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10 Symptoms of Autism

autism symptoms

Symptoms of autism are varied among individuals diagnosed with Autism Spectrum Disorder (ASD). While autism affects both children and adults, the signs of autism are usually noticeable by the time a child is between 18 to 24 months of age. Although, this is not to say that it cannot be diagnosed any other time such as in the teenage years or even adulthood. There is such a wide variety of autism symptoms and each can range from mild to severe, which is why each person with autism is unique and can benefit from an individualized intervention plan for their health, behavior, and mental health. 

According to the Centers for Disease Control and Prevention (CDC), extensive research has shown that the brains of individuals with autism appear to develop differently than their peers without ASD. This difference in brain development is responsible for the challenges those with autism face.

Autism is a lifelong disability; however, this doesn’t mean that a full life cannot be lived. Symptoms can be managed if a treatment plan and intervention are in place by professionals such as an applied behavior analyst or clinician. In this article, you will learn about the 10 most common symptoms of autism and the details of each. 

The 10 symptoms of autism are:

  1. Developmental learning delays
  2. Over or under sensitivity to lights, sounds, touch, or tastes
  3. Difficulty communicating
  4. Repetitive movements and behaviors
  5. Difficulty in social situations
  6. Trouble with transitions
  7. Attachment to unusual interests
  8. Difficulty understanding emotions
  9. Recurring sleep problems
  10. Insufficient impulse control

Related resource: Top 25 Master’s in Autism Spectrum Disorder (ASD) Online

1. Developmental Learning Delays

Some individuals with autism can also have developmental learning delays, such as a specific learning disability or might be behind on meeting developmental milestones. For example, someone may have difficulty learning basic skill concepts such as personal hygiene or following simple one to two-step directions. There are specific “red flags” at each developmental stage that parents, teachers, and doctors should be aware of that may signify an issue. These changes or “red flags” may appear suddenly or over a period of time. 

The CDC lists some signs that something developmental could be going on: 

  • Can’t work simple toys (such as pegboards, simple puzzles, turning handles)
  • Doesn’t speak in sentences
  • Doesn’t understand simple instructions
  • Doesn’t play pretend or make-believe
  • Doesn’t want to play with other children or with toys
  • Doesn’t make eye contact
  • Loses skills he once had

2. Over or Under-Sensitivity to Lights, Sounds, Touch, or Tastes

10 Symptoms of AutismThose with autism tend to be overly sensitive to sensory stimuli such as loud noises, bright lights, or the feel of certain fabrics, for example. The brain’s ability to process incoming physical stimuli functions differently than someone without autism. As a result, those with autism often become easily overwhelmed. This informational onslaught can be frightening or confusing…or just plain frustrating. Some other examples are someone with autism may not be able to tolerate sharp food tastes and may prefer a bland diet. Or they may not be capable of tolerating touch well, due to an increase in skin sensitivity.

On the other end of the spectrum, someone with autism may be under-sensitive to their environment. They may be incapable of processing various stimuli and can appear immune to conditions that others would find intolerable. Examples of this may look like a child with autism banging their head, wanting a weighted vest, or stimming

3. Difficulty Communicating

By the time a child reaches 12-15 months old, they should be able to respond to simple commands such as nodding their head “yes” or “no” when asked a simple question. At this age, they should be making attempts to say words such as “mama” or “dada.” They may even begin to mimic small words they frequently hear such as “yay” or “uh-oh.” Children who display symptoms of autism may not speak at all or they may begin having longer periods of silence, in which they refuse to attempt to communicate with others, even people they love and trust. 

Communication is not all about the verbal; it involves reading facial expressions and eye contact, being cognizant of vocal tones, as well as understanding gestures. The overall ability to communicate heavily relies on a child’s social and intellectual development. 

4. Repetitive Movements and Behaviors

Repeating certain movements and behaviors, such as purposely shaking the head, a leg or arm, making intentional facial expressions, or pulling hair may be symptoms of autism. 

“Scientists categorize repetitive behaviors into two groups. So-called ‘lower-order’ repetitive behaviors are movements such as hand-flapping, fidgeting with objects or body rocking, and vocalizations such as grunting or repeating certain phrases. ‘Higher-order’ repetitive behaviors include autism traits such as routines and rituals, insistence on sameness and intense interests,” (Spectrum News). 

If you notice that your child often exhibits certain repetitive behaviors that are not appropriately connected to the task they are performing or the environment they are in, you may want to mention the behavior patterns to their physician.

5. Difficulty in Social Situations

One of the more easily recognized symptoms of autism is having a difficult time socializing with others. Children and adults with autism tend to shut down when placed in an overly-stimulating social environment. Sometimes they are mistakenly labeled as being “loners” or introverts. People that are “loners” prefer to spend time alone and enjoy their own company over the company of others. People living with autism tend to have difficulties relating to others when they are placed in a situation that requires social interaction. A way they can cope is to block out what is going on around them.

These social skills problems are rooted in some of the basic elements of ASD:

  • Delays and difficulty in acquiring verbal communication skills
  • Inability to read non-verbal communication cues
  • Repetitive or obsessive behaviors and insistence on adherence to fixed routine
  • Overwhelming sensory inputs

This is why social skills training is a major intervention used in the treatment of autism symptoms. 

