Autism

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Autism is classified by the World Health Organization and American Psychological Association as a developmental disability that results from a disorder of the human central nervous system. It is diagnosed by impairments to social interaction, communication, interests, imagination and activities. However, the causes, symptoms, etiology, treatment and other issues are controversial.

Autism manifests itself at a very early age, "before the age of three years" according to the World Health Organization's International Classification of Diseases (ICD-10)[1] Autistic children are marked by delays in their "social interaction, language as used in social communication, or symbolic or imaginative play" (Diagnostic and Statistical Manual of Mental Disorders).[2]

Autism, and the other four pervasive developmental disorders (PDD), are all considered to be neurodevelopmental disorders. They are diagnosed on the basis of a triad, or group of three behavioral impairments or dysfunctions: 1. impaired social interaction, 2. impaired communication and 3. restricted and repetitive interests and activities.[3] These three basic characteristics reflect Dr. Leo Kanner's first reports of autism emphasizing "autistic aloneness" and "insistence on sameness".

From a physiological standpoint, autism is often less than obvious in that outward appearance may not indicate a disorder. Diagnosis typically comes from a complete physical and neurological evaluation.

The incidence of diagnosed autism has increased since the 1990s. [4] Reasons offered for this phenomenon include better diagnosis, wider public awareness of the condition, regional variations in diagnostic criteria, or simply an increase in the occurrence of ASD (autism spectrum disorders). The United States Centers for Disease Control (CDC) estimate the prevalence of autism spectrum disorders to be about one in every 150 children.[5][6] In 2005, the National Institute of Mental Health (NIMH) stated the "best conservative estimate" as 1 in 1000.[7]. In 2006, NIMH estimated that the incidence was 2-6 in every 1000 [8]

There are numerous theories as to the specific causes of autism, but they are as yet unproven (see section on "Causes" below). Proposed factors include genetic influence, anatomical variations (e.g. head circumference), abnormal blood vessel function and oxidative stress. Their significance as well as implications for treatment remain speculative.

Conversely, some autistic children and adults are opposed to attempts to cure autism. These people see autism as part of who they are, [9][10][11] and in some cases they perceive treatments and attempts of a cure to be unethical.[12]

Contents

Terminology

This article uses both "autistic people" (or "autistic person") and "people with autism" (See section below in "Sociology" for "Terminology").

History

Dr. Leo Kanner introduced the label early infantile autism in 1943.

The word "autism" was first used in the English language by Swiss psychiatrist Eugene Bleuler in a 1912 issue of the American Journal of Insanity. It comes from the Greek word for "self," αυτος (autos).[13] Autism was actually confused with schizophrenia during the early stages of observation.[14] Bleuler used the term to describe the schizophrenics' seeming difficulty in connecting with other people.[15]

However, the classification of autism as a separate disorder or disease did not occur until 1943 when psychiatrist Dr. Leo Kanner of the Johns Hopkins Hospital in Baltimore reported on 11 child patients with striking behavioral similarities and introduced the label "early infantile autism."[16] He suggested the term "autism" to describe the fact that the children seemed to lack interest in other people. Kanner's first paper on the subject was published in a now defunct journal called The Nervous Child,[17] and almost every characteristic he originally described is still regarded as typical of the autistic spectrum of disorders.[18]

At the same time, an Austrian scientist named Dr. Hans Asperger made similar observations, although his name has since become attached to a different higher-functioning form of autism known as Asperger syndrome. Widespread recognition of Asperger's work was delayed by World War II in Germany, and by his seminal paper not being translated into English for almost 50 years. The majority of his work was not widely read until 1997.[19]

Autism and Asperger's Syndrome are today listed in the DSM-IV-TR as two of the five pervasive developmental disorders (PDD), which also include Childhood disintegrative disorder, Rett syndrome and Pervasive Developmental Disorder Not Otherwise Specified (or atypical autism). Health care providers also refer to autism spectrum disorders (ASD) which includes only three of those listed in PDD: Autistic disorder, Asperger syndrome, Pervasive Developmental Disorder Not Otherwise Specified.[20] All of these conditions are characterized by varying degrees of deficiencies in communication skills and social interactions, along with restricted, repetitive, and stereotyped patterns of behavior.

Characteristics

On the surface, individuals who have autism are physically indistinguishable from those without. Sometimes autism co-occurs with other disorders, and in those cases outward differences may be apparent.

