Autism: Symptoms, Types, Identification

Autism: Symptoms, Types, Identification
Photo source: Getty images

Autism is a pervasive developmental disorder affecting reciprocal social interaction, communication skills, imagination and play. It is accompanied by limited, stereotyped, repetitive interests and activities of the child.

Most common symptoms

Show more symptoms


Autism is a pervasive, biologically determined neurodevelopmental disorder. It is a chronic disorder with great phenotypic heterogeneity and neurobiological comorbidities.

The autism spectrum is a range of neurodevelopmental conditions generally characterized by difficulties in social interactions and communication, repetitive behaviors, intense interests, and unusual responses to sensory stimuli. It is commonly referred to as autism or, in the context of a professional diagnosis, as autism spectrum disorder (ASD), but the latter term remains controversial among neurodiversity advocates, neurodiversity researchers, and many autistic people due to the use of the word disorder and due to questions about its utility outside of diagnostic contexts.

Given concerns about the appropriateness of the term disorder, many sources prefer to use the word "autism" without any additional words, on the basis that this is the least controversial term among people with different perspectives or (in the United Kingdom) autism spectrum conditions (ASC) rather than ASD. Source: Autism spectrum - Wikipedia.

Autism is a disorder that children are born with and that lasts a lifetime.

In the course of development, some symptoms, signs and characteristics may change, as well as the degree of disability, for better or for worse.

The diagnosis of autism remains unchanged.

Every child with autism is unique in their own way.

„It is not difficult to love a child who is healthy and beautiful, but only great love can stoop to love a child who is handicapped.“ (Prof. Jedlička)

„These children come into the world with an inability to make emotional contact, just as other children come into the world with intellectual or physical deficits.“ (Kanner In Thorová, 1973, s. 36 ).


The cause of autism is still unclear.


Although children share the "same diagnosis", they do not necessarily have the same signs, symptoms and symptoms associated with autism.

The world of an autistic child can be perceived as monotonous, abandoned, empty.

Autistic children don't cuddle or respond, for example, to the mother's call, to their name, they don't show affection or smile.

They don't like certain sounds, the reaction is a screaming fit, but they do love certain other sounds and find them soothing.

Children often have a strange gaze, find it difficult to make eye contact, and if they do take note of their surroundings, it is only with brief, sideways glances.

Gestures, facial expressions, facial expressions are not diverse.

They have a lot of stereotyped behaviours that make no sense.

They have excellent abilities in abstract and logical thinking, but their range of interests is limited.

Autists tend to be alone (not physically, but rather mentally), adhere to routines, have excessive interest in a specific narrow topic or area.

Each autistic child shows differences rather than similarities, different symptoms in varying degrees, which means that the approach of professionals and people working with such children is individual and tailored to each child, depending on his or her needs and level of impairment.

International Classification of Diseases (ICD-10): Autism spectrum disorder (ASD)

F84.0 Infantile autism

  • abnormal delayed development that manifests itself before the age of 3,
  • abnormalities are present in all three areas of psychopathology: social interaction, communication, and restricted, stereotypically repetitive behavior,
  • a range of non-specific deviations such as various phobias, eating disorders, sleep disturbances, affective and aggressive manifestations directed against oneself,
  • 3 - 4 times more common in boys than in girls

Qualitative disruption of reciprocal social interaction involves problems in the area of:

  • understanding and using different forms of non-verbal behaviour,
  • inability to understand other people's emotions and respond appropriately to them,
  • inability to adequately express one's emotions,
  • inability to share attention, experiences and expertise,
  • the inability to behave appropriately in different social situations.

A child with autism has difficulty fitting into society and forming relationships with others. He avoids contact with other people or is indifferent to these contacts, especially those of other children and peers. 

Qualitative impairment in communication skills is manifested in both verbal and non-verbal domains:

  • speech development is usually delayed and disrupted,
  • speech may not develop at all, with no attempt to compensate for speech deficits with gestures or facial expressions,
  • if speech is developed, it is characterised by difficulties in establishing and maintaining a conversation.

