1. So creative!

You go to sleep worrying over a problem, and when you wake up, the answer seems obvious.

According to Professor Penny Lewis from Cardiff University, the two main phases of sleep – REM and non-REM – work together to help us find out-of-the-box solutions to problems.

During non-REM sleep, millions of neurons fire simultaneously and strongly while your brain replays memories. As your brain reruns the memories, it makes links and connections to make sense of patterns.

During REM sleep, it all gets more chaotic, says Lewis. Different parts of your brain become activated, seemingly at random. Lewis suggests this allows your brain to search for similarities between seemingly unrelated concepts, so you can see a problem in a different way.

2. Better reaction times

Like a superhero in a movie, you will find your reflexes and reactions are sharper. Even if your job does not involve split-second decisions, your reaction times can still be a matter of life and death. Every time you get behind the wheel of a car, your reflexes matter.

According to the Sleep Foundation, if you skip a night’s sleep, your impairment is equivalent to a blood alcohol content of 0.1% - that is double the legal limit.

3. Laser sharp memory

When you get enough sleep, you will find you retain information more easily. You read it once, and you remember it. You no longer have that mental blank trying to remember that password – or forgetting why you walked into the kitchen.

Harvard Health says both animal and human studies suggest that the quantity and quality of sleep have a profound impact on learning and memory. Sleep helps you focus and learn, and it helps you consolidate memories.

4. Brighter mood

Sleep affects your mood, and your mood can affect how well you sleep.

Disturbed sleep is one of the first symptoms of depression. Conversely, chronically poor sleep can lead to depression. A study published in Sleep Journal in 2007 found that out of 10,000 adults, people with insomnia were five times more likely to develop depression.

Another study by the University of Pennsylvania found that subjects who were limited to only 4.5 hours of sleep a night for one week reported feeling more stressed, angry, sad, and mentally exhausted. When the subjects resumed normal sleep, they reported a dramatic improvement in mood.

* 17 March is World Sleep Day.

Improve your sleep, improve your mood

If you struggle with sleep and stress, the last thing you want to hear is that insomnia can exacerbate depression and anxiety. But it can help to know what you are dealing with, and to know there are many proven tactics and strategies you can use to improve your sleep.

If you are worried about your sleep, Harvard Medical School advises you first look at your sleep habits. Their recommendations include:

• maintaining a regular sleep-wake schedule
• avoiding caffeine, alcohol, nicotine, and other chemicals that interfere with sleep
• making your bedroom a comfortable sleep environment
• establishing a calming pre-sleep routine
• going to sleep when you are truly tired
• not watching the clock at night
• not napping too close to your regular bedtime
• eating and drinking enough – but not too much or too soon before bedtime
• exercising regularly – but not too soon before bedtime