactivity/impulsivity and, like in the DSM-IV, at least six symptoms in one domain are required for an ADHD diagnosis for a child. 
 
However, several changes have been made in DSM-5 to the ADHD category:

• Examples have been added to the items to facilitate application across the life span.
   The DSM-5 reflects the differences in ADHD Adults much better than  DSM-IV which  was based on field observations on children only. 

• The cross-situational requirement has been strengthened to “several” symptoms in each setting.

• The age of onset criterion has been changed from “symptoms that caused impairment were present before age 7 years” to “several inattentive or hyperactive-impulsive symptoms were present prior to age 12 years”.      
  (Basically, the age that symptoms first appeared has been raised from age 7 to 12 years).

• Subtypes have been replaced with “presentation specifiers” that are basically same as  prior subtypes  eg “predominantly inattentive presentation”

• A co-morbid diagnosis with autism spectrum disorder is now allowed.

• Most relevant to Adults is the symptom threshold has been lowered  for 17 year olds and older. 

• For an adult diagnosis to be made, the person only needs to meet five symptoms — instead of six required for  
  younger persons — in either of the two major domains: inattention and hyperactivity/impulsivity.

FACT SHEET: http://www.dsm5.org/Documents/ADHD%20Fact%20Sheet.pdf

History of ASD as part of the DSM: The Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychological Association, is the standard for the classification of mental disorders. Giving psychologists a common language and set guidelines for the diagnosis of hundreds of disorders, the DSM has gone through various revisions to compensate for changing times and criteria. Although the DSM is primarily used in the United States, it can also be found in other areas of the world as well. As Autism Spectrum Disorder (ASD) became known throughout the United States and common symptoms and behaviours were agreed upon by many researchers, it gained increasingly specified diagnostic criteria in the DSM. Here, autism is traced throughout the four main revisions of the DSM (Grinker, 2007):
-DSM-I (1952)- Because the idea of autism had recently began circulating, it was not given it’s own diagnostic criteria in this first edition of the DSM. Instead, children demonstrating autistic-like symptoms were classified as ‘childhood schizophrenic’ (American Psychiatric Association, 1952).http://www.psychiatryonline.com/DSMPDF/dsm-i.pdf-DSM-II (1968)- Autism was not included as it’s own diagnostic category in the second release of the DSM. Continuing to be labelled as ‘childhood schizophrenic,’ some of the behaviours fitting the criteria for diagnosis were “autistic, atypical, and withdrawn behaviour” (American Psychiatric Association, 1968, p. 35).http://www.psychiatryonline.com/DSMPDF/dsm-ii.pdf-DSM-III (1980)- Autism is included as a distinct diagnostic category. However, ‘infantile autism’ was designated as the only form and solely 6 characteristics were listed, an individual having to possess each of which to be labelled ‘autistic’ (American Psychiatric Association, 1980).Between the DSM-III and the DSM-III-R criteria for autism, there were some tremendous differences. Diagnostic criteria were more concrete and observable, specifying that such behaviours must reflect abnormalities in the individual’s level of development (American Psychiatric Association, 1987). These changes in the field yielded a rapid increase in the number of individuals being diagnosed with autism (Factor, Freeman, & Kardash, 1989).-DSM-IV (1994)- Following a debate about infantile autism and it’s connotations, several subtypes and a category of pervasive developmental disorders were added. On top of these drastic changes, 16 symptoms were now listed and only six needed to be exhibited in order to be diagnosed with autism. Two of the six symptoms must be based on “qualitative impairment in social interaction,” one based on restricted and repetitive behaviour, and one of qualitative impairment  in communication (American Psychiatric Association, 1994). Examples of other symptoms are a lack of social or emotional reciprocity, stereotyped and repetitive use of language or idiosyncratic language, and persistent preoccupation with parts of objects. While many diagnostic tests are available from ASD specialists and can be received following an investigation and referral by a paediatrician, onset must be prior to the age of three (Grinker, 2007).
-Controversy surrounding the DSM-5: Although Asperger’s Syndrome and Pervasive Developmental Disorder-Not Otherwise Specified have always been considered to be a part of the autism spectrum, they will not be featured in the new edition of the DSM (American Psychiatric Association, 2010). Before, in order to be diagnosed as autistic, an individual would need to demonstrate 2 markers of impairment of social interaction, as well as impairments in communication as well as repetitive and stereotyped behaviours. In the DSM-5, in order to be diagnosed as autistic, an individual must meet all markers of impairment of social interaction and communication, as well as at least 2 signs of repetitive behaviour. Following these new guidelines, an individual who would have previously met the criteria for Asperger’s Syndrome would now be diagnosed under the autism spectrum disorder.

OVERVIEW OF CHANGES TO ASPERGER'S* (ASD)

One of the most important changes in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) is to autism spectrum disorder (ASD). The revised diagnosis represents a new, more accurate, and medically and scientifically useful way of diagnosing individuals with autism-related disorders. 

Using DSM-IV, patients could be diagnosed with four separate disorders:  autistic disorder, Asperger’s disorder, childhood disintegrative disorder, or the catch-all diagnosis of pervasive developmental disorder not otherwise
specified. Researchers found that these separate diagnoses were not consistently applied across different clinics and treatment centres. Anyone diagnosed with one of the four pervasive developmental disorders (PDD) from DSM-IV should still meet the criteria for ASD* in DSM-5 or another, more accurate DSM-5 diagnosis. 

The Neurodevelopmental Work Group,  recommended the DSM-5 criteria for ASD to be a better reflection of the state of knowledge about autism. The Work Group believes a single umbrella disorder will improve the  diagnosis of ASD without limiting the sensitivity of the criteria, or substantially changing the number of children being diagnosed. 

People with ASD tend to have communication deficits, such as responding inappropriately in conversations, misreading nonverbal interactions, or having  difficulty building friendships appropriate to their age. In addition, people with ASD may be overly dependent on routines, highly sensitive to changes in their environment, or intensely focused on inappropriate items. Again, the symptoms of people with ASD will fall on a continuum, with some individuals showing mild symptoms and others having much more severe symptoms. This spectrum will allow clinicians to account for the variations in symptoms and behaviours from person to person. 

Under the DSM-5 criteria, individuals with ASD must show symptoms from early childhood, even if those symptoms are not recognised until later. This criteria change encourages earlier diagnosis of ASD but also allows people whose symptoms may not be fully recognised until social demands exceed their capacity to receive the diagnosis. It is an important change from DSM-IV criteria, which was geared toward identifying school-aged children with autism-related disorders, but not as useful in diagnosing younger children. 

FACT SHEET: http://www.dsm5.org/Documents/Autism%20Spectrum%20Disorder%20Fact%20Sheet.pdf