6. Trouble With Transitions

People with autism spectrum disorder usually have a set routine they feel they must follow. Having an order of completing everyday tasks gives people with autism a calming comfort. A stable, self-regulated schedule helps appease an anxious mind. However, life is rarely predictable. Unexpected events can happen and ruin the normal routine. Small changes that throw off the schedule can cause distress. Big life transitions, such as starting school or graduating college, give some people with autism anxiety due to feeling a loss of control. If this person has not been taught self-regulation, they may have a panic attack or “meltdown.” 

In an ASD classroom, for example, it is important for the teacher to use timers, reminders, visuals, and social stories to communicate transitions and changes to the daily schedule. Storyboards and social stories can easily be made online or ordered through a particular ASD educational site. They can be tailored to fit each unique situation and need that the child may have. 

7. Attachment to Unusual Interests

One of the easiest autism symptoms to detect is an intense interest in unusual objects or topics, almost to the point of obsession. For instance, an autistic individual might love trains, stamps, record players, bottle tops, or spoons. People with autism know what they like and don’t care if it seems “uncool.” They can also be so passionate that they’ll devote vast amounts of time to their interests. Frequently, they become subject matter experts on topics they enjoy. Whether drawing, cooking, video games, or chemistry, individuals with autism spend endless amounts of energy practicing their hobby. Most children and adults with autism prefer doing these interests on their own, and there is nothing wrong with that! 

8. Difficulty Understanding Emotions

10 Symptoms of Autism-emotionsA misconception is floating around that people with autism lack emotion; this is completely false…they have feelings like everyone else. They simply struggle with understanding and interpreting emotions. Having autism spectrum disorder can make it hard to recognize emotions from facial and body language. People with ASD might not understand normal social cues like raised eyebrows or shrugs. They have difficulty detecting emotions or sarcasm as easily from a person’s vocal tone. Noticing anger, fear, disgust, and surprise is challenging. Due to this, it is common for people with ASD to misread situations and react inappropriately. Autism spectrum disorder causes difficulty in expressing one’s own emotions and experiencing empathy.

Parents, teachers, and therapists need to encourage emotional development in young children with autism; it is best to start intervening as early as possible. 

Two emotional awareness activity ideas from Raising Children are:

  • Label emotions in natural contexts: when you’re reading a book, watching a video or visiting friends with your child, you can point out emotions. For example, you might say, ‘Look – Sally’s smiling. She’s happy’.
  • Be responsive: respond to your child’s emotions by saying, for example, ‘You’re smiling, you must be happy’. You can also play up your own emotional responses – for example, ‘I am SO excited! Give me a high five’.

9. Recurring Sleep Problems

10 symptoms of autism-sleepAccording to Autism Speaks, nearly 80 percent of children with autism have a comorbid chronic sleep disorder, and individuals with autism are twice as likely to experience regular insomnia. They generally struggle with falling and staying asleep for the recommended eight hours each night. Unfortunately, lacking enough sleep can make other autism symptoms worse. Sleep-deprived people with ASD show more repetitive behaviors and more learning delays. 

It is reported in Spectrum News that “Sleep people with autism may also be less restorative than it is for people in the general population. They spend about 15 percent of their sleeping time in the rapid eye movement (REM) stage, which is critical for learning and retaining memories. Most neurotypical people, by contrast, spend about 23 percent of their nightly rest in REM.”

What makes sleeping so difficult? One reason is that autism spectrum disorder increases the sensitivity to sounds and lights. Children and adults with ASD can awaken instantly at even the slightest noise. They also may have anxious, hyperactive minds that are challenging to shut off for sleep, as many people with ASD also have ADHD or OCD. Clinicians often give people with autism melatonin drugs to sleep better.

Related: How to Help a Child with Autism Get a Good Night’s Sleep

10. Insufficient Impulse Control

Lastly, children and adults with ASD generally lack the skills to control their impulses. People with autism often act on their wants and desires without thinking things through first due to deficits in executive functioning. 

Executive function is the psychological term given to the set of cognitive skills that provide regulation of high-order thinking skills, including:

  • Planning and organization
  • Time management
  • Behavioral inhibition
  • Multitasking
  • Reasoning and problem solving

Autistic youth may go against their parents or caregiver’s instructions and act how they wish. For example, they may grab items they like at stores, they might disrupt a conversation to speak, they could leave an assigned work or school task to do what they like. Many children with ASD dislike sharing and take objects back immediately. Poor impulse control is definitely one of the autism symptoms that need to be addressed with an intervention.

Identifying these 10 symptoms of autism early and intervening is key to success in the future. Waiting to intervene could mean increasing the likelihood of significant cognitive, emotional/social, and behavioral deficits. These symptoms can be managed and children with autism can learn alternate behaviors, routines, and ways to express themselves with the help of parents, teachers, and ABA therapists.  

If you suspect your child may have symptoms of autism, contact your child’s physician. Help is available.

ABA Programs Guide Staff

Updated January 2021

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