Individuals diagnosed with autism can vary greatly in skills and behaviors, and their response to sensory input shows marked differences in a number of ways from that of other people. Certain stimulations, such as sounds, lights, and touch, will often affect someone with autism differently than someone without, and the degree to which the sensory system is affected can vary greatly from one individual to another. [21]

Autistic children may display or fail to display certain behaviors. In assessing developmental delays, different physicians may not always arrive at the same conclusions. Much of this is due to the disputed diagnostic criteria for autism, paired with the difficulty in constructing objective diagnostic tests. Nevertheless, professionals within pediatrics, child psychology, behavior analysis, and child development are always looking for early indicators of autism.

Key Behaviors

Some behaviors cited by the National Institute of Child Health and Human Development and listed below may simply mean a normal delay in one or more areas of development, while others are more typical of ASDs—Autistic Spectrum Disorders.[22]

Noted behaviors

  • does not respond to his/her name.
  • cannot explain what he/she wants.
  • language skills are slow to develop or speech is delayed.
  • doesn't follow directions.
  • at times, the child seems to be deaf.
  • seems to hear sometimes, but not other times.
  • doesn't point or wave "bye-bye."
  • used to say a few words or babble, but now he/she doesn't.
  • throws intense or violent tantrums.
  • has odd movement patterns.
  • is overly active, uncooperative, or resistant.
  • doesn't know how to play with toys.
  • doesn't smile when smiled at.
  • has poor eye contact.
  • gets "stuck" doing the same things over and over and can't move on to other things.
  • seems to prefer to play alone.
  • gets things for him/herself only.
  • is very independent for his/her age.
  • does things "early" compared to other children.
  • seems to be in his/her "own world."
  • seems to tune people out.
  • is not interested in other children.
  • walks on his/her toes.
  • shows unusual attachments to toys, objects, or schedules (i.e., always holding a string or having to put socks on before pants).
  • spends a lot of time lining things up or putting things in a certain order.

Physically people with autism are typical in appearance. Some studies show that autistic children tend to have larger head circumferences[23][24] but the significance in the disorder is unclear.

Social development

Typically, developing infants are social beings -- early in life they gaze at people, turn toward voices, grasp at fingers, and smile. In contrast, most autistic children do not show special interest in faces and seem to have tremendous difficulty learning to engage in everyday human interaction. Even in the first few months of life, many autistic children seem indifferent to other people, lacking the eye contact and interaction with others that non-autistic children exhibit naturally. Some infants with autism may appear very calm; they may cry less often because they do not seek parental attention or ministration. For other children with autism, infantile development progresses normally through language acquisition. Between 18 months and 2 years, however, skills previously mastered disappear, including language and social skills.

Autistic children often seem to prefer being alone and may passively accept such things as hugs and cuddling without reciprocating, or resist attention altogether. Later, they seldom seek comfort from others or respond to parents' displays of anger or affection in a typical way. Research has suggested that, despite popular belief, autistic children are attached to their parents. Although this may be difficult for others to pick up because their particular ways of expressing this attachment may differ from the patterns of expression used by their typical peers.[25] Though social deficits are common, autistic children may vary significantly in their levels of social attachment and interaction.

According to Simon Baron-Cohen et al (1985),[26] many autistic children appear to lack a "theory of mind". Theory of mind refers to representing epistemic mental states such as knowing, believing, deceiving or imagining, and tying them together "into a coherent understanding of how mental states and actions are related."[27] This is a behavior cited as being exclusive to human beings above the age of five and possibly, to a lesser degree, to other higher primates such as adult gorillas, chimpanzees and bonobos.[28] Typical 5-year-olds can usually develop insights into other people's knowledge, feelings, and intentions based on social cues (e.g., gestures, vocal tone and facial expressions). An autistic individual may lack these interpretation skills, leaving them unable to predict or understand other people's actions or intentions.

Many children with autism experience social alienation during their school-age years. As a response to this, or perhaps because their social surroundings simply do not "fit" them, many report inventing imaginary friends, worlds, or scenarios.[29] Making friends in real life and maintaining those friendships often proves to be difficult for those with autism.

Although not universal, behavioral lability may be common, resulting in crying, verbal outbursts, or self-injurious behaviors that seem inappropriate or without cause. Those who have autism may benefit from consistent routines and environments, and they may react negatively to changes in their surroundings. It is not uncommon for these individuals to exhibit poorly modulated behaviors, increased levels of self-stimulatory behavior, self-injury, or extensive withdrawal in overwhelming situations. However, as an affected individual matures and receives specific socialization education and training, skill may be attained in the recognition of behavioral triggers and more appropriate means of coping will be available for difficult social circumstances.

