Autism is a developmental disorder characterized by social interaction and communication problems and limited and repetitive behaviour. In the first three years of their child’s lives, parents generally notice indications. These symptoms often grow progressively, although some autistic kids achieve their stage of development at a standard rate before they become worse.
A mixture of genetic and environmental variables is correlated with autism. Risk variables during pregnancy include certain infections such as rubella and fatal development restrictions and autoimmune diseases including valprose acid, alcohol, cocaine, pesticides and air pollution. Disputes surround other environmental causes suggested; for instance, the disproportionate vaccine hypothesis. Autism impacts the information processing of the brain by changing the relationships, organisation and synapses of nerve cells.Autism issues Autism developmental disorder characterized social interaction communication problems limited repetitive behaviour years child lives parents generally notice indications These symptoms grow progressively autistic kids achieve stage development standard rate worse mixture genetic environmental variables correlated autism Risk variables pregnancy include infections rubella fatal development restrictions autoimmune diseases including valprose acid alcohol cocaine pesticides air pollution Disputes surround environmental suggested instance disproportionate vaccine hypothesis Autism impacts processing brain changing relationships organisation synapses nerve cells Autism developmental disorder characterized difficulties social interaction communication restricted repetitive behavior Parents notice signs years child life These signs develop gradually children autism reach developmental milestones normal pace worsening Autism combination genetic environmental factors Risk factors pregnancy include infections rubella toxins including valproic acid alcohol cocaine pesticides air pollution fetal growth restriction autoimmune diseases Controversies surround proposed environmental vaccine hypothesis disproven Autism processing brain altering connections organization nerve cells synapses How occurs understood DSM autism severe forms condition including Asperger syndrome pervasive developmental disorder PDD NOS combined diagnosis autism spectrum disorder ASD Early speech therapy behavioral interventions children autism gain care social communication skills Although cure cases children recovered Not children autism live independently reaching adulthood successful autistic culture developed individuals seeking cure believing autism accepted difference treated disorder Globally autism estimated affect people 2015 2000s number people estimated 000 people worldwide developed countries children diagnosed ASD 2017 2000 United States occurs times males females The number people diagnosed increased dramatically 1960s partly diagnostic practice The question actual rates increased unresolved CharacteristicsAutism highly variable neurodevelopmental disorder appears infancy childhood generally steady remission People autism severely impaired respects normal superior Overt symptoms gradually age months established age years tend continue adulthood muted form distinguished single symptom characteristic triad symptoms impairments social interaction impairments communication restricted interests repetitive behavior Other aspects atypical eating common essential diagnosis Individual symptoms autism occur general population associate highly sharp separating pathologically severe common traits Social developmentSocial deficits distinguish autism autism spectrum disorders ASD Classification developmental disorders People autism social impairments lack intuition people granted Noted autistic Temple Grandin inability understand social communication neurotypicals people normal neural development leaving feeling anthropologist Mars Unusual social development apparent early childhood Autistic infants attention social stimuli smile respond Autistic toddlers differ strikingly social norms eye contact turn ability simple movements express pointing Three year children autism exhibit social understanding approach spontaneously imitate respond emotions communicate nonverbally turns However form attachments primary caregivers Most children autism display moderately attachment security neurotypical children difference disappears children higher mental development severe ASD Older children adults ASD perform worse tests face emotion recognition partly ability define person emotions Children high functioning autism suffer intense frequent loneliness compared autistic peers common belief children autism prefer Making maintaining friendships proves difficult autism For quality friendships number friends predicts lonely feel Functional friendships invitations parties affect quality life deeply There anecdotal reports systematic studies aggression violence individuals ASD The limited data children intellectual disability autism aggression destruction property meltdowns CommunicationAbout individuals autism develop natural speech meet daily communication Differences communication year life include delayed onset babbling unusual gestures diminished responsiveness vocal patterns synchronized caregiver years children autism frequent diverse babbling consonants word combinations gestures integrated Children autism requests share experiences simply repeat echolalia reverse pronouns Joint attention functional speech deficits joint attention distinguish infants ASD For pointing hand pointed object consistently fail point objects order comment share experience Children autism difficulty imaginative play developing symbols language pair studies high functioning children autism aged performed equally adults individually matched controls basic language tasks involving vocabulary spelling Both autistic groups performed worse controls complex language tasks figurative language comprehension inference people sized initially basic language skills studies people speaking autistic individuals overestimate audience comprehends Repetitive behaviorA young boy autism arranged toys rowAutistic individuals display forms repetitive restricted behavior Repetitive Behavior Scale Revised RBS categorizes Stereotyped behaviors Repetitive movements hand flapping head rolling body rocking Compulsive behaviors Time consuming behaviors intended reduce anxiety individual feels compelled perform repeatedly rigid rules placing objects specific order checking hand washing Sameness Resistance change insisting furniture moved refusing interrupted Ritualistic behavior Unvarying pattern daily activities unchanging menu dressing ritual This closely sameness independent validation suggested combining factors Restricted interests Interests fixations abnormal theme intensity focus preoccupation single television program toy game Self injury Behaviors eye poking skin picking hand biting head banging single repetitive injurious behavior specific autism autism appears elevated pattern occurrence severity behaviors Other symptomsAutistic individuals symptoms independent diagnosis affect individual family estimated individuals ASD unusual abilities ranging splinter skills memorization trivia extraordinarily rare talents prodigious autistic savants Many individuals ASD superior skills perception attention relative general population Sensory abnormalities autism considered core features