ASD is a heterogeneous disorder i.e. no two individuals on the spectrum will have the same set of signs and symptoms. The severity and range of symptoms are highly variable. However, the symptoms or difficulties can be classified into core domains such as difficulty in social interactions, communication deficits, behavioral issues and unusual interests and certain physical attributes. An individual may present with anyone, or a combination of or all of these difficulties/symptoms. Signs and symptoms usually become noticeable in the first three years of life. This section details the range of these signs and symptoms which are usually observed in individuals with autism.

Individuals with ASD face difficulties in communicating and expressing their feelings. They also have trouble in understanding the feelings of the people around them. As they grow up, this social deficit is further affected due to feelings of anxiety and depression. This in turn intensifies the problem with social skills, making it hard for them to adjust or adapt to their surroundings.

Examples of Social Issues related to ASD:

  • Poor or fleeting eye contact
  • Delayed or lack of response to name
  • Isolated play (the child prefers to be aloof)
  • Inability to interpret gestures or non-verbal cues
  • Difficulty in expressing feelings
  • Lack of social awareness (difficulty in understanding personal space and boundaries)
  • Sensory issues (avoids touch or seeks more physical touch for example hugging, kissing, etc.)

Individuals with ASD may present with varying levels of communication skills. This ranges from being fluently verbal to nonverbal and the intensity of these challenges can be seen in their language processing abilities. About 25 to 30% of kids with Autism start developing vocabulary skills by 12 to 18 months, but may lose all progress by their second birthday.

Examples of Communication Difficulties are:

  • Delayed development of speech and language skills
  • Repetition of words, dialogues, and sentences (echolalia)
  • Irrelevant speech i.e. giving unrelated answers to questions.
  • Lack of interest in pretend play (does not pretend to feed a doll)
  • Difficulty in interpreting or understanding jokes, riddles or questions

Individuals with autism often have unusual interests and behaviors like:

  • Unusual and inappropriate play with toys
  • Obsessed with objects like bottle caps, papers, wires, buttons, key rings, water pipes, straws, plastic, etc
  • Lining up objects or toys
  • Inability to adjust to or adapt to minor changes in the routine or environment
  • Repetitive behaviors like hand flapping, spinning objects.
  • Smelling or mouthing objects
  • Strong avoidance of certain food items, tastes, textures of clothing, etc.
  • Unusual fears or dislikes, e.g. cutting nails, flowers, etc.
  • Self-stimulatory behaviors like rocking, tapping hands/feet

While social and behavioral issues are more obvious it these children, some characteristic physical features may also be noticed. These may also add to their difficulties in interacting with their environment.

Some physical features of Autism are:

  • Abnormal muscle tone (muscles may be too tight or too loose)
  • Bony prominences may visible e.g. winging of the Scapula (prominent shoulder blades due to weak muscles)
  • Flat Feet
  • Poor or lack of hand-eye coordination
  • Limb apraxia (difficulty in performing planned movements of the arms or legs)
  • Balance issues while sitting, standing or walking
  • Abnormal posture or lordotic back (excessive inward curvature of the spine or back bone)
  • Clumsiness
  • Unusual sweating
  • Abnormal reactions to sensory stimuli
  • Hyperactivity.
  • Impulsive and uncontrolled behavior e.g. acting without thinking
  • Poor attention span (gets distracted very easily)
  • Self – injurious behavior like head banging, biting oneself, etc.
  • Aggressive behavior towards others like biting, scratching, hair pulling, throwing objects, etc.
  • Temper tantrums or erratic mood or inappropriate emotional reactions
  • Lack of fear (cannot sense danger)
  • Fear of irrelevant objects or situations e.g. fear of pressure cooker or a black plastic bag.
  • Hypersensitivity or hyposensitivity to touch, sound, taste, smell, look or feel.
  • Disrupted or disturbed sleep patterns.
  • Odd eating or food habits e.g. may not eat food items which are white in color, etc.