This study investigated whether the use of a television, computer, gaming console, tablet, mobile phone, or audio player in bed before going to sleep was associated with insomnia, daytime sleepiness, morningness, or chronotype. 532 students aged 18-39 were recruited from lectures or via e-mail. Respondents reported the frequency and average duration of their in-bed media use, as well as insomnia symptoms, daytime sleepiness, morningness-eveningness preference and bedtime/rise time on days off. Mean time of media use per night was 46.6 minutes. The results showed that computer usage for playing/surfing/reading was positively associated with insomnia, and negatively associated with morningness. Mobile phone usage for playing/surfing/texting was positively associated with insomnia and chronotype, and negatively associated with morningness. None of the other media devices were related to either of these variables, and no type of media use was related to daytime sleepiness.

ObjectivesThe aim of the present study was to investigate whether the personality variables morningness, flexibility, languidity and hardiness could predict sleep-related shift work tolerance for the day, evening and night shifts, respectively.DesignProspective study design with questionnaires administered in winter 2008/2009 (wave 1) and 2 years later in spring 2011 (wave 3).SettingDifferent healthcare institutions in Norway.ParticipantsThe sample comprised in all 700 nurses working a three-shift rotating schedule.Primary and secondary outcome measuresThe personality variables were assessed at wave 1, as were the demographic, lifestyle and work-related variables. Sleep-related shift work tolerance, assessed at wave 3, was measured separately for the day, evening and night shifts with the Bergen Shift Work Sleep Questionnaire.ResultsMorningness was positively associated with sleep-related day shift tolerance (p<0.001). Flexibility was positively associated with sleep-related tolerance for the evening as well as night shift (p<0.001). Furthermore, languidity was negatively associated with sleep-related shift tolerance for the day, evening and night shifts (p<0.001, <0.01, <0.05, respectively). Hardiness was positively associated with sleep-related tolerance for the day, evening and night shifts (p<0.001, <0.01, <0.05, respectively). Age was negatively associated with sleep-related shift tolerance for the day, night (p<0.01) and evening shifts (p<0.001).ConclusionsThe findings indicate that hardiness and languidity predict sleep-related shift work tolerance across all shift types among shift working nurses. The effects of flexibility and morningness seem to depend on the shift schedule. By and large, our results are in accordance with previous studies; however, we have now demonstrated the prospective importance of personality in relation to sleep-related shift work tolerance across different shifts.

The use of nicotine in the form of “snus” is substantial and increasing in some geographic areas, in particular among young people. It has previously been suggested that addictions may operate through a mechanism of attentional bias, in which stimuli representative of the dependent substance increase in salience, thus increasing the addictive behavior. However, this hypothesis has not been tested for the case of snus. The current experiment used a modified Stroop task and a dot-probe task to investigate whether 40 snus users show an attentional bias towards snus-relevant stimuli, compared to 40 non-snus users. There were no significant differences between the two groups on reaction times or accuracy on either Stroop or dot-probe task, thus failing to show an attentional bias towards snus-relevant stimuli for snus users. This could imply that other mechanisms may contribute to maintenance of snus use than for other addictions. However, this is the first experimental study investigating attentional bias in snus users, and more research is warranted.