Why humans do not make good vampires: testing the ability of humans to detect true blood

Background: Research indicating the effects of real blood or of its iconic representation on human behaviour has thus far concentrated on phobia and aggressiveness. Little is known about other responses or, more fundamentally, about the biological basis of all such responses.Aim: In this study it is examined whether or not humans are able to detect real blood.Methods: Human subjects (n = 89) were asked to distinguish different kinds of blood from red control fluids under varying visual and choice conditions. Relevant differences between subjects were tested for through written questionnaires, including standardized scales for disgust sensitivity (DS-R) and blood phobia (MBPI) and performance on two clinical olfactory tests.Results: Analysis of variance shows that humans are excellent detectors of animal blood (in casu pig blood), whereas the ability of detecting human blood is much less developed. Surprisingly, differences in olfactory capacities and personal experience with blood have no effect on blood ...