Sensory system

Indicators of autism include oversensitivity or under reactivity to touch, movement, sights, or sounds; physical clumsiness or carelessness; poor body awareness; a tendency to be easily distracted; impulsive physical or verbal behavior; an activity level that is unusually high or low; not unwinding or calming oneself; difficulty learning new movements; difficulty in making transitions from one situation to another; social and/or emotional problems; delays in speech, language or motor skills; specific learning difficulties/delays in academic achievement. However, it is important to remember that while most people with autism have some degree of sensory integration difficulty, not every person who has sensory problems is autistic.

Autistic individuals may sometimes also develop obsessions or routines around foods, restricting what is eaten to certain colors, textures or types of food; alternatively they may obsessively avoid certain foods with similar characteristics.[30]

One common example is autistic hearing. An autistic person may have trouble hearing certain people while other people are perceived as speaking at a higher volume. Or the autistic may be unable to filter out sounds in certain situations, such as in a large crowd of people. However, this is perhaps a part of autism that tends to vary widely from person to person, so these examples may not apply to every autistic person. Note that such auditory difficulties fall under auditory processing disorders, and like sensory integration dysfunction, are not necessarily experienced by all people with autism or indicative of a diagnosis of autism.

Autism and blindness

The characteristics of a person with both an Autism Spectrum Disorder (ASD) and a severe visual impairment (VI) may vary from a person with just ASD or just VI.[31] Historically, many behaviors of blind children were seen as "autistic-like" but were attributed to their blindness rather than pursuing possibilities of autism.[32]

Developmental trajectories of children with ASD-VI are often very similar as those followed by children with typical autism, but the child with ASD-VI will have particularly unusual responses to sensory information. The person may be overly sensitive to touch or sound, or be less responsive to pain. Typically, touch, smell, and sound are affected the most dramatically.[33]

Communication difficulties

Some people with high-functioning autism demonstrate advanced cognitive ability, but lack the skills or are not inclined to interact with others socially. An example of this is the noted autistic Temple Grandin, who holds a PhD and is a successful developer of livestock handling technologies. She describes her inability to understand the social communication of neurotypicals as leaving her feeling "like an anthropologist on Mars." Grandin's case was described by neurologist Oliver Sacks in his 1995 book titled An Anthropologist on Mars: Seven Paradoxical Tales.

Perhaps due to their difficulties communicating with other humans, some autistics have gravitated toward working with animals. Temple Grandin's bestselling book Animals In Translation describes her observations and theories about animals, taken from her work with cattle. Dawn Prince-Hughes, diagnosed with Asperger's, describes her observations of gorillas in Songs of the Gorilla Nation. Another autistic author is Tito Mukhopadhyay, one of whose books is The Mind Tree.

Some infants who later show signs of autism coo and babble during the first few months of life, but stop soon afterwards. Others may be delayed, developing language as late as the teenage years. Still, inability to speak does not mean that people with autism are unintelligent or unaware. Once given appropriate accommodations, some will happily converse for hours, and can often be found in online chat rooms, discussion boards or websites and even using communication devices at autism-community social events such as Autreat.

Sometimes, the body language of people with autism can be difficult for other people to understand. Facial expressions, movements, and gestures may be easily understood by some other people with autism, but do not match those used by other people. Also, their tone of voice has a much more subtle inflection in reflecting their feelings, and the auditory system of a person without autism often cannot sense the fluctuations. What seems to non-autistic people like odd prosody; things like a high-pitched, sing-song, or flat, robot-like voice may be common in autistic children and some will have combinations of these prosody issues. Some autistic children with relatively good language skills speak like little adults, rather than communicating at their current age level, which is one of the things that can lead to problems.

Since non-autistic people are often unfamiliar with the autistic body language, and since autistic natural language may not tend towards speech, autistic people often struggle to let other people know what they need. As anybody might do in such a situation, they may scream in frustration or resort to grabbing what they want. While waiting for non-autistic people to learn to communicate with them, people with autism do whatever they can to get through to them. Communication difficulties may contribute to autistic people becoming socially anxious or depressed or prone to self-injurious behaviors. Recently, with the awareness that those with autism can have more than one condition, a significant percentage of people with autism are being diagnosed with co-morbid mood, anxiety and compulsive disorders which may also contribute to behavioral and functioning challenges.

Repetitive behaviors

Although people with autism usually appear physically normal and have good muscle control, unusual repetitive motions, known as self-stimulation or "stimming," may set them apart. These behaviors might be extreme and highly apparent or more subtle. Some children and older individuals spend a lot of time repeatedly flapping their arms or wiggling their toes, others suddenly freeze in position. Some spend hours arranging objects in a certain way rather than engaging in pretend play as a neurotypical child might, and becoming agitated if they are re-arranged or moved. Autistic children may demand consistency in their environment. A slight change in the timing, format or route of a routine or trip can be extremely disturbing to them. Autistics sometimes have persistent, intense preoccupations. For example, the child might be obsessed with learning all about computers, television programs, lighthouses or virtually any other topic. Some may repeat words from movies and watch certain bits over and over again. Repetitive behaviors can also extend into the spoken word; perseveration of a single word or phrase can also become a part of the child's daily routine.

