I tried this during college, and nearly ended up hospitalized from hallucinations and a mini seizure. My sleep cycle was ruined for a year.<p>I had to pay around a thousand usd for a sleep study, and had to see a sleep specialist for a year.
He told me I was pretty lucky, if I tried it any longer I could have gotten permanent brain damage. He was suspicious of polyphasic claims, because he often saw people use modafinil in conjunction with this(especially among lawyers).<p>Maybe some people are genetically predisposed to this form of sleeping, but running experiments on yourself may not be worth it.