• Regression in language and speech skills (the cutoff for speech delay is 36 months)

• Regression in social skills

• Sequential, meaningless, restrictive, repetitive movements

Constitute the main (core) symptoms of autism.

Along with these, not making eye contact, focusing on spinning, moving, or light-emitting objects, not turning or looking when called by name, playing with a toy for hours, preferring the same toy, showing no interest in their surroundings, inability to focus, excessive hyperactivity or, conversely, extreme inactivity… are other important signs to suspect autism.