Developmental Issues and Milestones

Abstract

(from the chapter) Autism has been described as a lifelong disorder that emerges in the first year or two of life. Whereas Kanner's longitudinal assessment of his original cohort and the few follow-up studies that have been conducted through to adulthood suggest a generally stable diagnosis, recent literature challenges the notion that autism is definitively stable in all individuals diagnosed earlier in life. Prior studies indicate that most individuals diagnosed with autism continue to exhibit symptoms, whether profound or residual, through developmental stages; however, specific information about patterns of symptom change continues to be limited. In part, this is because research focused on examining symptomatology over the life course is inherently impeded by changes in diagnostic methodology, limitations of currently available assessment technology (particularly for older individuals), and other factors that may influence our ability to measure changes in the presentation of autism symptoms over time. This chapter explores the extant literature on symptom presentation across various developmental stages, ranging from onset during infancy, patterns of onset that include developmental regression, preschool through school-age years, and the adolescent/adulthood period. The chapter will focus on autistic disorder, but will consider the fuller spectrum that includes pervasive developmental disorder, not otherwise specified (PDD-NOS) and Asperger syndrome (AS), particularly in the discussion of diagnostic stability. The term autism spectrum disorders (ASD) will be used when collectively referencing this group of disorders. (PsycINFO Database Record (c) 2014 APA, all rights reserved)