good evidence sensory symptoms differentiate autism developmental disorders Differences greater responsivity walking responsivity distress loud noises sensation seeking rhythmic movements estimated autistic people motor signs include poor muscle tone poor motor planning toe walking deficits motor coordination pervasive ASD greater autism proper Unusual eating behavior occurs quarters children ASD extent diagnostic indicator Selectivity common problem eating rituals food refusal occur Parents children ASD higher levels stress Siblings children ASD report greater admiration conflict sibling siblings unaffected children siblings children Down syndrome aspects sibling relationship However reported levels closeness intimacy siblings children Down syndrome siblings individuals ASD greater risk negative poorer sibling relationships adults There tentative evidence autism occurs frequently people gender dysphoria Gastrointestinal problems commonly medical disorders people autism These linked greater social impairment irritability behavior sleep problems language impairments mood CausesIt long presumed common genetic cognitive neural levels autism characteristic triad symptoms However increasing suspicion autism complex disorder core aspects distinct occur Deletion duplication inversion chromosome abnormalities implicated autism Autism strong genetic basis genetics autism complex unclear ASD explained rare mutations major effects rare multigene interactions common genetic variants Complexity arises interactions multiple genes environment epigenetic factors change DNA sequencing heritable influence gene expression Many genes autism sequencing genomes individuals parents Studies twins heritability autism high ASD siblings autism times autistic general population However mutations increase autism risk identified Typically autism traced Mendelian single gene mutation single chromosome abnormality genetic syndromes ASDs selectively ASD Numerous candidate genes located small effects attributable gene Most loci individually explain cases autism The large number autistic individuals unaffected family members result spontaneous structural variation deletions duplications inversions genetic material meiosis Hence substantial fraction autism cases traceable genetic highly heritable inherited mutation autism parental genome Autism underdiagnosed women girls assumption male condition Maternal nutrition inflammation preconception pregnancy influences fetal neurodevelopment Intrauterine growth restriction ASD term preterm infants Maternal inflammatory autoimmune diseases damage fetal tissues aggravating genetic problem damaging nervous Exposure air pollution pregnancy heavy metals particulates increase risk autism Environmental factors claimed evidence contribute exacerbate autism include foods infectious diseases solvents PCBs phthalates phenols plastic products pesticides brominated flame retardants alcohol smoking illicit drugs vaccines prenatal stress Some MMR vaccine completely disproven Parents aware autistic symptoms child time routine vaccination This led unsupported theories blaming vaccine overload vaccine preservative MMR vaccine causing autism The theory supported litigation funded study elaborate fraud Although theories lack convincing scientific evidence biologically implausible parental concern potential vaccine link autism led rates childhood immunizations outbreaks controlled childhood diseases countries preventable deaths children Autism symptoms result maturation systems brain How autism occurs understood Its mechanism divided areas pathophysiology brain structures processes autism neuropsychological linkages brain structures behaviors The behaviors multiple pathophysiologies There evidence gut brain axis abnormalities involved 2015 review proposed immune dysregulation gastrointestinal inflammation malfunction autonomic nervous gut flora alterations food metabolites brain neuroinflammation dysfunction 2016 review concludes enteric nervous abnormalities play role neurological disorders autism Neural connections immune pathway diseases originated intestine spread brain Several lines evidence point synaptic dysfunction autism Some rare mutations lead autism disrupting synaptic pathways involved cell adhesion Gene replacement studies mice autistic symptoms closely developmental steps depend activity synapses activity dependent All teratogens agents birth defects risk autism weeks conception exclude possibility autism initiated strong evidence autism arises early development DiagnosisDiagnosis based behavior mechanism Under DSM autism characterized persistent deficits social communication interaction multiple contexts restricted repetitive patterns behavior interests activities These deficits early childhood typically age lead clinically functional impairment Sample symptoms include lack social emotional reciprocity stereotyped repetitive language idiosyncratic language persistent preoccupation unusual objects The disturbance accounted Rett syndrome intellectual disability global developmental delay ICD essentially definition Several diagnostic instruments Two commonly autism Autism Diagnostic Interview Revised ADI semistructured parent interview Autism Diagnostic Observation Schedule ADOS observation interaction child The Childhood Autism Rating Scale CARS clinical environments assess severity autism based observation children The Diagnostic interview social communication disorders DISCO pediatrician commonly performs preliminary investigation developmental history physically examining child warranted diagnosis evaluations conducted ASD specialists observing assessing cognitive communication family factors standardized tools account medical conditions pediatric neuropsychologist asked assess behavior cognitive skills aid diagnosis recommend educational interventions differential diagnosis ASD stage intellectual disability hearing impairment specific language impairment Landau Kleffner syndrome The presence autism harder diagnose coexisting psychiatric disorders depression Clinical genetics evaluations ASD diagnosed symptoms genetic Although genetic technology clinical geneticists link estimated cases genetic consensus guidelines limited high resolution chromosome fragile testing genotype model diagnosis proposed routinely assess genome copy number variations genetic tests developed ethical legal social issues emerge Commercial availability tests precede adequate understanding test complexity autism genetics Metabolic neuroimaging tests helpful routine ASD diagnosed age months diagnosis increasingly stable years life year meets diagnostic criteria ASD year continue years National Autism Plan Children recommends weeks concern completed diagnosis assessment cases handled practice Although symptoms autism ASD early childhood missed years adults seek diagnoses friends family understand employers adjustments locations claim disability living allowances benefits Girls diagnosed boys Underdiagnosis overdiagnosis problems marginal cases increase number reported ASD cases diagnostic practices The increasing popularity drug treatment options expansion benefits providers incentives diagnose ASD overdiagnosis children uncertain symptoms Conversely cost screening diagnosis challenge obtaining payment inhibit delay diagnosis hard diagnose autism visually impaired partly diagnostic criteria depend vision partly autistic symptoms overlap common blindness syndromes blindisms Autism issues ZodiacPage