can be noticed during infancy. It is usually noticed during early childhood, which is between the ages of 2-6 years. The severity of symptoms varies. Children with autism may show a combination of behaviors. Autism is a lifelong condition.
Each child is different. Symptoms fall into 4 broad categories:
Poor or limited social relationships
Underdeveloped communication skills
Repetitive behaviors and unusual interests and activities
Signs of altered and confused sensory input
Children develop and change rapidly at this early stage. Symptoms often take the form of failure to progress. A child may also regress from previous achievements. Something wrong may be noticed at birth. However, it is more common to notice something wrong when your child is a toddler. They may not achieve normal social and developmental milestones.
The range of unusual behaviors is wide. Children have many different combinations of behaviors.
Poor or Limited Social Relationships
Symptoms may include:
Avoiding eye contact
Avoiding social contact and preferring to be alone
Not imitating others
Not understanding other people's feelings and needs
Failing to seek and even avoid personal attention
Being physically aggressive
Often having tantrums, even with very little to provoke them
Underdeveloped Communication Skills
Symptoms may include:
Never speaking—Some children with autism may not be able to learn how to speak. Or, they may only speak a few words.
Using language in unusual ways. Some children use incorrect words and change the meaning of common words.
Only echoing what they have heard, and speaking on their own.
Trouble with nonverbal communication—Body language is used and interpreted wrongly. For example, a hug may be considered an assault.
Not reacting to smiles the way a normal child would.
Repetitive Behaviors, Unusual Interests, and Activities
Autistic children usually:
Do not play imaginatively
Lack interest in normal activities for their age
May spend hours doing a single activity over and over again. For example, rocking or flapping a hand
May gesture frequently, or stare at specific objects
Demand consistency and predictability in their surroundings—Tiny changes may cause angry reactions
May be hyperactive, passive, and single-minded
Altered and Confused Sensory Input
Signs may include:
An unusual sensitivity to sound, smell, taste, sights, and touch
Responding to stimulation in unusual ways
Sniffing or licking toys
Feeling pain from a light touch, but ignoring more severe pain
Experiencing sounds as colors, and touches as sounds
Some people with autism have other disorders as well. These may include:
—These occur when communication between nerve cells in the brain is disturbed. This can cause strange sensations, emotions, and behavior. Also common are convulsions, muscle spasms, and loss of consciousness.
—This is a neurological disorder. The symptoms are tics, rapid, involuntary movements, or sounds that occur repeatedly.
Fragile X syndrome
—This is an inherited disorder of the X chromosome. It is the most common cause of inherited intellectual disability.
(PKU)—PKU is a genetic disorder of the enzyme that breaks down phenylalanine. Phenylalanine is an amino acid found in certain foods. Without a proper diet, PKU can lead to intellectual disability.
Tuberous sclerosis—This is a genetic disorder of the nervous system. It causes tumors to grow on the nerves in any part of the body. Neurofibromatosis can also produce other abnormalities. For example, changes in the skin or deformed bones.
About autism. The Autism Society website. Available at: http://www.autism-society.org/what-is. Accessed March 14, 2017.
Autism spectrum disorder. National Institute of Mental Health website. Available at: https://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd/index.shtml. Updated October 2016. Accessed March 14, 2017.
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