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From Nordan Symposia
Jump to navigationJump to searchCreated page with 'File:lighterstill.jpgright|frame '''Autism''' is a disorder of neural development that is characterized by impaired social interaction and [[c...'
[[File:lighterstill.jpg]][[File:Autism3.jpg|right|frame]]
'''Autism''' is a disorder of [[brain|neural]] development that is characterized by impaired social interaction and [[communication]], and by restricted and repetitive [[behavior]]. These signs all begin before a child is three years old.[1] Autism involves many parts of the [[brain]]; how this occurs is not well understood.[2] The two other autism [[spectrum]] disorders (ASD) are [[Asperger syndrome]], which lacks delays in [[cognitive]] development and [[language]], and PDD-NOS, diagnosed when full criteria for the other two disorders are not met.[3]
Autism has a strong [[DNA|genetic]] basis, although the genetics of autism are [[complex]] and it is unclear whether ASD is explained more by rare mutations, or by rare combinations of common genetic variants.[4] In rare cases, autism is strongly associated with agents that cause birth defects.[5] Controversies surround other proposed [[environmen]]tal causes, such as heavy metals, pesticides or childhood vaccines;[6] the vaccine hypotheses are [[biologically]] implausible and lack convincing [[scientific]] [[evidence]].[7] The prevalence of autism is about 1–2 per 1,000 people; the prevalence of ASD is about 6 per 1,000, with about four times as many [[male]]s as [[female]]s. The number of people known to have autism has increased dramatically since the 1980s, partly due to changes in diagnostic [[practice]]; the question of whether actual prevalence has increased is unresolved.[8]
Parents usually notice signs in the first two years of their child's life.[9] The signs usually develop gradually, but some autistic children first develop more normally and then regress.[10] Although early behavioral or cognitive intervention can help autistic children gain self-care, social, and [[communication]] skills, there is no known cure.[9] Not many children with autism live independently after reaching adulthood, though some become successful.[11] An autistic [[culture]] has developed, with some individuals seeking a cure and others believing autism should be tolerated as a difference and not treated as a disorder.[12]
==Characteristics==
Autism is a highly variable neurodevelopmental disorder[13] that first appears during infancy or childhood, and generally follows a steady course without remission.[14] Overt symptoms gradually begin after the age of six months, become established by age two or three years,[15] and tend to continue through adulthood, although often in more muted form.[16] It is distinguished not by a single symptom, but by a characteristic triad of symptoms: impairments in social interaction; impairments in [[communication]]; and restricted interests and repetitive [[behavior]]. Other aspects, such as atypical eating, are also common but are not [[essential]] for diagnosis.[17] Autism's individual symptoms occur in the general [[population]] and appear not to associate highly, without a sharp line separating pathologically severe from common traits.[18]
==Social development==
Social deficits distinguish autism and the related autism spectrum disorders from other developmental disorders.[16] People with autism have social impairments and often lack the [[intuition]] about others that many people take for granted. Noted autistic Temple Grandin described her inability to understand the social communication of neurotypicals, or people with normal neural development, as leaving her feeling "like an anthropologist on Mars".[19]
Unusual social development becomes apparent early in childhood. Autistic infants show less attention to social stimuli, smile and look at others less often, and respond less to their own name. Autistic toddlers differ more strikingly from social norms; for example, they have less eye contact and turn taking, and are more likely to communicate by manipulating another [[person]]'s hand.[20] Three- to five-year-old autistic children are less likely to exhibit social [[understanding]], approach others [[spontaneous]]ly, imitate and respond to [[emotions]], communicate nonverbally, and take turns with others. However, they do form attachments to their primary caregivers.[21] Most autistic children display moderately less attachment [[security]] than non-autistic children, although this [[difference]] disappears in children with higher mental development or less severe ASD.[22] Older children and adults with ASD perform worse on tests of face and emotion recognition.[23]
