Medically reviewed by
Dacelin St Martin, MD
Triple board-certified in Sleep Medicine,
Internal Medicine, and Pediatrics.
Refreshing, restful sleep. Those words sound lovely and out of reach for many of us. Quality sleep is essential for good health and overall quality of life, yet this is a significant challenge for many people.
Insomnia in all its forms is too common in our society, with about 30 percent of the adult population experiencing this sleep disorder and trends showing increasing rates over time.
Although there can be multiple reasons behind insomnia, one of the most common causes of sleeplessness is related to psychological functions, which is why therapies like CBT-I (Cognitive Behavioral Therapy for Insomnia) work so well.
However, sometimes it’s possible to control anxious thoughts or rumination on specific subjects and allow for a better night’s sleep.
What’s a Sleep Diary All About?
There’s a reason why psychological therapists will often ask their patients to write things down.
Whether these topics are about the past, present, or future concerns, writing things down creates a powerful effect on human cognition.
Neuropsychologists have dubbed this the “generation effect.” That is, the information people create for themselves just ‘sticks’ better than something they’ve read by someone else.
This powerful effect has recently been studied in the context of falling asleep. The results of this study point to a strong correlation between making detailed to-do lists for the next day and falling asleep faster.
Writing down things people tend to ruminate on due to worry and anxiety can help offload the brain’s more negative, sleep-limiting thoughts onto a page.
Past or future?
The study in question asked 57 young adults to complete a writing assignment before an overnight sleep test (polysomnography).
The subjects were randomly asked to either i) write detailed to-do lists for tasks they need to complete in the next few days or ii) journal about tasks they have already completed. 
The study participants who created a nightly to-do list for upcoming tasks fell asleep significantly faster than the past achievements group. 
It stands to reason that what is ahead of us and not fully known causes more stress than things already done; however, the negative effects are significantly reduced when thoughts are offloaded onto a page.
If you have trouble falling asleep, give the to-do list a try. The whole process should be done every night before bed and shouldn’t take longer than 5 minutes.
Grab a notebook or piece of paper – and yes, use an actual pen and paper. The mere feeling of writing creates a deeper connection to the subject matter than typing something out on an electronic device.
Write down 3-5 tasks you have to do the next day or the day after. Be as specific as possible in your descriptions. Then go back and revisit your lists, adding one or two good things that happened to you that day. And that’s it.
The benefits may happen immediately, or it may take a night or two, but the key is to keep at it every night.
Writing things down is about controlling what keeps you from falling asleep. It helps declutter the brain from the thoughts and fears we tend to magnify.
Writing out a to-do list is a proven method of de-loading the busy brain and laying a foundation for bedtime calmness. This simple solution could be what you need for a better night’s rest.
- Bhaskar S, Hemavathy D, Prasad S. Prevalence of chronic insomnia in adult patients and its correlation with medical comorbidities. J Family Med Prim Care. 2016 Oct-Dec;5(4):780-784. doi: 10.4103/2249-4863.201153. PMID: 28348990; PMCID: PMC5353813.
- Scullin MK, Krueger ML, Ballard HK, Pruett N, Bliwise DL. The effects of bedtime writing on difficulty falling asleep: A polysomnographic study comparing to-do lists and completed activity lists. J Exp Psychol Gen. 2018 Jan;147(1):139-146. doi: 10.1037/xge0000374. Epub 2017 Oct 23. PMID: 29058942; PMCID: PMC5758411.
- Mueller, P. A., & Oppenheimer, D. M. (2014). The Pen Is Mightier Than the Keyboard: Advantages of Longhand Over Laptop Note Taking. Psychological Science, 25(6), 1159–1168. https://doi.org/10.1177/0956797614524581