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Symptoms of Autism


The symptoms of Autism Spectrum Disorder (ASD) can range from mild to severe and vary significantly between individuals. However, common symptoms primarily affect social interaction, communication, and behavior. Some individuals may have average intelligence yet display little interest in social interactions, use limited verbal language, or engage in repetitive, self-stimulatory behaviors such as hand-flapping. Others may underreact to pain or overreact to sensory stimuli like loud sounds. While some individuals with ASD exhibit strong gross motor skills, they may struggle with fine motor tasks (National Institute of Mental Health, 2023).

Despite these challenges, people with ASD do not typically have physical traits that distinguish them from others. Instead, it is their communication style, behavior, and learning approaches that set them apart. The learning, thinking, and problem-solving abilities of individuals with ASD can range from exceptional to significantly impaired. Some individuals may require extensive daily support, while others may need less assistance (Centers for Disease Control and Prevention, 2023).

Today, the diagnosis of ASD encompasses several conditions that were once diagnosed separately. These include Autism, Asperger Syndrome, Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS), Rett Syndrome, and Childhood Disintegrative Disorder (American Psychiatric Association, 2013).

Symptoms of ASD usually appear before the age of three and persist throughout a person's life, though they may improve over time. Some children show early signs of ASD within the first few months of life, while others develop typically until around 18 to 24 months, after which they may stop gaining new skills or lose previously acquired abilities. Studies show that 33% to 50% of parents notice symptoms of ASD before their child’s first birthday, and 80% to 90% observe signs by the age of two (National Institutes of Health, 2021).


Symptoms of Autism


The symptoms of Autism Spectrum Disorder (ASD) can range from mild to severe and vary significantly between individuals. However, common symptoms primarily affect social interaction, communication, and behavior. Some individuals may have average intelligence yet display little interest in social interactions, use limited verbal language, or engage in repetitive, self-stimulatory behaviors such as hand-flapping. Others may underreact to pain or overreact to sensory stimuli like loud sounds. While some individuals with ASD exhibit strong gross motor skills, they may struggle with fine motor tasks (National Institute of Mental Health, 2023).

Despite these challenges, people with ASD do not typically have physical traits that distinguish them from others. Instead, it is their communication style, behavior, and learning approaches that set them apart. The learning, thinking, and problem-solving abilities of individuals with ASD can range from exceptional to significantly impaired. Some individuals may require extensive daily support, while others may need less assistance (Centers for Disease Control and Prevention, 2023).

Today, the diagnosis of ASD encompasses several conditions that were once diagnosed separately. These include Autism, Asperger Syndrome, Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS), Rett Syndrome, and Childhood Disintegrative Disorder (American Psychiatric Association, 2013).

Symptoms of ASD usually appear before the age of three and persist throughout a person's life, though they may improve over time. Some children show early signs of ASD within the first few months of life, while others develop typically until around 18 to 24 months, after which they may stop gaining new skills or lose previously acquired abilities. Studies show that 33% to 50% of parents notice symptoms of ASD before their child’s first birthday, and 80% to 90% observe signs by the age of two (National Institutes of Health, 2021).

Additional Symptoms and Early Warning SignsSocial SkillsCommunicationAtypical Interests and BehaviorsOther Symptoms

Additional Symptoms and Early Warning Signs

It is important to note that while some people without ASD may exhibit certain behaviors or symptoms, for individuals with ASD, these impairments significantly impact daily functioning and make life more challenging. Some key early warning signs that may indicate a person is Autistic:

  • Not engaging in "pretend" play by 18 months, such as pretending to feed a doll or play with toy food.
  • Avoiding eye contact and preferring to be alone.
  • Struggling to understand other people’s emotions or having difficulty expressing their own feelings.
  • Exhibiting delayed speech and language development.
  • Repeating words or phrases (echolalia).
  • Providing unrelated answers to questions.
  • Becoming upset by small changes in routine or environment.
  • Developing obsessive interests.
  • Engaging in repetitive movements, such as hand-flapping, body rocking, or spinning.
  • Having unusual reactions to sensory input, such as sound, smell, taste, or texture.



Social Skills

Social challenges are among the most common symptoms observed in all types of Autism Spectrum Disorder (ASD). These challenges may lead to significant obstacles in daily life. Some examples of social issues related to ASD include:

  • Not responding to their name by 12 months of age.
  • Avoiding eye contact.
  • Preferring to play alone.
  • Not sharing interests with others.
  • Only interacting to achieve a specific goal.
  • Exhibiting flat or inappropriate facial expressions.
  • Not understanding personal space boundaries.
  • Avoiding or resisting physical contact.
  • Not finding comfort in others during times of distress.
  • Having difficulty understanding others' feelings or expressing their own.