Contrary to common [[beliefs]], autistic children do not prefer being alone. Making and maintaining [[friendships]] often proves to be difficult for those with autism. For them, the [[quality]] of friendships, not the number of friends, predicts how lonely they feel. [[Function]]al friendships, such as those resulting in invitations to parties, may affect their quality of life more deeply.[24]
There are many anecdotal reports, but few [[systematic]] studies, of aggression and [[violence]] in [[individua]]ls with ASD. The limited [[data]] suggest that, in children with mental retardation, autism is associated with aggression, destruction of property, and tantrums. A 2007 study interviewed parents of 67 children with ASD and reported that about two-thirds of the children had periods of severe tantrums and about one-third had a [[history]] of aggression, with tantrums significantly more common than in non-autistic children with [[language]] impairments.[25] A 2008 Swedish study found that, of individuals aged 15 or older discharged from hospital with a diagnosis of ASD, those who committed violent crimes were significantly more likely to have other psychopathological conditions such as [[psychosis]].[26]
==Communication==
About a third to a half of individuals with autism do not develop enough natural [[speech]] to meet their daily [[communication]] needs.[27] Differences in communication may be present from the first year of life, and may include delayed onset of babbling, unusual gestures, diminished responsiveness, and [[vocal]] [[pattern]]s that are not [[synchronized]] with the caregiver. In the second and third years, autistic children have less frequent and less diverse babbling, consonants, words, and word combinations; their [[gestures]] are less often [[integrated]] with [[words]]. Autistic children are less likely to make requests or share [[experiences]], and are more likely to simply repeat others' words (echolalia)[28][29] or reverse pronouns.[30] Joint [[attention]] seems to be [[necessary]] for functional speech, and deficits in joint attention seem to distinguish infants with ASD:[3] for example, they may look at a pointing hand instead of the pointed-at object,[20][29] and they consistently fail to point at objects in order to comment on or share an experience.[3] Autistic children may have difficulty with [[imaginative]] [[play]] and with developing [[symbols]] into [[language]].[28][29]
In a pair of studies, high-[[function]]ing autistic children aged 8–15 performed equally well as, and adults better than, individually matched controls at basic language tasks involving vocabulary and spelling. Both autistic [[groups]] performed worse than controls at [[complex]] language tasks such as figurative language, comprehension and [[inference]]. As people are often sized up initially from their basic language skills, these studies suggest that people speaking to autistic individuals are more likely to overestimate what their [[audience]] comprehends.[31]
==Repetitive behavior==
Autistic individuals display many forms of repetitive or restricted behavior, which the Repetitive Behavior Scale-Revised (RBS-R)[32] categorizes as follows.
*[http://en.wikipedia.org/wiki/Stereotypy Stereotypy] is repetitive movement, such as hand flapping, making [[sounds]], head rolling, or [[body]] rocking.
*[http://en.wikipedia.org/wiki/Compulsive_behavior Compulsive behavior] is intended and appears to follow rules, such as arranging objects in stacks or lines.
*Sameness is resistance to change; for example, insisting that the furniture not be moved or refusing to be interrupted.
*[http://en.wikipedia.org/wiki/Ritual#Psychology Ritualistic behavior] involves an unvarying [[pattern]] of daily activities, such as an unchanging menu or a dressing [[ritual]]. This is closely associated with sameness and an independent validation has suggested combining the two factors.[32]
*Restricted behavior is limited in [[focus]], interest, or activity, such as preoccupation with a single television program, toy, or game.
