Why does lack of sleep make me emotional?
Lack of sleep can inhibit the regulating action of the brain, specifically the prefrontal cortex, on the brain's amygdala - responsible for alarm, fear, and anger and cause emotional instability. Not getting enough sleep also impacts REM, the emotional processing stage of sleep, and can make other people's faces appear less happy and more hostile.
Lack of sleep and your emotions
So, let's take a closer look at what can happen to your emotions when you don't get enough sleep.
Lack of sleep can cause crankiness and anger
Lack of sleep often causes crankiness. How many of you are exhausted after a fun weekend, a long week's work, or because you have small children, or many demands to deal with? Tired individuals, whether children or adults, are more irritable and quick to anger. They may also feel sadder or more anxious.
In very simple terms, the parts of our brain that are responsible for emotions are the prefrontal cortex and the amygdala. They operate as a team.(1) The amygdala is deep in the brain and lays down emotional memories. Sometimes this is called our 'lizard brain' as it is the most primitive part of our complicated central nervous system. It's the first to register emotions such as alarm, fear, or anger - 'That person made me so angry, I could cry, I want to punch their lights out'. The prefrontal cortex (the sophisticate behind our forehead) regulates the amygdala, like a referee, to what is appropriate: 'Chill - they may have jumped the queue, but come on - please reduce this emotion to mild irritation'.
Lack of sleep, less than eight or nine hours of sleep a night, causes a build-up of sleep debt and reduces the frontal cortex's ability to calm the amygdala's big emotional response to a late bus or an insensitive comment. Even mild exhaustion can make you feel more sensitive and likely to be reactive; our brain can become like a full-on Big Brother episode, full of dramas.
Lack of sleep affects your ability to process emotions
REM (Rapid Eye movement) is our dreaming sleep stage when emotional processing takes place. The brain can store a memory of a worrying event while inhibiting the chemical stressors that accompanied the event. That way we can remember what happened without reliving all the emotions we felt at the time.(2) If sleep time is reduced, there will be less time for the brain to do this type of mental processing that helps us cope with everyday stress. Alcohol can inhibit REM sleep, so that even though you may have had enough shut-eye in terms of hours, your nerves may feel frazzled.
Lack of sleep affects your ability to read others’ emotions
Studies have also shown that sleep deprivation can reduce the ability to read emotions on other people's faces. Tired people find it harder to recognise a happy expression and are more likely to identify a slightly angry face as more hostile.(3) This tendency is more pronounced in women. So, lack of sleep is not only making you feel more sensitive but also messes with your ability to see positivity or happiness around you. Over time, with not enough sleep, the world may appear to be a very bleak and depressing-looking place.
Other emotional responses to lack of sleep
Sleep-deprived women are more likely to complain of low mood, anxiety, and brain fog, while men may feel more aggressive. Children will act out, have tantrums, and will find it more difficult to control naughty behaviour.(4) Every tired person will find that they are less able to concentrate.
How does enough sleep help your emotions?
The good news is that getting more sleep can balance emotions, bring positive changes to mood, and can help reduce feelings of anxiety and anger. Researchers in the Netherlands, working with young people, increased the amount of sleep that one group had by getting them to bed a little earlier each night. Over two weeks, those that had increased the amount of time in bed and the amount of sleep that they were getting had better overall mood scores compared to those that made no changes to their sleep habits.(5)
Getting more sleep is a very simple strategy that can have a big positive impact on emotional well-being and mental health. If you are getting less than the recommended 8 – 9 hours' sleep a night, and you are feeling emotional, why not give it a twirl for a couple of weeks to see its effect.......?
Tips for getting more sleep:
- Take note of your sleep and wake time and figure out how much sleep you are getting presently, then decide on the best bedtime to ensure that you have all the sleep you need. Some people may need to build themselves up to this by going to bed 10 minutes earlier each night until the optimum bedtime is reached and a proper routine is established.
- Try a sleep tonic such as a cup of herbal tea (Chamomile, Lemon balm or Passiflora) before bed or Dormeasan Sleep drops in a little water.
- Sometimes a heavy meals or snacking can keep you keep awake, other times a small healthy snack before bed may help. See what approach works best for you, either way, avoid anything stimulating such as energy drinks, tea, or coffee in the late afternoon or evening.
- Make the last hour before bed relaxing: have a bath, dim the lights or read a book. Try to avoid screen devices such as TVs, phones and tablets, as the blue light in these can block the ability to produce melatonin, the hormone we need to feel sleepy.
For more help and information on getting to sleep check out the article Why does it take me so long to get to sleep? or, some of our other articles. We also have a six-day personalised sleep program that you can sign up for.