High-functioning autism (HFA) was historically an

autism Autism, also known as autism spectrum disorder (ASD), is a neurodevelopmental disorder characterized by differences or difficulties in social communication and interaction, a preference for predictability and routine, sensory processing d ...

classification to describe a person who exhibited no

intellectual disability Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010).Archive is a generalized neurodevelopmental ...

but otherwise showed autistic traits, such as difficulty in

social interaction A social relation is the fundamental unit of analysis within the social sciences, and describes any voluntary or involuntary interpersonal relationship between two or more conspecifics within and/or between groups. The group can be a language or ...

and

communication Communication is commonly defined as the transmission of information. Its precise definition is disputed and there are disagreements about whether Intention, unintentional or failed transmissions are included and whether communication not onl ...

. The term was often applied to verbal autistic people of at least average intelligence. However, many in medical and autistic communities have called to stop using the term, finding it simplistic and unindicative of the difficulties some autistic people face. HFA has never been included in either the

American Psychiatric Association The American Psychiatric Association (APA) is the main professional organization of psychiatrists and trainee psychiatrists in the United States, and the largest psychiatric organization in the world. It has more than 39,200 members who are in ...

's ''

Diagnostic and Statistical Manual of Mental Disorders The ''Diagnostic and Statistical Manual of Mental Disorders'' (''DSM''; latest edition: ''DSM-5-TR'', published in March 2022) is a publication by the American Psychiatric Association (APA) for the classification of mental disorders using a com ...

'' (DSM) or the

World Health Organization The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Gen ...

's ''

International Classification of Diseases The International Classification of Diseases (ICD) is a globally used medical classification that is used in epidemiology, health management and clinical diagnosis. The ICD is maintained by the World Health Organization (WHO), which is the dir ...

'' (ICD), the two major classification and diagnostic guidelines for

psychiatric Psychiatry is the medical specialty devoted to the diagnosis, treatment, and prevention of deleterious mental conditions. These include matters related to cognition, perceptions, mood, emotion, and behavior. Initial psychiatric assessment of ...

conditions. The DSM-5-TR subtypes autism into three levels based on support needs. Autism Level 1 has the least support needs and corresponds most closely with the "high-functioning" identifier.

Characterization

The term "high-functioning autism" was used in a manner similar to

Asperger syndrome Asperger syndrome (AS), also known as Asperger's syndrome or Asperger's, is a diagnostic label that has historically been used to describe a neurodevelopmental disorder characterized by significant difficulties in social interaction and no ...

, another outdated classification. The defining characteristic recognized by psychologists was a significant delay in the development of early speech and language skills, before the age of three years. The term Asperger syndrome typically excluded a general language delay. Other differences noted in features of high-functioning autism and Asperger syndrome included the following: * Lower verbal reasoning ability * Better visual/spatial skills (Being uniquely artistically talented) * Less deviating locomotion (e.g. clumsiness) * Problems functioning independently * Curiosity and interest for many different things * Not as good at empathizing with other people * Male to female ratio (4:1) much smaller HFA is not a recognised diagnosis by the

or the

. HFA was, however, previously used in clinical settings to describe cases of autism spectrum disorder where indicators suggested an

intelligence quotient An intelligence quotient (IQ) is a total score derived from a set of standardized tests or subtests designed to assess human intelligence. Originally, IQ was a score obtained by dividing a person's mental age score, obtained by administering ...

(IQ) of 70 or greater.

Comorbidities

With the notable exception of

intellectual disabilities Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010).Archive is a generalized neurodevelopmental ...

, which were not part of HFA, cormobidities found in HFA populations reflected those found in autism. (Between 40 and 55% of individuals with autism also have an intellectual disability.) Studies that looked specifically at HFA have examined

anxiety Anxiety is an emotion characterised by an unpleasant state of inner wikt:turmoil, turmoil and includes feelings of dread over Anticipation, anticipated events. Anxiety is different from fear in that fear is defined as the emotional response ...

bipolar disorder Bipolar disorder (BD), previously known as manic depression, is a mental disorder characterized by periods of Depression (mood), depression and periods of abnormally elevated Mood (psychology), mood that each last from days to weeks, and in ...

Tourette syndrome Tourette syndrome (TS), or simply Tourette's, is a common neurodevelopmental disorder that begins in childhood or adolescence. It is characterized by multiple movement (motor) tics and at least one vocal (phonic) tic. Common tics are blinkin ...

attention deficit hyperactivity disorder Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by symptoms of inattention, hyperactivity, impulsivity, and emotional dysregulation that are excessive and pervasive, impairing in multiple con ...

(ADHD), and

obsessive–compulsive disorder Obsessive–compulsive disorder (OCD) is a mental disorder in which an individual has intrusive thoughts (an ''obsession'') and feels the need to perform certain routines (''Compulsive behavior, compulsions'') repeatedly to relieve the dis ...

(OCD). Both HFA and OCD have abnormalities associated with

serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...

Behavior

A 2012 study noted that HFA "disorders are over-represented in the criminal population as compared to the general population," though more research needs to be done in this area. Some case studies have linked the lack of empathy and social naïveté associated with HFA to criminal actions.

Characterization

Comorbidities

Behavior

See also