*[http://en.wikipedia.org/wiki/Self-injury Self-injury] includes movements that injure or can injure the [[person]], such as eye poking, skin picking, hand biting, and head banging.[3] A 2007 study reported that self-injury at some point affected about 30% of children with ASD.[25]
No single repetitive behavior seems to be specific to autism, but only autism appears to have an elevated pattern of occurrence and severity of these behaviors.[33]
==Other symptoms==
Autistic [[individuals]] may have symptoms that are independent of the diagnosis, but that can affect the individual or the [[family]].[17] An estimated 0.5% to 10% of individuals with ASD show unusual abilities, ranging from splinter skills such as the [[memorization]] of trivia to the extraordinarily rare talents of prodigious [http://en.wikipedia.org/wiki/Savant_syndrome autistic savants].[34] Many individuals with ASD show superior skills in [[perception]] and [[attention]], [[relative]] to the general [[population]].[35] Sensory abnormalities are found in over 90% of those with autism, and are considered core features by some,[36] although there is no good [[evidence]] that sensory symptoms differentiate autism from other developmental disorders.[37] Differences are greater for under-responsivity (for example, walking into [[things]]) than for over-responsivity (for example, distress from loud [[noise]]s) or for sensation seeking (for example, [[rhythm]]ic movements).[38] An estimated 60%–80% of autistic people have motor signs that include poor muscle tone, poor motor planning, and toe walking;[36] ASD is not associated with severe motor disturbances.[39]
Unusual eating behavior occurs in about three-quarters of children with ASD, to the extent that it was formerly a diagnostic indicator. Selectivity is the most common problem, although eating rituals and food refusal also occur;[25] this does not appear to result in malnutrition. Although some children with autism also have gastrointestinal (GI) symptoms, there is a lack of published rigorous [[data]] to support the [[theory]] that autistic children have more or different GI symptoms than usual;[40] studies report conflicting results, and the [[relationship]] between GI problems and ASD is unclear.[9]
At some point in childhood, about two-thirds of individuals with ASD are affected by sleep problems; these most commonly include symptoms of [[insomnia]] such as difficulty in falling asleep, frequent nocturnal awakenings, and early morning awakenings. Sleep problems are associated with difficult behaviors and family [[stress]], and are often a [[focus]] of clinical attention over and above the primary ASD diagnosis.[41]
Parents of children with ASD have higher levels of stress.[42] Siblings of children with ASD report greater admiration of and less conflict with the affected sibling than siblings of unaffected children or those with Down syndrome; siblings of individuals with ASD have greater risk of negative well-being and poorer sibling relationships as adults.[43][http://en.wikipedia.org/wiki/Autism]
==External links==
* '''''Wikimedia Commons''''' has media related to: [http://commons.wikimedia.org/wiki/Category:Autism Autism]
*[http://www.dmoz.org/Health/Mental_Health/Disorders/Neurodevelopmental/Autism_Spectrum/ Autism] at the '''''Open Directory Project'''''
[[Category: Health]]
[[Category: Psychology]]
'''Autism''' is a disorder of [[brain|neural]] development that is characterized by impaired social interaction and [[communication]], and by restricted and repetitive [[behavior]]. These signs all begin before a child is three years old.[1] Autism involves many parts of the [[brain]]; how this occurs is not well understood.[2] The two other autism [[spectrum]] disorders (ASD) are [[Asperger syndrome]], which lacks delays in [[cognitive]] development and [[language]], and PDD-NOS, diagnosed when full criteria for the other two disorders are not met.[3]
Autism has a strong [[DNA|genetic]] basis, although the genetics of autism are [[complex]] and it is unclear whether ASD is explained more by rare mutations, or by rare combinations of common genetic variants.[4] In rare cases, autism is strongly associated with agents that cause birth defects.[5] Controversies surround other proposed [[environmen]]tal causes, such as heavy metals, pesticides or childhood vaccines;[6] the vaccine hypotheses are [[biologically]] implausible and lack convincing [[scientific]] [[evidence]].[7] The prevalence of autism is about 1–2 per 1,000 people; the prevalence of ASD is about 6 per 1,000, with about four times as many [[male]]s as [[female]]s. The number of people known to have autism has increased dramatically since the 1980s, partly due to changes in diagnostic [[practice]]; the question of whether actual prevalence has increased is unresolved.[8]
Parents usually notice signs in the first two years of their child's life.[9] The signs usually develop gradually, but some autistic children first develop more normally and then regress.[10] Although early behavioral or cognitive intervention can help autistic children gain self-care, social, and [[communication]] skills, there is no known cure.[9] Not many children with autism live independently after reaching adulthood, though some become successful.[11] An autistic [[culture]] has developed, with some individuals seeking a cure and others believing autism should be tolerated as a difference and not treated as a disorder.[12]
==Characteristics==
