Toggle Main Menu Toggle Search

Open Access padlockePrints

How do monkeys view faces? - A study of eye movements

Lookup NU author(s): Dr Kun Guo, Dr Robert Robertson, Dr Sasan Mahmoodi, Dr Yoav Tadmor, Professor Malcolm Young


Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Face perception plays a crucial role in primate social communication. We have investigated the pattern of eye movements produced by rhesus monkeys (Macaca mulatta) as they viewed images of faces. Eye positions were recorded accurately using implanted eye coils, while neutral upright, inverted and scrambled images of monkey and human faces were presented on a computer screen. The monkeys exhibited a similar eye scan pattern while viewing familiar and unfamiliar monkey face images, or while viewing monkey and human face images. No differences were observed in the distribution of viewing times, number of fixations, time into the trial of first saccade to local facial features, and the temporal and spatial characteristics of viewing patterns across the facial images. However, there was a greater probability of re-fixation of the eye region of unfamiliar faces during the first few seconds of the trial suggesting that the eyes are important for the initial encoding of identity. Indeed, the highest fixation density was found in the eye region of all the face images. The viewing duration and the number of fixations per image decreased when inverted or scrambled faces were presented. The eye region in these modified images remained the primary area of fixation. However, the number of fixations directed to the eyes decreased monotonically from the upright images through the inverted versions to the scrambled face images. Nonetheless, the eyes remain the most salient facial substructure regardless of the arrangement of other features, although the extent of salience which they attain may depend both on the low level properties of the eyes and on the global arrangement of facial features.

Publication metadata

Author(s): Guo K, Robertson RG, Mahmoodi S, Tadmor Y, Young MP

Publication type: Article

Publication status: Published

Journal: Experimental Brain Research

Year: 2003

Volume: 150

Issue: 3

Pages: 363-374

ISSN (print): 0014-4819

ISSN (electronic): 1432-1106

Publisher: Springer


DOI: 10.1007/s00221-003-1429-1

PubMed id: 12707744


Altmetrics provided by Altmetric