The Role of Sleep in our Mental Performance

We've all heard about how much sleep plays a crucial role in maintaining our mental health. It's often said so much, in fact, that I think many of us over-look and dismiss the value of sleep because of its seemingly simple relevance. The reality of it is, disruptions to sleep patterns, or irregular sleeping routines, can have significant effects on emotional well-being, cognitive function, and overall mental resilience. Let me explain...

Over the past 6 months I've been paying extra close attention to my mood and its disruptors. I've observed that, for me personally, sleep happens to be one of the biggest influences in my stability, (alongside nutrition, exercise, sunlight and social). Sleep is one of my favourite things to do, but despite loving it so much, I realised that I wasn't respecting it.

Chasing cheap dopamine hits on COD until the early hours, or sleeping in after my alarm, hating the previous version of myself every morning and feeling incapable of sticking to a routine, was not a feeling I wanted to get too familiar with. And that's kind of where things started. I decided I wanted to "get more out of Summer", so began to get up as early as I could to get as much sunlight as I could... after all, sunlight is super beneficial for our mental health. Getting up at a consistent time was proving almost impossible, until I realised that the night time routine was the prep work... and I still wasn't meeting a consistent bedtime. 

Since around April, I've been making a conscious effort to head out and catch what we can of the sunset. We take our little dog out, use the time to talk, and watch the sun go down. These walks didn't really develop a consistency until August, and I'm so grateful they did, because the sunsets have been incredible! The natural beauty aside, I think being outside during the gradual change from light to dark helps me to wind down for the evening, contributing towards a more consistent and restful sleep. I've genuinely felt more chilled within myself, less anxious, less depressed, have better memory, better emotional regulation, more clarity and feel a more positive vibe overall. All since maintaining a healthier sleep routine.

It's not just a coincidence that a regular(ish) bedtime and (mostly) consistent wake-up has me feeling more uplifted and resilient. Here's some of the science....

1. Emotional Regulation

- Healthy Sleep: A full night of sleep, particularly deep non-REM (Rapid Eye Movement) and REM sleep, helps the brain process emotions and memories. Adequate sleep ensures you can manage stress, handle difficult emotions, and approach social situations calmly.

- Sleep Deprivation: Lack of sleep makes emotional regulation difficult, increasing irritability, anxiety, and the likelihood of mood swings. Studies show that people who are sleep-deprived are more likely to react negatively to stressful events and may have less emotional control.

2. Cognitive Functioning

- Healthy Sleep: During sleep, the brain consolidates memories, processes information, and clears toxins that accumulate during the day. This process helps improve focus, decision-making, and problem-solving skills.

- Sleep Deprivation: Insufficient sleep can impair cognitive functions, reducing your ability to concentrate, make decisions, and think clearly. Over time, this can lead to increased frustration, forgetfulness, and even depression.

3. Mental Resilience and Stress Response

- Healthy Sleep: When well-rested, the body and mind are better equipped to handle everyday stress. Good sleep strengthens your resilience to setbacks, helping you stay positive and mentally balanced.

- Sleep Deprivation: Chronic sleep deprivation lowers resilience, making it harder to cope with stress and more prone to mental health issues like anxiety, depression, and irritability. Over time, this can lead to burnout and feelings of overwhelm.

4. Brain Chemistry and Hormonal Balance

- Healthy Sleep: Regular, good-quality sleep can help prevent the onset of mental health disorders. It stabilises brain chemistry and hormonal balance, both of which play a role in mood regulation and emotional well-being.

- Sleep Deprivation: People with sleep disorders, like insomnia, are at a much higher risk of developing mental health issues such as depression, anxiety disorders, and even more severe conditions like bipolar disorder. Sleep problems are both a symptom and a contributor to these disorders, creating a vicious cycle that can be difficult to break without additional support.

