What Does Level 1 Autism Look Like? ASD Symptoms

Medically Reviewed on 12/16/2021
What Does Level 1 Autism Look Like
Level I autism is the mildest form of autism and only requires minimal support. Learn about signs and symptoms of level I, level II, and level III autism

Autism spectrum disorder (ASD) is a neurological developmental disorder that affects how a person communicates and interacts with others.

People with ASD are classified into three levels depending on the severity of the condition according to the criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5):

  • Ability to communicate
  • Ability to adapt to new circumstances
  • Ability to extend horizons beyond narrow interests and manage daily life

ASD levels indicate the degree of support the affected individual requires:

  • Level I: Requires support (mild) 
  • Level II: Requires substantial support (moderate)
  • Level III: Requires very substantial support (severe)

While these levels can help determine what types of services and supports may be best for the person, they cannot predict or account for nuances in each person’s personality and behavior. Treatment and support thus need to be highly personalized.

Autism level I

  • Social communication
    • Deficits in social communication cause noticeable impairments even with support in place.
    • Difficulty initiating social interactions and exhibits clear examples of atypical or unsuccessful responses to others' social overtures.
    • May appear less interested in social interactions.
  • Restricted interests and repetitive behaviors
    • Rituals and repetitive behaviors (RRBs) significantly impair functioning in one or more contexts.
    • Resists attempts by others to disrupt RRBs or divert attention away from fixations.
  • May require minimum support
    • May require support when faced with social difficulties.
    • Usually able to communicate and speak in full sentences but has difficulty engaging in back-and-forth conversations with others.
    • May try to make friends.
  • Level I autism characteristics
    • Trouble initiating conversation.
    • Losing interest quickly.
    • Transitioning to a new topic.
    • Inflexible behaviors.
    • Difficulty making friends.
    • Trouble organizing or planning.
    • Difficulty getting acclimated to a new environment.


Autism is a developmental disability. See Answer

Autism level II

  • Social communication
    • Deficits in social communication skills, both verbal and nonverbal.
    • Even with social support in place, social impairments are visible.
    • Reduced or abnormal response to social overtures from others, as well as limited initiation of social interactions.
  • Restricted interests and repetitive behaviors
    • RRBs, preoccupations, and fixations appear frequently enough to be noticeable to the untrained eye and interfere with functioning in a variety of situations.
    • When RRBs are interrupted, there is obvious distress or frustration and it is difficult to refocus.
  • May require substantial support
    • Find it difficult to hold a conversation even with help.
    • More likely to respond inappropriately and speak in short sentences or phrases. 
    • Have very narrow interests and engage in repetitive behaviors, making it difficult for them to function in certain situations.
  • Level II autism characteristics
    • Nonverbal communication, i.e. turning away from the person with whom they are conversing.
    • Inflexible behaviors that limit their ability to function.
    • Coping with changes in the environment, which can cause them a great deal of distress.

Autism level III

  • Social communication
    • Severe deficits in verbal and nonverbal social communication skills which lead to severe functional impairments.
    • Very little social interaction initiation and very little response to social overtures from others.
  • Restricted interests and repetitive behaviors
    • Preoccupations, rituals, and repetitive behaviors significantly impair functioning in all areas.
    • Distress when rituals or routines are disrupted. 
    • Extremely difficult to divert attention away from a fixation or to return to it quickly.
  • Substantial support is required
    • Significant verbal and nonverbal communication impairments.
    • Problems expressing themselves verbally and nonverbally which can make it difficult to function, interact socially, and cope with changes.
    • Repetitive behaviors.
  • Level III autism characteristics
    • Avoiding interactions with others.
    • Highly inflexible.
    • Reacts strongly to changes.
    • Becomes highly distressed in situations where they are required to change focus or tasks.

How is autism diagnosed?

Doctors may use a combination of diagnostic methods to evaluate symptoms.

During evaluations, hearing, speech, and language problems are ruled out. These assessments are critical because autism has a significant impact on overall communication skills. Checklists and surveys from parents, teachers, and other doctors who have observed the person in a variety of situations can paint a picture regarding the individual's behaviors, interpersonal relationships, body language, verbal communication, and play habits.

A doctor will only make a diagnosis of autism if the information gathered meets the standard criteria for the disorder. Additional medical tests may be performed to obtain more information, although these results are not used to diagnose the condition but to identify other conditions that could be causing or worsening symptoms. 