Children who are able to communicate verbally may experience symptoms typical of autism:

  • echolalia (repeating a word someone else said) - immediate or delayed,
  • neologisms (non-existent words),
  • distorted linguistic pragmatism (missing the context).

In the area of non-verbal communication we can observe a deficit in gesticulation.

A lack of imaginative activity replaced with a narrow repertoire of stereotyped activities means that:

  • the child is unable to play imaginatively with objects or toys (or with other children or adults),
  • functionality is suppressed at the expense of detail,
  • the child tends to focus on unimportant or trivial things, e.g., the earrings, not the person wearing them, or, the wheel instead of the whole train (toy),
  • the child has a limited framework of imaginative activities, mostly copied and dealt with only,
  • the child misses the point of activities that involve engaging with words (e.g., social conversation, literature, especially fiction, or word toys).

Stereotypical movements are also characteristic (spinning in place, spinning objects, nodding the head and arms, hand wringing, moving the fingers).

All kinds of mannerisms indicative of compulsive behaviour or rituals.

The child is characterized by fascination, i.e. extraordinary fascination of autistic children with some specific sensory stimuli, e.g., observing dripping water, flashing neon lights, etc.

They feel an object with their lips, they sometimes smell them.

In contrast, there are unusual, even extremely expressed fear reactions to certain stimuli, e.g. to the sound of a vacuum cleaner or to the screaming of children.

F84.1 Atypical autism

It differs from infantile autism in the time of onset (a delayed onset of symptoms is present after the child is 3 years of age) and the failure to meet all three domains of impairment (one or two of the three domains of impairment required for a diagnosis of autism are absent, even though abnormalities in the other domains are present).

Atypical autism most commonly arises in profoundly retarded individuals and in individuals with severe specific developmental disorder of receptive language.

F84.2 Rett syndrome

Rett syndrome affects ONLY in girls.

  • develops only in girls, while its cause is still unknown,
  • early child development in the early stages tends to be within the norm, but the reversal occurs between 7 and 24 months of life,
  • partial or complete loss of acquired manual and verbal skills, decreasing head growth,
  • general reardation in all areas,
  • loss of functional hand movements,
  • stereotypical hand movements, like hand wringing,
  • difficulty chewing,
  • excessive salivation with sticking out of the tongue,
  • spinal curvature in childhood,
  • epileptic seizures.

Almost all children with this diagnosis are mentally retarded.

Compulsive repetitive hand washing and other types of stereotyped hand movements make any activity impossible for them.

F84.3 Other childhood disintegrative disorder

  • As a rule, the development of the child is normal up to 2 years, later there are problems in the field of development, which occur in a few months,
  • around the time of the onset of the disorder, there is a definite loss of previously acquired skills with severe emotional problems,
  • At the same time, speech and communication impairment grows, but over time, abilities in the non-verbal area can be restored,
  • impaired speech and social interaction remain impaired throughout life.

The diagnosis requires a clinically significant loss of skills in at least two of the following areas:

  • expressive or receptive language,
  • play,
  • social skills or adaptive behaviour,
  • bowel or bladder control,
  • motor skills.

The disorder is very rare, or very rarely diagnosed, and its incidence is 10 times less common compared to autism.

F84.4 Overactive disorder associated with mental retardation and stereotyped movements

It is a vaguely defined disorder:

A. Severe motor hyperactivity (at least two symptoms must be present):

  • continuous motor restlessness manifest in running, jumping and other movements of the whole body.
  • marked difficulty in remaining seated (the child will usually remain seated for a few seconds at most except when engaged in a stereotypical activity),
  • grossly excessive activity in situations where relative stillness is expected,
  • very rapid changes of activity, so that activities usually last for less than a minute (occasional longer periods spent in highly favoured activities do not rule out this diagnosis). Very long periods of time spent in stereotyped activities may be compatible with this problem.