Autism is a highly variable neurodevelopmental disorder[13] that first appears during infancy or childhood, and generally follows a steady course without remission.[14] Overt symptoms gradually begin after the age of six months, become established by age two or three years,[15] and tend to continue through adulthood, although often in more muted form.[16] It is distinguished not by a single symptom, but by a characteristic triad of symptoms: impairments in social interaction; impairments in [[communication]]; and restricted interests and repetitive [[behavior]]. Other aspects, such as atypical eating, are also common but are not [[essential]] for diagnosis.[17] Autism's individual symptoms occur in the general [[population]] and appear not to associate highly, without a sharp line separating pathologically severe from common traits.[18]
==Social development==
Social deficits distinguish autism and the related autism spectrum disorders from other developmental disorders.[16] People with autism have social impairments and often lack the [[intuition]] about others that many people take for granted. Noted autistic Temple Grandin described her inability to understand the social communication of neurotypicals, or people with normal neural development, as leaving her feeling "like an anthropologist on Mars".[19]
Unusual social development becomes apparent early in childhood. Autistic infants show less attention to social stimuli, smile and look at others less often, and respond less to their own name. Autistic toddlers differ more strikingly from social norms; for example, they have less eye contact and turn taking, and are more likely to communicate by manipulating another [[person]]'s hand.[20] Three- to five-year-old autistic children are less likely to exhibit social [[understanding]], approach others [[spontaneous]]ly, imitate and respond to [[emotions]], communicate nonverbally, and take turns with others. However, they do form attachments to their primary caregivers.[21] Most autistic children display moderately less attachment [[security]] than non-autistic children, although this [[difference]] disappears in children with higher mental development or less severe ASD.[22] Older children and adults with ASD perform worse on tests of face and emotion recognition.[23]
Contrary to common [[beliefs]], autistic children do not prefer being alone. Making and maintaining [[friendships]] often proves to be difficult for those with autism. For them, the [[quality]] of friendships, not the number of friends, predicts how lonely they feel. [[Function]]al friendships, such as those resulting in invitations to parties, may affect their quality of life more deeply.[24]
There are many anecdotal reports, but few [[systematic]] studies, of aggression and [[violence]] in [[individua]]ls with ASD. The limited [[data]] suggest that, in children with mental retardation, autism is associated with aggression, destruction of property, and tantrums. A 2007 study interviewed parents of 67 children with ASD and reported that about two-thirds of the children had periods of severe tantrums and about one-third had a [[history]] of aggression, with tantrums significantly more common than in non-autistic children with [[language]] impairments.[25] A 2008 Swedish study found that, of individuals aged 15 or older discharged from hospital with a diagnosis of ASD, those who committed violent crimes were significantly more likely to have other psychopathological conditions such as [[psychosis]].[26]
==Communication==
About a third to a half of individuals with autism do not develop enough natural [[speech]] to meet their daily [[communication]] needs.[27] Differences in communication may be present from the first year of life, and may include delayed onset of babbling, unusual gestures, diminished responsiveness, and [[vocal]] [[pattern]]s that are not [[synchronized]] with the caregiver. In the second and third years, autistic children have less frequent and less diverse babbling, consonants, words, and word combinations; their [[gestures]] are less often [[integrated]] with [[words]]. Autistic children are less likely to make requests or share [[experiences]], and are more likely to simply repeat others' words (echolalia)[28][29] or reverse pronouns.[30] Joint [[attention]] seems to be [[necessary]] for functional speech, and deficits in joint attention seem to distinguish infants with ASD:[3] for example, they may look at a pointing hand instead of the pointed-at object,[20][29] and they consistently fail to point at objects in order to comment on or share an experience.[3] Autistic children may have difficulty with [[imaginative]] [[play]] and with developing [[symbols]] into [[language]].[28][29]
In a pair of studies, high-[[function]]ing autistic children aged 8–15 performed equally well as, and adults better than, individually matched controls at basic language tasks involving vocabulary and spelling. Both autistic [[groups]] performed worse than controls at [[complex]] language tasks such as figurative language, comprehension and [[inference]]. As people are often sized up initially from their basic language skills, these studies suggest that people speaking to autistic individuals are more likely to overestimate what their [[audience]] comprehends.[31]
==Repetitive behavior==
Autistic individuals display many forms of repetitive or restricted behavior, which the Repetitive Behavior Scale-Revised (RBS-R)[32] categorizes as follows.
