• The Behavioral Effects of Frequent Nightmares on Objective Stress Tolerance

      Hochard, Kevin D.; Heym, Nadja; Townsend, Ellen; University of Chester; Nottingham Trent University; University of Nottingham (Americal Psychological Association, 2016-03)
      Frequent nightmares have been linked to daily distress using self-report measures. The present study investigated the impact of frequent nightmares on a stressful cognitive test requiring participants to perform additions of two previously displayed single digit numbers from a number series, where display latency between digits becomes increasingly short - the Paced Visual Serial Addition Task-Computerized (PVSAT-C). Participants experiencing frequent nightmares (n=43) and controls (n=42) were compared on PVSAT-C performance. A significant main effect of nightmare frequency was observed with participants in the frequent nightmare group enduring the task for a shorter duration than controls (a behavioral measure of stress tolerance). Results suggest that individuals experiencing frequent nightmares have a reduced tolerance for stressors, leading to increased daily vulnerability to stressful stimuli. This study confirms previous findings linking nightmares and daily distress and extends the literature by providing objective evidence for the link between nightmares and reduced stress tolerance through behavioral testing. These findings highlight nightmares as a salient target for clinical intervention.
    • Exploring thematic Nightmare content and associated self-harm risk

      Hochard, Kevin D.; Ashcroft, Sam; Carroll, Janine; Heym, Nadja; Townsend, Ellen; University of Chester; Nottingham Trent University; University of Nottingham (Wiley, 2017-09-28)
      Nightmares have been shown to be robust predictors of self-harm risk, beyond depressive symptoms and hopelessness at times. However, few studies have investigated associations between nightmare content and increased self-harm risk. The present study explored associations of thematic nightmare content with history of self-harm, and risk of self-harm phenomena the morning following a nightmare. A mixed-method diary study was employed. Prospective nightmare reports were obtained from 72 participants. A total of 47 nightmare reports met inclusion criteria and were analyzed for themes using inductive thematic analysis. Chi-square and bootstrap Pearson’s correlation tests were performed to assess the associations between nightmare themes and self-harm history and risk of self-harm phenomena following a nightmare. ‘Powerlessness to Change Behavior’ was associated a history of self-harm engagement, whereas ‘Financial Hardship’ indicated reduced risk. Themes were not significantly associated with increased risk of self-harm phenomena following a nightmare. Content may be of use in detecting lifetime history of self-harm engagement particularly in populations where disclosure is seen as taboo. However, nightmare symptom severity remains better indicators of risk. Evidence for the utility of nightmare content in assessing immediate self-harm risk is presently lacking. Replication with increased power is recommended.
    • Investigating the Interaction Between Sleep Symptoms of Arousal and Acquired Capability in Predicting Suicidality

      Hochard, Kevin D.; Heym, Nadja; Townsend, Ellen; University of Chester (Wiley, 2016-08-02)
      Heightened arousal significantly interacts with acquired capability to predict suicidality. We explore this interaction with insomnia and nightmares independently of waking state arousal symptoms, and test predictions of the Interpersonal Theory of Suicide (IPTS) and Escape Theory in relation to these sleep arousal symptoms. Findings from our e-survey (n = 540) supported the IPTS over models of Suicide as Escape. Sleep-specific measurements of arousal (insomnia and nightmares) showed no main effect, yet interacted with acquired capability to predict increased suicidality. The explained variance in suicidality by the interaction (1%?2%) using sleep-specific measures was comparable to variance explained by interactions previously reported in the literature using measurements composed of a mix of waking and sleep state arousal symptoms. Similarly, when entrapment (inability to escape) was included in models, main effects of sleep symptoms arousal were not detected yet interacted with entrapment to predict suicidality. We discuss findings in relation to treatment options suggesting that sleep-specific interventions be considered for the long-term management of at-risk individuals.
    • The unidirectional relationship of nightmares on self-harmful thoughts and behaviors

      Hochard, Kevin D.; Heym, Nadja; Townsend, Ellen; University of Chester ; Nottingham Trent University ; University of Nottingham (American Psychological Association, 2015-03-01)
      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.