5. Impact on Other Conditions

- ADHD: Poor sleep can exacerbate symptoms of ADHD, including impulsivity, inattention, and hyperactivity. Lack of sleep impairs executive functions, making it harder for individuals with ADHD to stay focused, plan, and regulate emotions. 

- PTSD: For people with PTSD, nightmares and sleep disturbances can be common symptoms. Poor sleep worsens the intrusive memories and emotional distress associated with PTSD, making recovery more difficult.

- Anxiety and Depression: Anxiety can make it difficult to fall asleep or stay asleep, and lack of sleep can worsen anxiety symptoms. The relationship between depression and sleep is complex - depression may cause insomnia, and in turn, insomnia can intensify depressive symptoms.

6. Immune System and Overall Health

- Healthy Sleep: Sleep supports immune system function, which in turn protects physical health and indirectly supports mental well-being. When your body is physically healthy, your mental health is more stable.

- Sleep Deprivation: Long-term lack of sleep compromises the immune system, increasing the risk of physical illnesses. Physical health problems can add an extra layer of stress and anxiety, further straining mental health.

To wrap things up, getting enough quality sleep - typically 7-9 hours per night for adults - is essential for emotional regulation, mental resilience, cognitive function and overall mental performance. Improving sleep can significantly boost your mental health and reduce the risk of developing mental health disorders. Sleep is kind of the most precious rest we get, and I thought that deserved a blog post. 

Thank you for reading, 
Clare x

REFERENCES

Simon, E. B., Rossi, A., Harvey, A. G., & Walker, M. P. (2020). Overanxious and underslept. *Nature Human Behaviour*, 4(1), 100-110. - This paper explores the role of sleep in emotional regulation, showing that sleep deprivation heightens emotional reactivity and impairs cognitive functioning.

Kalmbach, D. A., Fang, Y., Arnedt, J. T., Cochran, A. L., & Deldin, P. J. (2018). Effects of sleep, physical activity, and shift work on daily mood: A daily diary study of healthcare workers. *Journal of Sleep Research*, 27(1), 1-9. - This study examines the influence of sleep quality on mental resilience and stress response, emphasizing that poor sleep weakens coping mechanisms in stressful environments.

Freeman, D., Sheaves, B., Goodwin, G. M., Yu, L. M., Nickless, A., Harrison, P. J., & Espie, C. A. (2017). The effects of improving sleep on mental health (OASIS): A randomized controlled trial with mediation analysis. *The Lancet Psychiatry*, 4(10), 749-758. - This clinical trial demonstrates that improving sleep can reduce the risk of developing mental health disorders, including anxiety and depression.

Becker, S. P., Sidol, C. A., Van Dyk, T. R., Epstein, J. N., & Beebe, D. W. (2017). Predicting ADHD symptoms in adolescents from childhood sleep problems. "Journal of Clinical Child & Adolescent Psychology", 46(2), 234-243. -This study highlights the strong connection between sleep problems in childhood and the worsening of ADHD symptoms in adolescence.

Miller, K. E., Jamieson, B., Granholm, A. C., & Ruth, D. (2018). Sleep disturbances in PTSD: Prevalence, theories, and treatment. *Current Opinion in Psychology*, 14, 84-89. - This paper reviews recent findings on sleep disturbances in PTSD, discussing how poor sleep worsens PTSD symptoms and complicates recovery.

Koo, B. B., Mataix-Cols, D., Fernández de la Cruz, L., Alonso, P., & Real, E. (2017). Sleep disturbances in obsessive-compulsive disorder: A systematic review and meta-analysis. *Sleep Medicine Reviews*, 31, 39-49. - This meta-analysis examines how sleep disturbances aggravate symptoms of anxiety disorders like OCD, with potential implications for depression.

Irwin, M. R. (2019). Sleep and inflammation: Partners in sickness and in health. *Nature Reviews Immunology*, 19(11), 702-715. - This review explores the bi-directional relationship between sleep and immune function, noting how sleep deprivation negatively impacts physical health, which in turn affects mental health.