Morton Ann Gernsbacher, a professor of psychology at the University of Wisconsin–Madison, compares the orientation of toilet paper to the orientation of cutlery in a dishwasher, the choice of which drawer in a chest of drawers to place one's socks, and the order of shampooing one's hair and lathering one's body in the shower. In each choice, there is a prototypical solution chosen by the majority, and it is tempting to offer simplistic explanations of how the minority must be different. She warns that neuroimaging experiments—which as of 2007 were beginning to probe behaviors from mental rotation and facial expressions to grocery shopping and tickling—must strive to avoid such cultural bias and stereotypes.[8]