Autism spectrum disorder is a term used to include and replace all subtypes of autism, including autistic disorder, Asperger syndrome, childhood disintegrative disorder, and pervasive developmental disorder (not otherwise specified).
The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, published in 2013, defines autism spectrum disorder as follows:
A. persistent deficits in social communication and social interaction across contexts, not accounted for by general developmental delays
B. Restricted, repetitive patterns of behavior, interests, or activities
C. Symptoms must be present in early childhood (but may not become fully manifest until social demands exceed limited capacities)
D. Symptoms together limit and impair everyday functioning.
The 11th edition of the International Classification of Diseases and Related Health Problems, published in 2020, defined autism spectrum disorder as follows:
"Autism spectrum disorder is characterized by persistent deficits in the ability to initiate and to sustain reciprocal social interaction and social communication, and by a range of restricted, repetitive, and inflexible patterns of behaviour and interests. The onset of the disorder occurs during the developmental period, typically in early childhood, but symptoms may not become fully manifest until later, when social demands exceed limited capacities. Deficits are sufficiently severe to cause impairment in personal, family, social, educational, occupational or other important areas of functioning and are usually a pervasive feature of the individual’s functioning observable in all settings, although they may vary according to social, educational, or other context. Individuals along the spectrum exhibit a full range of intellectual functioning and language abilities."
According to the Medical Research Council
'Most researchers believe that ASDs have a variety of causes, perhaps all affecting the same brain systems, or impeding development through disruption of different abilities necessary for social and communicative development.Whether environmental factors interact with genetic susceptibility is as yet unclear.'
Recent studies state that the prevalence of autism cannot be precisely fixed, but it appears to be around 1 in 100 people.
Most forms of autism are present from birth, although the symptoms may not be immediately obvious.
Most forms of autism are more common in boys than in girls.
The 11th edition of the International Classification of Diseases and Related Health Problems, which is due for publication in 2019, notes that
"Autism spectrum disorder is characterized by persistent deficits in the ability to initiate and to sustain reciprocal social interaction and social communication, and by a range of restricted, repetitive, and inflexible patterns of behaviour and interests. The onset of the disorder occurs during the developmental period, typically in early childhood, but symptoms may not become fully manifest until later, when social demands exceed limited capacities. Deficits are sufficiently severe to cause impairment in personal, family, social, educational, occupational or other important areas of functioning and are usually a pervasive feature of the individual’s functioning observable in all settings, although they may vary according to social, educational, or other context. Individuals along the spectrum exhibit a full range of intellectual functioning and language abilities."
It also notes that there are are several sub-types of autism spectrum disorder:
The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders published in 2013 notes that autism spectrum disorder is characterised by:
"A. Persistent deficits in social communication and social interaction across multiple contexts, as manifested by the following, currently or by history :
1. Deficits in social-emotional reciprocity, ranging, for example, from abnormal social approach and failure of normal back-and-forth conversation; to reduced sharing of interests, emotions, or affect; to failure to initiate or respond to social interactions.
2. Deficits in nonverbal communicative behaviors used for social interaction, ranging, for example, from poorly integrated verbal and nonverbal communication; to abnormalities in eye contact and body language or deficits in understanding and use of gestures; to a total lack of facial expressions and nonverbal communication.
3. Deficits in developing, maintaining, and understanding relationships, ranging, for example, from difficulties adjusting behavior to suit various social contexts; to difficulties in sharing imaginative play or in making friends; to absence of interest in peers.
"B. Restricted, repetitive patterns of behavior, interests, or activities, as manifested by at least two of the following, currently or by history:
1. Stereotyped or repetitive motor movements, use of objects, or speech (e.g., simple motor stereotypies, lining up toys or flipping objects, echolalia, idiosyncratic phrases).
2. Insistence on sameness, inflexible adherence to routines, or ritualized patterns or verbal nonverbal behavior (e.g., extreme distress at small changes, difficulties with transitions, rigid thinking patterns, greeting rituals, need to take same route or eat food every day).
