DIFFERENTIAL LANGUAGE DEVELOPMENT IN ASD2Autism spectrum disorder (ASD) is a group of developmental disabilities that can cause significant social, communicative, and behavioral impairments. The diagnosis encompasses a variety of neurodevelopmental disorders including Asperger’s, pervasive developmental disorder not otherwise specified (PDD-NOS), and childhood disintegrative disorder. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) outlines the major diagnostic criteria of ASD. In addition to social deficits and communication difficulties, ASD is also classified by stereotyped or repetitive behaviors and interests, sensory issues, and in some cases, by cognitive delays (DSM-5, 2013). The first criteria deals with “persistent deficits in social communication and social interaction across multiple contexts” (DSM-5, 2013). This can range from irregular social-emotional reciprocity, poorly integrated verbal and nonverbal communication, and difficulty understanding and maintaining relationships to complete failure to initiate or respond in social interaction, total lack of facial expressions and nonverbal communication, and absence of interest in peers. The second criterion typifies the restricted, repetitive patterns of at least two behaviors, interests, or activities as demonstrated by current and/or past behavior. This list includes stereotyped, repetitive patterns of speech, motor movements, or patterns of behavior, inflexible adherence to routine, abnormally restrictive and fixated interests, and hyper- or hyporeactivity to sensory input. The DSM-5 emphasizes that these symptoms must be present early in development, whether noticeable or not, and that they can cause clinically significant impairments in social, occupational, or other important areas of life. While ASD frequently occurs comorbidly with intellectual disability, an ASD diagnosis should not be better explained by intellectual disability (DSM-5, 2013). Delayed language development is one of the most apparent symptoms of ASD. As such, a deficit in language processing is one of the earliest predictive factors of ASD in children.