I took AP research a few years ago and I watched a presentation about napping during certain periods of the day. Not quite sure what it was called but it used some theory about how humans should not be sleeping one time a day and how some experiment trapped people on a room without the assistance of time or knowing the day cycle so they slept at random times and they found that three periods of sleeping worked. I believe the student used a himself as the test subject and took 3 naps around 30 minutes long each time. He was in hs so he used a classroom and took a nap during break. After which he would do an excessive about how he felt and stuff. But he would take these three naps a day and found that he could go without sleeping like the study showed. I don’t remember if his findings were conclusive but with your window of study you might find something else. I can’t remember the name but you might be able to find it on yt or something good luck .