Human Nurons Are Different From All Other Mammals Tested

Scientists have found that human nurons differ from all other mammalian neurons tested, with a significantly lower density of ion channels. Thei chanels are proteins on the surface of all cells, but they're specialized in neurons. That's basically how neurons conduct electricity as how they function. So therefore, why would the human ones be different from all the other mammals? Mammals that they've tested? Does it have to do with our diet? Does it has to do with a brain function, or someor kind of amount?