*[http://en.wikipedia.org/wiki/Stereotypy Stereotypy] is repetitive movement, such as hand flapping, making [[sounds]], head rolling, or [[body]] rocking.
*[http://en.wikipedia.org/wiki/Compulsive_behavior Compulsive behavior] is intended and appears to follow rules, such as arranging objects in stacks or lines.
*Sameness is resistance to change; for example, insisting that the furniture not be moved or refusing to be interrupted.
*[http://en.wikipedia.org/wiki/Ritual#Psychology Ritualistic behavior] involves an unvarying [[pattern]] of daily activities, such as an unchanging menu or a dressing [[ritual]]. This is closely associated with sameness and an independent validation has suggested combining the two factors.[32]
*Restricted behavior is limited in [[focus]], interest, or activity, such as preoccupation with a single television program, toy, or game.
*[http://en.wikipedia.org/wiki/Self-injury Self-injury] includes movements that injure or can injure the [[person]], such as eye poking, skin picking, hand biting, and head banging.[3] A 2007 study reported that self-injury at some point affected about 30% of children with ASD.[25]
No single repetitive behavior seems to be specific to autism, but only autism appears to have an elevated pattern of occurrence and severity of these behaviors.[33]
==Other symptoms==
Autistic [[individuals]] may have symptoms that are independent of the diagnosis, but that can affect the individual or the [[family]].[17] An estimated 0.5% to 10% of individuals with ASD show unusual abilities, ranging from splinter skills such as the [[memorization]] of trivia to the extraordinarily rare talents of prodigious [http://en.wikipedia.org/wiki/Savant_syndrome autistic savants].[34] Many individuals with ASD show superior skills in [[perception]] and [[attention]], [[relative]] to the general [[population]].[35] Sensory abnormalities are found in over 90% of those with autism, and are considered core features by some,[36] although there is no good [[evidence]] that sensory symptoms differentiate autism from other developmental disorders.[37] Differences are greater for under-responsivity (for example, walking into [[things]]) than for over-responsivity (for example, distress from loud [[noise]]s) or for sensation seeking (for example, [[rhythm]]ic movements).[38] An estimated 60%–80% of autistic people have motor signs that include poor muscle tone, poor motor planning, and toe walking;[36] ASD is not associated with severe motor disturbances.[39]
Unusual eating behavior occurs in about three-quarters of children with ASD, to the extent that it was formerly a diagnostic indicator. Selectivity is the most common problem, although eating rituals and food refusal also occur;[25] this does not appear to result in malnutrition. Although some children with autism also have gastrointestinal (GI) symptoms, there is a lack of published rigorous [[data]] to support the [[theory]] that autistic children have more or different GI symptoms than usual;[40] studies report conflicting results, and the [[relationship]] between GI problems and ASD is unclear.[9]
At some point in childhood, about two-thirds of individuals with ASD are affected by sleep problems; these most commonly include symptoms of [[insomnia]] such as difficulty in falling asleep, frequent nocturnal awakenings, and early morning awakenings. Sleep problems are associated with difficult behaviors and family [[stress]], and are often a [[focus]] of clinical attention over and above the primary ASD diagnosis.[41]
Parents of children with ASD have higher levels of stress.[42] Siblings of children with ASD report greater admiration of and less conflict with the affected sibling than siblings of unaffected children or those with Down syndrome; siblings of individuals with ASD have greater risk of negative well-being and poorer sibling relationships as adults.[43][http://en.wikipedia.org/wiki/Autism]
==External links==
* '''''Wikimedia Commons''''' has media related to: [http://commons.wikimedia.org/wiki/Category:Autism Autism]
*[http://www.dmoz.org/Health/Mental_Health/Disorders/Neurodevelopmental/Autism_Spectrum/ Autism] at the '''''Open Directory Project'''''
[[Category: Health]]
[[Category: Psychology]]
