He et al Study (2020)

• Aim

  • This study aimed to assess the effects of restricting mobile phone use before bedtime on sleep, pre-sleep arousal, mood, and working memory.
• Method

  • Thirty-eight participants were randomised to either an intervention group where members were instructed to avoid using their mobile phone 30 minutes before bedtime, or a control group, where the participants were given no such instructions. Sleep habit, sleep quality, pre-sleep arousal and mood were measured using the sleep diary, the Pittsburgh sleep quality index, the Pre-sleep Arousal Scale and the Positive and Negative Affect Schedule respectively.
• Results

  • Restricting mobile phone use before bedtime for four weeks was effective in reducing sleep latency, increasing sleep duration, improving sleep quality, reducing pre-sleep arousal, and improving positive affect and working memory.
• Contributions of the study to psychology

  • Mobile phone use can affect working memory and cognitive functions – the results of this study show that reducing mobile phone use before bed can reduce pre-sleep arousal and can be used on patients suffering from insomnia who show a high pre-sleep arousal
• Criticisms

  1. Data collection was too subjective – because the data collected was from a sleep diary, a  sleep quality questionnaire and  a scale on pre-sleep arousal  = these are all highly subjective. Should have collected more objective data
  2. The sample size consisted of only 38 people. This is too small, so  the sample needs to be larger in order for it to be be representative of the wider population and to be able to generalise the findings to the wider population  (stock standard response year 12’s)
• Contributions of the study to psychology

  • Mobile phone use can affect working memory and cognitive functions – the results of this study show that reducing mobile phone use before bed can reduce pre-sleep arousal and can be used on patients suffering from insomnia who show a high pre-sleep arousal