In 2016 Massimo Polidoro tested an Italian mother and daughter that were claiming a 90% and above success rate of psychic transmission using Zener cards. Upon restricting them from seeing each other's faces and to the use of a silent writing method their success rate dropped to no better than chance. The women were cognizant of the fact that they required visual contact to achieve transmission of the symbols saying, "This kind of understanding is so natural to us, all this attention to us is also very surprising. There are no tricks, but surely we understand each other with looks. It always happens."