Priming affects poor sleepers but not normal sleepers on an insomnia ambiguity task

With increasing importance being placed on the role of cognitive biases as a maintaining factor in insomnia, the influence of order effects on interpretative responses should be examined and subsequently accounted for. The aim of the present study was to examine whether asking participants about their sleep experiences, prior to testing for a perceptual bias, affects responses on a sleep-related ambiguity task. One hundred and seventeen undergraduate students, blind to the aims of the experiment, were issued either the Dysfunctional Beliefs and Attitudes to Sleep scale (DBAS-10) and Insomnia Severity Index (ISI) before, or following, completion of an Insomnia Ambiguity Task (IAT). As expected, a multivariate analysis of variance showed that the order in which participants completed the task affected the responses on the IAT with those given the DBAS-10 and ISI first, showing greater insomnia-related interpretations than those given the IAT first. However, on closer examination, this effect was evident only for those who were defined as poor sleepers, and that normal sleepers were largely unaffected by the order in which the tests are given. The results are discussed in terms of design and management of sleep-related research protocols involving implicit cognitive tasks.