Absence of face recognition biases related to hand-washing behaviour in a hazardous health scenario

One of the main routes for the cross-transmission of infectious microorganisms is by the hands of health care workers (cf. Pittet et al., 1999). Recent health campaigns have highlighted the importance of hand-washing behaviou, especially in high-risk environments. Hence, this study used a hypothetical medical scenario to investigate face recognition linked to hand-washing behaviours (e.g. subject imagined she was a patient with an exposed injury in a hospital ward and observed the hand-washing habits of its medical staff). It was hypothesized that subjects would recognize the faces of staff who did not wash their hands better than the ones who washed them. There were 12 faces to be memorized in three conditions (washed hands, dirty hands, and neutral - i.e. unknown hand-washing behaviour). Experiment 1 (faces memorized individually) revealed that subjects (N=29) remembered faces of staff who washed and did not wash their hands better than the neutral ones. Experiment 2 (group memorization) showed that subjects' (N=31) accuracy to the faces in the three hand-washing conditions was statistically similar. No biases in reaction times were observed in the two experiments. In short, subjects did not attend differently to the hand-washing behaviour of medical staff. Since hygiene has strong biological roots (cf. Curtis, 2005), the lack of attention to hand-washing behaviours in a hazardous hypothetical scenario may be linked (among other reasons) to the fact that infectious microorganisms are invisible to the naked eye.