One surprising aspect of the Japanese is how superstitious they are, and there's a long list of "traditional folk beliefs" many Japanese subscribe to, some of which are quite colorful. Don't cut your fingernails at night, or you won't be able to be with your parents when they die. If you sneeze, it means someone is gossiping about you. Don't sleep with your head pointing north (kita-makura) or you will die, and so on. The world of ghosts is also quite popular, judging from the programs on Japanese TV which present shocking "proof" of the existence of these spirits all around us, or from the recent boom in ghost-related anime series. A person's sensitivity to these invisible apparitions is called reikan, and the Japanese believe that some people have the ability to sense these spirits while others don't. In the new anime Tasogare Otome x Amnesia (Dusk Maiden of Amnesia) there's a girl named Momoe who joins the school's Paranormal Investigation Club, but because she has no reikan (and is generally thick-headed), she can't see that the president of the club is the school's ghost, Yuko-san, despite the apparition sitting right in front of her. In my family my daughter is thought to have this ability to see ghosts -- she says she once saw a man dressed in a nice suit nod to her as she walked past a house one day, and we learned later that a man had died in the house the day before -- while I am blissfully ignorant of all paranormal activity around me.
Some people (like me) have zero sensitivity to ghosts.