Working memory and autism

Autism, or what is now referred to as autism spectrum disorder (ASD), is a behaviorally-defined and diagnosed neurodevelopmental disorder (Amaral, Schumann, and Nordahl, 2008). Because there is no generally accepted biomarker for ASD, researchers and medical practitioners have to rely on behavioral characteristics when making a diagnosis. The defining characteristics of ASD were agreed upon by a panel of experts in the field and are published in the Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-5; American Psychiatric Association, 2013). In the prior edition of the DSM, autism was included within the multicategorical diagnosis of Pervasive Developmental Disorder (PDD). This diagnosis included the categories of Autistic Disorder, Asperger syndrome, PDD-not otherwise specified (PDD-NOS), childhood disintegrative disorder, and Rett’s disorder (DSM-4-TR; American Psychiatric Association, 2000). Subsequent research identified problems with this multicategorical approach with limited reliability in the assignments of the DSM-4 subtypes (e.g. Walker et al., 2004).