Effects in education

Children with autism are affected by their symptoms every day, which set them apart from unaffected students. Because of problems with receptive language and theory of mind, they can have difficulty understanding some classroom directions and instruction, along with subtle vocal and facial cues of teachers. This inability to fully decipher the world around them often makes education stressful. Teachers need to be aware of a student's disorder, and ideally should have specific training in autism education, so that they are able to help the student get the best out of his or her classroom experiences.

Some students learn more effectively with visual aids as they are better able to understand material presented visually. Because of this, many teachers create “visual schedules” for their autistic students. This allows students to concretely see what is going on throughout the day, so they know what to prepare for and what activity they will be doing next. Some autistic children have trouble going from one activity to the next, so this visual schedule can help to reduce stress.

Research has shown that working in pairs may be beneficial to autistic children.[34] Autistic students have problems not only with language and communication, but with socialization as well. By facilitating peer interaction, teachers can help their students with autism make friends, which in turn can help them cope with problems or understand the world around them. This can help them to become more integrated into the mainstream environment of the classroom.

A teacher's aide can also be useful to the student. The aide is able to give more elaborate directions that the teacher may not have time to explain to the autistic child and can help the child to stay at an equivalent level to the rest of the class through the special one-on-one instruction. However, some argue that students with one-on-one aides may become overly dependent on the help, thus leading to difficulty with independence later on.

There are many different techniques that teachers can use to assist their students. A teacher needs to become familiar with the child’s disorder to know what will work best with that particular child. Every child is going to be different and teachers have to be able to adjust with every one of them.

Students with autism spectrum disorders sometimes have high levels of anxiety and stress, particularly in social environments like school. If a student exhibits aggressive or explosive behavior, it is important for educational teams to recognize the impact of stress and anxiety. Preparing students for new situations, such as through writing social stories, can lower anxiety. Teaching social and emotional concepts using systematic teaching approaches such as The Incredible 5-Point Scale or other cognitive behavioral strategies can increase a student's ability to control excessive behavioral reactions.

DSM definition

Autism is defined in section 299.00 of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) as:

  1. A total of six (or more) items from (1), (2) and (3), with at least two from (1), and one each from (2) and (3):
    1. qualitative impairment in social interaction, as manifested by at least two of the following:
      1. marked impairment in the use of multiple nonverbal behaviors such as eye-to-eye gaze, facial expression, body postures, and gestures to regulate social interaction
      3. failure to develop peer relationships appropriate to developmental level
      4. a lack of spontaneous seeking to share enjoyment, interests, or achievements with other people (e.g., by a lack of showing, bringing, or pointing out objects of interest)
      5. lack of social or emotional reciprocity
    2. qualitative impairments in communication as manifested by at least one of the following:
      1. delay in, or total lack of, the development of spoken language (not accompanied by an attempt to compensate through alternative modes of communication such as gesture or mime)
      3. in individuals with adequate speech, marked impairment in the ability to initiate or sustain a conversation with others
      4. stereotyped and repetitive use of language or idiosyncratic language
      5. lack of varied, spontaneous make-believe play or social imitative play appropriate to developmental level
    3. restricted repetitive and stereotyped patterns of behavior, interests, and activities, as manifested by at least one of the following:
      1. encompassing preoccupation with one or more stereotyped and restricted patterns of interest that is abnormal either in intensity or focus
      3. apparently inflexible adherence to specific, nonfunctional routines or rituals
      4. stereotyped and repetitive motor mannerisms (e.g., hand or finger flapping or twisting, or complex whole-body movements)
      5. persistent preoccupation with parts of objects
  2. Delays or abnormal functioning in at least one of the following areas, with onset prior to age 3 years:
    1. social interaction
    3. language as used in social communication
    4. symbolic or imaginative play.
  3. The disturbance is not better accounted for by Rett's Disorder or Childhood Disintegrative Disorder.

These are rules of thumb and may not necessarily apply to all diagnosed autistics.

Types of autism

Autism presents in a wide degree, from those who are nearly dysfunctional and apparently mentally disabled to those whose symptoms are mild or remedied enough to appear unexceptional ("normal") to others. Although not used or accepted by professionals or within the literature, autistic individuals are often divided into those with an