2 The autism spectrum in the 21st century

As you learned in Week 1 [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] , knowledge about autism has come a long way in the last 8 decades – including recognition that it encompasses a great deal of diversity. The DSM-IV diagnostic criteria attempted to encompass this diversity by distinguishing differentiating sub-types such as childhood autism and Asperger syndrome (see Week 3, Section 2.2), but this proved problematic because the overlapping symptoms meant that diagnosis could not reliably differentiate between these categories.

The recent DSM-5 diagnostic criteria define autism as a single spectrum but also allow an individual profile to be specified for each person diagnosed. The ICD-11 criteria published in 2018 mirror DSM-5 in many respects, yet do recognise sub-types, differentiating autism with and without intellectual disability. Debate continues about the best way to capture both the shared features and the diversity of autism. Some different perspectives that bear on this issue are discussed in the next section.