Autism Spectrum Disorder (ASD) is a broad term that describes a group of neurodevelopmental symptoms predominantly characterized by communication delays and impaired social functioning. In most cases, the symptoms of ASD are noticeable prior to age 2 or 3.
Early symptoms of ASD may include limited or no eye contact, limited or no sharing of social smiles, and abnormal responses to vocal sounds or nonverbal communication. Delayed onset in speech is typical and may remain limited. In adults, ASD may appear as strong feelings of awkwardness in social situations, difficulty empathizing with others, resistance to change in everyday routines, restricted interests, repetitive behaviors, and heightened reactions to sensory input.