Typical infants show keen interest and curiosity about the world and the people around them. By their first birthday, they typically engage in social interactions, making eye contact, imitating words and actions, and using simple gestures like clapping and waving goodbye. In contrast, toddlers with ASD may struggle with social interactions and may find it challenging to participate in social games such as peek-a-boo or pat-a-cake. Some children with ASD may exhibit little interest in social relationships, while others may desire friendships but lack the skills to develop them. Many children with ASD find it particularly difficult to take turns and share, which can lead to social isolation as other children may be reluctant to play with them. Individuals with ASD often face challenges in expressing their feelings and understanding the emotions of others. Many are highly sensitive to physical touch, preferring not to be held or cuddled. Self-stimulatory behaviors, such as repeated hand-flapping, are also common among children with ASD. Furthermore, anxiety and depression can affect many individuals on the spectrum, complicating social interactions and relationships.




Communication

Individuals with Autism Spectrum Disorder (ASD) present a wide range of communication skills. While some children may speak fluently, others may be nonverbal or have very limited speech. Approximately 40% of children with ASD do not speak at all, and around 25% to 30% may use some words between 12 to 18 months but later lose those skills. Others may not begin to speak until later in childhood. Common communication challenges associated with ASD include:

  • Delayed speech and language development.
  • Echolalia, or the repetition of words or phrases.
  • Reversing pronouns, such as saying "you" instead of "I".
  • Providing unrelated answers to questions.
  • Not pointing or responding to pointing.
  • Using few or no gestures, such as not expressing a wave of goodbye.
  • Speaking in a flat, robot-like, or sing-song voice.
  • Not engaging in pretend play, such as pretending to feed a doll.
  • Struggling to understand jokes, sarcasm, or teasing.

For those with ASD who do communicate, language use may be atypical. Some children might struggle to form complete sentences and may use single words or repetitive phrases. Echolalia, where a child repeats what others say, can occur immediately or later; for example, responding to "Would you like some juice?" with the same phrase instead of an affirmative or negative response. While many typically developing children may briefly go through a stage of repetition, this typically fades by age three, whereas echolalia can persist in some children with ASD.

Individuals with ASD may find it challenging to use and understand gestures, body language, and tone of voice. For instance, they may not comprehend the significance of a wave goodbye, and their facial expressions and body language might not align with their spoken words. For example, they might smile while discussing something sad.

Communication patterns may also include confusion around pronouns, where individuals might interchange "I" and "you". Their speech might have a flat, monotone quality, and they may stand too close to conversation partners or focus excessively on one topic, often discussing their particular interests in depth rather than engaging in reciprocal dialogue. Some children with relatively good language skills may speak in an adult-like manner, missing the informal, playful communication style typical among their peers.




Atypical Interests and Behaviors

Individuals with Autism Spectrum Disorder (ASD) may display a range of atypical interests and behaviors. Some common examples include:

  • Lining up toys or other objects.
  • Playing with toys in the same way repeatedly.
  • Focusing on specific parts of an object or toy, such as wheels.
  • Demonstrating strong organizational skills.
  • Becoming upset by minor changes.
  • Having obsessive interests.
  • Following strict routines.
  • Engaging in repetitive movements, such as hand-flapping, body rocking, or spinning in circles.

Repetitive motions, often referred to as "stimming," can involve one part of the body or the entire body and may occur during play. For example, individuals with ASD might repeatedly flap their arms, rock from side to side, turn a light on and off, or spin the wheels of a toy car. These self-stimulatory behaviors serve various purposes, such as providing sensory input or helping to regulate emotions and maintain focus.

Many individuals with ASD thrive on routine and predictability. A disruption to their usual daily pattern, such as an unexpected stop on the way home from school, can lead to significant distress. In such situations, they may "lose control" and experience a meltdown or tantrum, especially if they are in an unfamiliar environment.

Some individuals with ASD may also develop seemingly unnecessary or atypical routines. For instance, they might feel compelled to check every window they pass by or insist on watching a video from start to finish, including previews and credits. Being prevented from engaging in these routines can lead to severe frustration and emotional outbursts (tantrums).




Other Symptoms

Individuals with Autism Spectrum Disorder (ASD) may exhibit a variety of additional symptoms, which can include:

  • Hyperactivity (excessive activity).
  • Impulsivity (acting without thinking).
  • Short attention span.
  • Aggression.
  • Self-injurious behavior.
  • Temper tantrums.
  • Atypical eating and sleeping habits.
  • Unusual mood or emotional reactions.
  • Lack of appropriate fear or excessive fear.
  • Atypical responses to sensory stimuli, including sound, smell, taste, sight, and touch.

People with ASD may have atypical reactions to sensory input. For example, they might overreact or underreact to pain or loud noises. Some individuals may have restrictive diets, consuming only a limited variety of foods, while others may engage in pica, eating nonfood items such as dirt or rocks. They may also experience gastrointestinal issues like chronic constipation or diarrhea.

Sleeping patterns can also be irregular, and emotional responses may be inconsistent. For instance, an individual might laugh or cry in situations where such reactions would not be expected or show little emotional response during moments that typically elicit a reaction. Additionally, some individuals with ASD may lack fear of genuinely dangerous situations, while displaying fear towards harmless objects or events.