B. Repetitive stereotyped patterns of behaviour and activity (at least one of the following symptoms present)

  • fixed and frequently repeated motor mannerisms (either complex movements of the whole body or partial movements such as hand flapping),
  • excessive and non-functional repetition of activities that are constant in form (for example, play with a single object, e.g. running water, or a ritual of activities, i.e. either alone or involving other people),
  • repetitive self-injury,
  • lacks varied, spontaneous, symbolic asocial imitative play appropriate to the developmental level.

C. IQ is below 50

D. There is no social impairment of the autistic type

F84.5 Asperger's syndrome

  • the same type of qualitative impairments in social interaction typical of autism, together with a limited, stereotyped, repetitive repertoire of interests and activities,
  • there is no overall delay or retardation of speech or cognitive development,
  • Most individuals have normal general intelligence, but are usually quite clumsy.

Asperger's syndrome occurs predominantly in boys (in a ratio of about 8:1).

Diagnostic criteria for Asperger syndrome according to ICD-10:

A. No clinically significant general delay in spoken or receptive language or cognitive development:

  • a definitive diagnosis must confirm that the child was using single words around the age of 2 years or earlier,
  • self-help ability, adaptive behaviour and interest in surroundings during the first three years should be at the level of normal rational development,
  • motor skills may be delayed - motor clumsiness.

B. Qualitative impairment in social interaction (as manifested by at least two of four of the following):

  • inability to appropriately use eye-to-eye gaze, facial expression, body posture and gesticulation for social interaction,
  • inability to develop relationships with peers that involve sharing interests, activities and emotions,
  • lack of social-emotional reciprocity, which manifests as a disturbed or deviant response to other people's emotions,
  • lack of adaptation of behaviour to social context, poor integration of social, emotional and communicative behaviour. Lack of spontaneous pursuit of fun or activities with other people.

C. Restricted repetitive and stereotyped patterns of behavior, interests, and activities,

D. Criteria are not met for another specific Pervasive Developmental Disorder

Learn more: 
What is Asperger's syndrome? How is it manifested and how to manage it? 
What is Asperger's Syndrome? Living with Asperger's: does your child have it?

F84.8 Other pervasive developmental disorders

Two groups of children fall into this category.

The first group are children who meet the following criteria:

  • the quality of communication, social interaction and play is impaired, but not to a degree consistent with a diagnosis of autism or atypical autism,
  • a wide range of symptoms; individual symptoms may be identical to the behaviour of a child with autism, but never occur in any given category in large numbers,
  • childcare is undemanding, but it can often be the other way around.

The diagnosis often occurs in children who have a severe form of activity and attention disorder, developmental dysphasia, unevenly developed cognitive abilities, mental retardation, and a low incidence of manifestations typical of autism.

The following are considered non-specific potential predictors of Pervasive Developmental Disorder:

  • anxiety,
  • inattentiveness
  • hyperactivity

The second group are children who meet the following criteria:

  • a severely disturbed area of imagination,
  • little ability to distinguish between fantasy and reality,
  • a distinct interest in a particular topic they are paying attention to

F84.9 Pervasive developmental disorder, unspecified

  • the age of recognition of the disorder varies,
  • social skills vary,
  • communication ability is weak,
  • there is usually no loss of manual skills.

The majority of those affected are in the intermediate to normal range of mental retardation. Diagnostic criteria are not precisely defined.

Can autism be confused with mental retardation?

Most children with autism are in the moderate and severe mental retardation range.

60% of children with autism have an IQ below 50, 20% of children with autism are in the mild mental retardation range, and 20% of children with autism have average or above average IQs.

Distinguishing between severe autism and mental retardation can be difficult because mental retardation can show symptoms that resemble autism.

However, unlike children with autism, mentally retarded children are more sociable, imaginative, like to communicate verbally and non-verbally, with gestures and facial expressions.

Sometimes early diagnosis is more difficult, especially when there are associated visual and hearing impairments.

Delayed development is characteristic of mentally handicapped children, but development in children with autism is qualitatively different.

