Stress reactivity in individuals with Non-REM Parasomnias, insomnia and good sleep

• Main Author: Young, Sarah Elizabeth
• Published: University of Glasgow 2011
• Subjects: 155; RZ Other systems of medicine : BF Psychology
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541213

To date, there is little research into either stress reactivity or the specificity of psychological characteristics in particular forms of sleep disorder. NREM parasomnias are a relatively un-studied group of sleep disorders. The purpose of this study was to gain greater insight into how people with NREM parasomnias respond to ‘threat’ and to life situations. In particular, the aim was to investigate how their responses to a psychological stressor compared to individuals with insomnia and to good sleepers by measuring autonomic arousal, as well as subjective appraisals of stress. Baseline levels of autonomic arousal were intended to provide insight into daytime arousal levels at the trait level. Participants (N = 38) were recruited from the general population and attended the University of Glasgow Sleep Centre to take part. Autonomic arousal was measured via continuous electrocardiogram (ECG) recordings of heart rate (HR) and cardiac vagal tone (CVT) whilst participants took part in baseline, stressor (a difficult mathematical task) and recovery phases. In general, group differences were not found, however this may be partly due to the small sample size and corresponding lack of power to detect differences. The results indicated that the NREM group reacted to stress in a similar way to good sleepers. In general, it was the insomnia group but not the NREM group whose data differed from good sleepers. However, both the NREM parasomnia and Insomnia groups exhibited a relatively higher (though not statistically significant) resting baseline HR compared to the good sleeper group, suggesting a higher level of underlying sympathetic arousal. The findings of this type of study have potentially important implications for the development of treatment programmes for NREM parasomnias. However, further work needs to be done before any conclusions can be drawn. The study was intended as an exploratory study and the preliminary findings indicate that further exploration is warranted.