I think i believe this. A friend of mine is a virgin to late nights and all nighters. We were studying one night trying to cram for a test and communicating every so often on WhatsApp. At around 12AM, he told me he thought he was hallucinating. I laughed as he was only up for like 14 hours. He fell asleep shortly thereafter.

I can relate. I've only had two "all nighters" in my life, and felt utterly miserable each time.

Towards the end of both, I would develop minor visual hallucinations (seeing little things in the corner of my eye, etc.). 14 hours is a bit silly, though. 24 hours is probably the minimum for most people.