Children with autism are comparable to healthy children on some developmental levels, such as motor skills, but in other areas, such as communication, social relationships, and imagination, they lag far behind.

Even if children with autism have some above-average skills, they cannot use them in practical life.

Determining the degree of mental retardation and the level of speech development has a very important role in terms of prognosis and the development of individual therapy for children with autism.

More favourable development can be expected in children with an IQ above 50 and the emergence of verbal expressions by the age of 5.


Diagnosis is made on the basis of a psychiatric examination of the child. It focuses on the manifestations and medical history obtained from the parents.

Identification is also complicated by the variety of clinical manifestations. 

What are the most common manifestations in children with ASD? (from the article Autism spectrum disorders in a nutshell: Do you know the symptoms?)

  • delayed onset of speech,
  • complete absence of speech abilities,
  • inability to strike up a conversation,
  • Inability to hold a conversation,
  • the inability to compensate for a verbal deficit with a non-verbal one,
  • abnormalities in non-verbal communication,
  • inability to maintain attention,
  • stereotypical patterns of behaviour and interests,
  • behavioral disorders, tantrums,
  • aggressive behaviour directed towards oneself and others,
  • other disorders or mood swings,
  • preoccupation with insignificant parts of objects,
  • motor abnormalities (hypotonia, tiptoeing, clumsiness),
  • Inability to establish and maintain relationships,
  • lack of emotional feeling,
  • lack of sharing joy and happiness with others,
  • absence of fear (in real danger),
  • weak to no imagination, imaginative power,
  • sensory deviations (sensitivity to noise, touch),
  • taste variations (preference for only certain foods),
  • sleep disorders.

Can autistic children be educated?

Education of pupils with pervasive developmental disorders with and without intellectual disabilities can be implemented in:

  • Primary school for students with autism.
  • In a special class for primary school students with autism.
  • A form of integration in mainstream primary school classrooms.

Regardless of whether pupils are educated in a primary school for pupils with autism, in a special class or in the form of integration, education and training is carried out according to:

  • Educational programmes for children and pupils with autism or other pervasive developmental disorders.
  • Educational programme for children and pupils with autism or other pervasive developmental disorders without intellectual disabilities.

One of the negative triggers of inappropriate behaviour in children with ASD is a communication problem.

Therefore, all efforts on the part of professionals, educators and parents should be directed towards the removal of these communication barriers in the form of alternative forms of communication such as alternative and augmentative systems.

The alternative and augmentative system is important for developing not only communication skills, but also cognitive skills to develop memory, practice eating, dressing or changing their activities.

The main method and the most widespread programme in working with children with autism and in their upbringing and education in the teaching process is the TEACCH Program.

Its general principle is:

  • individual approach,
  • visualisation,
  • structuring.  

The programme is tailored to the individuality, needs and personality of each child, reducing the anxiety and frustration stemming from a lack of speech understanding.

Inappropriate behaviour is eliminated and the ability to learn and gain a sense of safety and security in the environment is increased.         

Another method is the Picture Exchange Communication System, or PECS for short.

Almost every child is capable of learning it.

It is an image exchange communication system that falls under the form of Augmentative and alternative communication (AAC).

Its aim is to teach the individual functional communication:

  • How?
  • Why?
  • Who do I communicate with?

PECS is also a supportive form for the development of verbal communication.

The advantage is that:

  • it does not depend on the age of the child,
  • it does not require eye contact,
  • the child does not need to have thoroughly developed fine motor skills and verbal communication.

The principle of PECS is that if a child desires an item, he or she will receive it in exchange for a token.

The symbol can be a photograph, a picture, a model or real objects.

A communication book is created for each child according to his/her preferences, with the help of which he/she communicates.

Most of these children have significant problems with adaptability. Therefore, they need to have a sense of safety, security, logic and order in both the home and school environment to compensate for their handicap.

Final thoughts

When a child is born with a disability, the family finds itself in a situation that it did not expect, that it does not know, that it did not cause.

A lot depends on how the family and its surroundings cope with the situation.

