University of Barcelona researchers say that the brain extracts important information for face recognition principally from the eyes, and secondly from the mouth and nose.
The research team obtained this result by analysing 868 male and 868 female face images in a way similar to that of the brain.
They observed that the most useful information is obtained from the images if their size is around 30 x 30 pixels.
The researchers also found that the images of eyes conveyed more reliable information to the brain compared to images of the mouth and nose, suggesting that face recognition mechanisms in the brain are specialized to the eyes.
According to the study group, their work complements a previously conducted study that showed that artificial face recognition systems have the best recognition performance when processing rather small face images - meaning that machines should do it just like humans.
The current study has been published in the open-access journal PLoS Computational Biology.