High-functioning autism

# Overview
High-functioning autism (HFA) is an informal term applied to individuals with autism, an IQ of 80 or above, and the ability to speak, read, and write. HFA may simply refer to autistic people who have normal overall intelligence; that is, are not cognitively challenged.

# Developing clinical label
Care should be exercised when attempting to determine whether a person with autism is "high functioning" or "low functioning" based on an IQ score since it is sometimes difficult to measure IQ in autistic persons accurately using standard measurement instruments.  The amount of language processing necessary on the tests and the large quantity of verbal instructions involved in the testing process even on the "non-verbal" portion of standard intelligence measures can produce a misleadingly low score.  There can be a significant difference between an autistic person's measured IQ scores when comparing standard testing methods and a truly non-verbal method such as the Leiter-R.  
A diagnosis of high-functioning autism exists in neither the DSM-IV-TR nor the ICD-10, which have diagnoses of autistic disorder and childhood autism respectively. Analogous to high-functioning when applied to schizophrenia and other psychiatric disorders, the term high-functioning autism started out as a shorthand to describe diagnosed autistic individuals who could nevertheless speak and carry on with many day-to-day activities like eating and dressing independently. Low-functioning autism was the conceptual opposite. Researchers then began using high-functioning autism as a quasi-diagnostic label itself, along with low-functioning autism and sometimes also Asperger's Syndrome, to distinguish relative levels of adaptation and development.
There is some evidence that the label has wrongly become a catch-all diagnosis for badly-behaved children. In 2000 in the UK, the lead clinician and autism specialist at Northgate and Prudhoe NHS Trust in Morpeth, Dr Tom Berney, published a paper commenting on this. He wrote in the prestigious British Journal of Psychiatry:- "There is a risk of the diagnosis of autism being extended to include anyone whose odd and troublesome personality does not readily fit some other category. Such over-inclusion is likely to devalue the diagnosis to a meaningless label."

# Social aspects
Autistic people are prone to commit social faux pas because of an inability to predict others' reactions. They may also neglect social niceties like knocking or returning a greeting.  Similarly, they may be overly trusting or paranoid of strangers. It may be best summed up as an inability to understand/perceive the intent or emotional wants and needs of others around them.
They may appear somewhat removed or dissociated or dreamy at times, especially when in sensory overload or from a perception of extreme social pressure. They may make little eye contact, leading others to conclude that they are shy, uninterested or evasive.
Unlike those with low-functioning autism, people with high-functioning autism are not mentally retarded; persons with high-functioning autism have an IQ at the average to above-average range. Although they may have an adequate vocabulary, they may have a delay in communicating events and use less emotional content in their speech. They may also appear not to notice non-verbal cues from others such as when others have become bored with the topic of conversation they appear oblivious and continue.
As with people elsewhere on the autistic spectrum, people with high-functioning autism generally prefer routine and order, and this usually begins in early childhood. They may, for example, write an alphabetized index of their comic book collection, or they may stick to a limited wardrobe.

# Associated difficulties
Generally, there are difficulties with social interaction. This might not adversely affect their ability to interact with others on a day-to-day basis at a basic working level, although they may be seen as being overly serious or earnest, and as being without any "small talk" in conversation.  In many instances though, these individuals have such severe social delays and difficulties that interaction within a "normal" social setting can be severely hampered.
They may have difficulty initiating love and friendship relationships, often being rejected because potential partners perceive them as being either too "nerdy" or too intelligent. This can lead to low self esteem or loneliness, which further impairs their ability to find meaningful companionship.
People may label HFA people as "oddballs" or worse, and HFA people can easily become the target of bullying. This can be especially true from primary school through the late teens. Young, intelligent HFA people usually do best by seeking out the company of their intellectual peers or by joining hobby groups, while avoiding their age-group peers.  Exposure to an age equivalent peer group within the autism spectrum on a regular basis can be especially beneficial.
Given the proven crucial role of body language in job interviews, lack of eye contact in such a situation may be perceived by potential employers as indicating that the candidate is "not telling the truth" or "uninterested in the job", and thus lead to a cumulative difficulty in finding employment. Attending social and business events to network is also proven to play a crucial role in job hunting, but events such as these are the type that HFA people usually avoid due to their unease with the complex social interactions required. Difficulties with such pre-employment factors may contribute to comparative poverty, although intelligent HFA adults can usually find a good job if they can specialise in their area of interest. Once in a good job, however, their talents may lead to promotion and they may find themselves in a new job description that does not fit their personality.
Some may have minor to moderate difficulty with motor skills and co-ordination.  This may manifest itself as mere clumsiness or awkwardness but in some instances can be found at a level where the child is a danger to themselves (this is especially true when younger), but may manifest itself in adulthood by "bumping into walls" and doors or other people without intention. "Sensory motor dysfunction" is a comorbid diagnosis that is increasingly being associated with individuals with HFA.  Many of these motor skills and functional issues can be helped through the use of regular physical therapy.
Some may also nurture a complex habitual movement (termed "stimming") at which they become adept, for example, pen spinning, while otherwise being prone to clumsiness.
They do not lack empathy (although they may have difficulty expressing it), and can thus enjoy films and stories with emotional content. Some may gain the bulk of their insight into why people behave the way they do through watching movies that provide a forceful and musically-cued "capsule lesson" in human emotions (e.g. melodramas).

# Benefits
Alongside deficiencies they may simultaneously benefit from some of the more positive aspects of autism. For example, they may have the ability to focus intensely and for long periods on a difficult problem. There is often an enhanced learning ability, although this often is not applied to subjects they are uninterested in. They often present no problems in a supportive, well-resourced educational institution and often do well academically if they can be stimulated by good teachers.  People with HFA often have intense and deep knowledge of an obscure or difficult subject and a passion for pursuing it in an organized and scholarly manner.
They are usually intelligent, gifted, honest, hard workers when interested in a task and excellent problem solvers. People with HFA are thought to become excellent scientists and engineers or enter other professions where painstaking, methodical analysis is required.  Some believe this particular assertion is a stereotype, as some HFA adults tend to struggle with the traditional work setting and the surrounding societally accepted ways of behaving.
Speech and diction can be unusually precise in some individuals with HFA but this may be delayed or awkward in many other individuals.

# Gender differences
HFA affects far more males than females. The ASD sex ratio, which averages 4.3:1, is greatly modified by cognitive impairment: it may be close to 2:1 with mental retardation and more than 5.5:1 for HFA.

# Prevalence
In the 1990s the prevalence was assumed to be about 1 person per 2,000 in England. However, a study published in The Lancet medical journal in July 2006 reported that a team at a hospital in London had applied autism tests to a large number of children aged 9 to 10. They found 39 of 10,000 children had autism, and 77 of 10,000 had some form of "autism spectrum disorders" (i.e.: a ratio of about 1 in 130 people). The apparent rise may be due to better diagnosis, and to better awareness of autism related disorders in people without learning disabilities.