Several tools may be used to screen for autism spectrum disorder (ASD), including:

  • Modified checklist for autism in toddlers, revised with follow-up (M-CHAT-R/F): Brief yes or no checklist for early detection in children aged 16-30 months.
  • Autism diagnostic interview-revised (ADI-R): Semi-structured interview with the child's parents conducted by a trained specialist.
  • Autism diagnostic observation schedule-generic (ADOS-G) interview: Structured interview with directed activities used by a trained specialist.
  • Childhood autism rating scale (CARS): Evaluates a child's relationship to people, adaptation to change, listening response, and verbal communication using a 15-point scale.
  • ASD test app: Screening tool in the form of a portable mobile app that aids in the informal detection of autism for parents, teachers, and medical professionals.

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What are signs to look for with autism?

Parents and teachers should be aware of the following signs and symptoms of autism in children:

  • Problems with social interactions: The child may prefer to play alone rather than with other children.
  • Trouble communicating: Some people may perceive the child as odd, difficult, or rude because they act differently or do not communicate in the same way as other children.
  • Repeating patterns of behaviors: This could be a movement, such as flapping hands or rocking, or it could be focusing on a routine. They may also have an unusual attachment to certain objects.
  • Sensitivity to sensory input: The child may not want to be touched.

What are the treatment options for autism?

The goal of treatment for patients with autism is to reduce symptoms while improving learning and development.

  • Applied behavior analysis (ABA): Commonly observed in schools and clinics. It assists the child in learning about positive behaviors and reducing negative ones.
  • Developmental, individual differences, relationship-based approach (DIR): Intended to aid in the child’s emotional and intellectual development by helping them develop communication and emotional skills. This type of treatment involves the parent or caregiver getting down on the floor with the child to engage in the activities that they enjoy.
  • Treatment and education of autistic and related communication-handicapped children (TEACCH): Uses visual cues, such as picture cards, to help children learn everyday skills.
  • Picture exchange communication system (PECS): Uses symbols to help the child learn to ask questions and communicate.
  • Occupational therapy: Teaches the child life skills, such as feeding, dressing, bathing, and understanding how to interact with others. The skills they acquire are intended to help them live as independently as possible.
  • Sensory integration therapy: Can help children who are easily agitated by sensory triggers such as bright lights, certain sounds, or the sensation of being touched.
  • Medications: Some medications can help with related symptoms, such as depression, seizures, insomnia, and difficulty focusing:
    • Risperdal (Risperidone) may be prescribed to help with irritability.
    • Other drugs, such as selective serotonin reuptake inhibitors, anti-anxiety medications, or stimulants, may be prescribed in certain cases, but they are not FDA-approved for autism spectrum disorder.

Can diet help with autism symptoms?

While there are still many unanswered questions about the best way to treat autism, avoiding certain foods may help with symptoms.

  • Simple sugars: Foods high in simple sugars may temporarily increase energy levels, which can contribute to hyperactive behavior.
  • Artificial ingredients: Foods containing artificial sweeteners, artificial colors, flavors or preservatives should be avoided.
  • Toxins: Foods high in toxins should be avoided. Examples include fish high in mercury and meat products with polychlorinated biphenyls, dioxins, pesticides, brominated flame retardants, and perfluorinated chemicals. 
  • MSG: Monosodium glutamate can cause overexcitation in the brain, resulting in hyperactivity..
  • Dairy: Exorphin is produced when casein (a type of protein found in dairy products) reacts with the stomach acid. Exorphin can cause brain fog, spaciness, and inability to concentrate
  • Gluten: Gluten has been linked to inflammation and decreased cerebellum function. According to some studies, gluten consumption by people with autism can impair cerebellum function.
  • Corn: Corn is the most pesticide-intensive crop in the country according to the US Department of Agriculture. A 2013 study suggests a possible link between glyphosate (a herbicide) exposure and autism risk.

However, there is no conclusive scientific evidence to support the efficacy of nutritional interventions to improve autism spectrum disorder symptoms. Furthermore, there are concerns about side effects safety, particularly when it comes to potential nutritional and vitamin deficiencies.

Medically Reviewed on 12/16/2021
Image Source: iStock Images

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