The reaction and attitude of the family and the immediate surroundings is very important for the affected child, for his/her further development.

When working with such children, it is very important to consistently focus on the application of the aforementioned principles in relation to the uniqueness of the pupil.

Educational needs and conditions should be adapted to his/her personality, individuality and performance capacity.  

When used correctly, they improve access to information, the acquisition of new knowledge and skills, and integration into society or a group of peers.

When these methods are used ineffectively or deficiently, students may exhibit inadequate behaviors, incorrect learning principles, frustration, indifference, rejection, or disrespect for demands and authority.

This in turn prevents exclusion from peer groups and an overall reduced quality of life.

An adapted physical and social environment also contributes to successful learning. Activities and tasks for the child need to be visualised in advance in an individual daily schedule and procedures broken down into simple sections.

How it is treated: Autism

Will autism medication help? How is it treated?

Show more

Early Signs of Autism Video Tutorial | Kennedy Krieger Institute

fshare on Facebook

Interesting resources

  • Rosen NE, Lord C, Volkmar FR (December 2021). "The Diagnosis of Autism: From Kanner to DSM-III to DSM-5 and Beyond". Journal of Autism and Developmental Disorders51 (12): 4253–4270. 
  • Reed GM, First MB, Kogan CS, Hyman SE, Gureje O, Gaebel W, et al. (February 2019). "Innovations and changes in the ICD-11 classification of mental, behavioural and neurodevelopmental disorders". World Psychiatry18 (1): 3–19. 
  • Ripamonti L (April 2016). "Disability, Diversity, and Autism: Philosophical Perspectives on Health". The New Bioethics22 (1): 56–70. 
  • Pellicano E, den Houting J (April 2022). "Annual Research Review: Shifting from 'normal science' to neurodiversity in autism science". Journal of Child Psychology and Psychiatry, and Allied Disciplines63 (4): 381–396. 
  • Elsherif, Mahmoud Medhat; Middleton, Sara Lil; Phan, Jenny Mai; Azevedo, Flavio; Iley, Bethan Joan; Grose-Hodge, Magdalena; Tyler, Samantha Lily; Kapp, Steven K.; Gourdon-Kanhukamwe, Amélie; Grafton-Clarke, Desiree; Yeung, Siu Kit; Shaw, John J.; Hartmann, Helena; Dokovova, Marie (20 June 2022). "Bridging Neurodiversity and Open Scholarship: How Shared Values Can Guide Best Practices for Research Integrity, Social Justice, and Principled Education". 
  • Fletcher-Watson S (2019). Autism: a new introduction to psychological theory and current debates. Francesca Happé (New & Updated ed.). Abingdon, Oxon: Routledge. p. 30. ISBN 978-1-315-10169-9
  • Lai MC, Lombardo MV, Chakrabarti B, Baron-Cohen S (April 2013). "Subgrouping the autism 'spectrum': reflections on DSM-5". PLOS Biology11 (4): e1001544. 
  • Walker N (2021). Neuroqueer heresies: notes on the neurodiversity paradigm, autistic empowerment, and postnormal possibilities. Fort Worth, TX. ISBN 978-1-945955-26-6. OCLC 1287945422.
  • Robison JE (2020). "My Time with Autism Speaks". In Kapp SK (ed.). Autistic Community and the Neurodiversity MovementAutistic Community and the Neurodiversity Movement: Stories from the Frontline. Singapore: Springer. pp. 221–232. 
  • Opar, Alisa (24 April 2019). "In search of truce in the autism wars". Spectrum. Simons Foundation. 
  • Opar, Alisa (6 May 2019). "A medical condition or just a difference? The question roils autism community". The Washington Post. ISSN 0190-8286. Archived from the original on 7 May 2019. Retrieved 23 April 2022.
  • Davis, Rachael; Crompton, Catherine J. (2021). "What do New Findings About Social Interaction in Autistic Adults Mean for Neurodevelopmental Research?". Perspectives on Psychological Science16 (3): 649–653.