Distinguishing autism spectrum behaviors from behaviors relating to disorganized attachment can be challenging. There is, for instance, a notable overlap between both conditions in terms of behaviors deemed stereotypical. In addition, there are also similarities regarding some atypical social overtures. Responding to this overlap has been the subject for much debate in the literature. Disorganized attachment was first introduced and conceptualized by the attachment researcher, Mary Main. Main is considered the leading authority on coding this phenomenon. During the course of archival research, we obtained Main's notes on coding attachment in a group of 15 children with autism spectrum conditions (hereafter ASC). Drawing on these texts, this article explores Main's reasoning when making distinctions between ASC and attachment at the behavioral level. Our approach is informed by Chang's argument for the potential of "history as complementary science." Analysis indicates that, for Main, frequency and timing were important differential factors when attributing a behavior to either ASC or the child's attachment pattern.
Keywords: Ainsworth Strange Situation Procedure; attachment; autism; developmental psychology; differential diagnosis.