3. Highly restricted, fixated interests that are abnormal in intensity or focus (e.g, strong attachment to or preoccupation with unusual objects, excessively circumscribed or perseverative interest).
4. Hyper- or hyporeactivity to sensory input or unusual interests in sensory aspects of the environment (e.g., apparent indifference to pain/temperature, adverse response to specific sounds or textures, excessive smelling or touching of objects, visual fascination with lights or movement).
"C. Symptoms must be present in the early developmental period (but may not become fully manifest until social demands exceed limited capacities, or may be masked by learned strategies in later life).
"D. Symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning.
"E. These disturbances are not better explained by intellectual disability (intellectual developmental disorder) or global developmental delay. Intellectual disability and autism spectrum disorder frequently co-occur; to make comorbid diagnoses of autism spectrum disorder and intellectual disability, social communication should be below that expected for general developmental level."
Each individual will experience these symptoms to a different extent. For example, a child may have little trouble learning to speak but exhibit extremely poor social interaction. Each child will display communication, social, and behavioral patterns that are individual but fit into the overall diagnosis of autism.
Individuals on the autism spectrum, are more likely to have a range of related conditions (comorbidities).
For example, they are more likely to have genetic syndromes (such as Fragile X Syndrome), medical conditions (such as epilepsy) or other developmental disabilities (such as ADHD).
People on the autism spectrum face many issues, including some problems and some challenges, on a day to day basis.
For example, they may find it difficult to communicate with other people or to socialise with them. And they may have additional conditions, such as epilepsy or gastro-intestinal problems, which bring their own issues.
Please see Issues, Problems and Challenges
Individuals on the autism spectrum vary enormously but most will find it hard to cope with other people, to work or to function independently.
Realistically, the majority of children on the autism spectrum can be expected to continue to need some degree of assistance as adults.
In severe form the condition may require intensive, specialised, life long care and support.
Without timely and informed help and support there can be potentially devastating consequences for people with autism and those around them.
An intervention is any kind of activity (such as a treatment, a therapy or the provision of a service) that is designed to improve the quality of life for people on the autism spectrum
There are many different types of intervention and the names and numbers of interventions are increasing all the time.
Some interventions are designed to address the core features of autism (persistent difficulties with social communication and social interaction, along with restricted, repetitive patterns of behaviour, interests, or activities).
Other interventions are designed to address other issues (such as anxiety, aggression or self injurious behaviour).
Some interventions can be quite simple and straightforward. For example, if someone finds a specific situation difficult (such as being in a noisy, crowded room) you can change the situation (by reducing the noise in the room or by not asking the person to be in that room).
Other interventions may be more complex, requiring a team of professional experts and/or expensive materials and implemented over the course of many years.
Unfortunately some interventions are scientifically unfeasible and potentially hazardous. And there is currently very little scientific research to support the use of some interventions despite sometimes extravagant and misleading claims about their effectiveness.
What the research does show is that, while there is no cure for autism, some interventions do appear to help at least some individuals.
However there is no 'one-size fits all' solution. Each person on the autism spectrum is a unique individual, with unique needs and abilities. The most effective interventions follow some key principles, such as being tailored to meet the unique characteristics of each individual.
This section provides a limited selection of studies and reviews on autism which have been published in English-language, peer-reviewed journals within the last 10 years.
You can find more studies and reviews on autism in our publications database.
If you know of any other publications we should list on this page please email info@informationautism.org
Please note that we are unable to supply publications unless we are listed as the publisher. However, if you are a UK resident you may be able to obtain them from your local public library, your college library or direct from the publisher.
This section provides details of other publications on autism
You can find more publications on autism in our publications database.
If you know of any other publications we should list on this page please email info@informationautism.org
Please note that we are unable to supply publications unless we are listed as the publisher. However, if you are a UK resident you may be able to obtain them from your local public library, your college library or direct from the publisher.