I made it to 82 hours. It was forced upon us (military training, trench digging sleep deprivation exercise). I made it all the way to enforced rest period. Others didn't.

Up to 48 hours things were mostly normal in all areas, I was just tired. After that second night things started to get weird. Hand eye coordination worsened dramatically (not good when swinging pick axes and shovels in close quarters with others). Speaking and forming thoughts was definitely affected negatively.

One funny thing was we'd frequently have to 'stand to' and prepare for an attack by downing tools and standing in the trench with our rifles ready to fire on any attackers. Standing still for long periods staring at nothing was enough to bring on repeated and severe micro-sleeps. I distinctly remember standing there and hearing clattering noises and soft cries of pain from the field around me. I wondered what it was, until I watched my trench buddy slip into a micro-sleep, his body go limp and fall into the bottom of the trench. His rifle made the characteristic clattering sound against the corrogated iron and his cry came from smashing his knees into the side of the trench as he crumpled.

I was 20 at the time, the youngest from my company and dealt best with the deprivation of anyone. Youth plays it's part I think, though I am also predisposed to need less sleep even now, so some genetic factor is probably at play too.

From 48 hours onwards I began to realise the less I did the more difficult things would be. I volunteered for soime arduous patrols during the day and we were all forced to do some recce's during the night. That night I fell twice, once down a bank. I cut my hand pretty badly. In a year of training it was the only time I injured myself. My performance was definitely affected.

Crouched under a tree in the pouring rain about 70 hours in I remember feeling physically sick from the brain fog. Night time caused the world to close in around me in a very disorientating way.

At about 80 hours I remember seeing an old Sergeant from early in my training as I was coming back from a patrol. My directing staff had gone back to their harbour area ahead of us as the assessment phase of the patrol was over and it was our responsibility to get back to our trenches.

So, free from interference I went over to shake his hand and found it to be extremely sharp and prickly. I recoiled and couldn't understand what was happening. Trying again I gripped tighter, feeling the sharp needle like pains in my hand again. For some reason I pulled him closer and then I felt the shooting pains right in my face, especially my lips.

As I stumbled backwards I forgot to let go of his hand. It came away and I fell back with it.

As I hit the ground hard my 'vision' cleared and I could clearly see I had been shaking hands with a Holy tree. The sharp pains were caused by the needle like spines digging into my skin.

I chucked the branch from my hand and got back in line.

No one noticed my excursion, they were too busy picking two of my patrol buddies up from the track. They were laying face down asleep having simply shut down right as they were walking along, falling face first into the dirt and staying there, snoring.

Sleep deprivation is a powerful drug!