Holding a human brain in my hands is one of those memories that will stay with me forever (Don’t panic, I was working as an autopsy assistant!).

It is an unremarkable grey mass of udon noodle-like twists and turns, soft enough to slip through your fingers. Not what you would expect for the most mysterious and incredible organ in our body. I could write hundreds of columns on the brain but as an eternal optimist I am going with some recent good news.

Scientists have discovered that you can grow new brain cells with nothing more than a good night sleep! There are many different kinds of brain cells, each with a particular set of jobs to do.

The cells we can grow with sleep are those responsible for making Myelin. Myelin is important stuff – it is like the casing on your sausage, the sticky back plastic on your books or the plastic coating on your phone charging cable.

It wraps around nerve cells, protecting them and enabling messages to pass through your body at lightning pace.

This is how we can walk, talk and snatch our hands away when we touch something hot. In fact all the movements that we undertake rely on healthy Myelin coating our nerve cells. It is Myelin that is destroyed when someone has Multiple Schlerosis (MS), causing their movements and speech to become difficult.

Take the phone charger analogy – if you snip holes along the plastic coating, pretty soon the wires underneath get damaged and the charge cannot move along the cable as effectively anymore. We all talk about how we feel better, sharper, after a solid sleep and Myelin may provide the scientific explanation.

The cells that make Myelin are called Oligodendrocytes. Oligo = “not many”, dendro = “having a branched shape like a tree” and any long sciencey word ending in cyte (pronounced “site”) is talking about cells. If you drop a glob of runny paint on to some paper you will create a splat that looks like an Oligodendrocyte. These cells are impressively good at protecting our nerves – each Oligodendrocyte can coat 50 nerve cells with Myelin.

Research shows that Oligodendrocytes double in number during the phase of sleep called REM (Rapid Eye Movement). We fall in and out of REM sleep a few times each night. In total, about 20 to 25 per cent of our sleep time is spent in REM phase. Scientists have also observed that being forced to stay awake caused the genes responsible for stress, cell death and ageing to be turned on. This double header in favour of sleep is even more important for children and teenagers. They spend as much as 80 per cent of their sleep time in REM phase because it is so important for growth.

These new discoveries mean that you can complain about having “frayed nerves” and mean it literally! But thankfully science can help you to smooth them over with a decent bit of shut-eye.