Hochard, Kevin D.Heym, NadjaTownsend, Ellen2015-02-242015-02-242015-03-01Dreaming, 2015, 25(1), pp. 44-581053-079710.1037/a0038617http://hdl.handle.net/10034/345151This is the author's post-print version of an article published in Dreaming ©American Psychological Association - http://dx.doi.org/10.1037/a0038617 This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.Understanding the direction of the predictive relationship between nightmares and suicidal behaviors is important to model its underlying mechanisms. We examine the direction of this relationship and the mediating role of negative affect. A fixed interval diary study obtained pre-sleep and post-sleep measures of affect, nightmares, and self-harmful thoughts and behaviors (SHTBs) from 72 university students (88.9% female). The results show predictive utility of nightmares on SHTBs - indicating a four-fold increased risk of SHTBs. Additionally, results support the suggestion of a unidirectional predictive influence (of nightmares on likelihood of SHTBs but not vice versa). Moreover, post-sleep negative affect partially mediated the relationship between nightmares and post-sleep SHTBs. This empirically validates assumptions of directionality for future models.en-USnightmaresself-harmArticle1573-3351Dreaming