I can do a lot of things while tired, but reading isn't one of them. I had to read some papers about plant disease today and even just a few minutes of staring at the paragraphs was enough to send me into a tired daze. I decided to scan each paper and summarize it, then sleep for a bit and try again.
I'm much more lucid now and it turns out my sleepy summaries weren't that great. One paper dealt with mechanisms by which plants can use bacterial DNA to combat viruses. The synopsis I had written down is "why politics is a thing". I'm sure it made sense at the time.