Autism is a general term for a group of complex
disorders of brain development.
These disorders are characterized, in varying
degrees, by difficulties in social interaction, verbal and
nonverbal communication and repetitive behaviors.
The most obvious signs of autism and symptoms of
autism tend to emerge between 2 and 3 years of age.
No big smiles or other warm, joyful expressions
by six months or thereafter.
No back-and-forth sharing of sounds, smiles, or
other facial expressions by nine months or thereafter.
No babbling by 12 months.
No back-and-forth gestures, such as pointing,
showing, reaching, or waving by 12 months.
No words by 16 months.
No two-word meaningful phrases (without
imitating or repeating) by 24 months.