Welcome!

Welcome to the Face Perception Lab @ NTU, run by Dr Charles Or.

Research in our lab focuses primarily on face perception and how certain factors can influence the way we perceive faces. To answer these questions, we utilize methods from vision psychophysics, and cognitive science. Other research areas include motion perception, and confidence judgement.

If you’re interested in joining the lab, click on the Recruitment tab for more information.

If you’d like to read past works, click on the Publications tab for citations.

Eye movements and cultural variations

Culture has been well-documented within cross-cultural literature to influence a number of things – including where we fixate on faces. In this article, we ask if initial fixations on faces – i.e. the first few places we glance at – could differ, from culture to culture.

In experiment 1, 2, 4, and 5, East Asian and Caucasian participants completed the 1-in-10 face identification task. Participants were first shown a face, followed by a noise mask, and then 10 faces. When presented with the 10 faces, participants had to which one of the 10 faces matched the face they were shown prior to the mask. (See below for schematic procedure)

Image obtained from Or, Peterson, & Eckstein (2015).

Experiment 3 utilised famous faces as visual stimuli, whereas other experiments used faces of students from participating universities. This allowed the authors to determine if initial fixations from experiments 1 and 2 could be generalized to other types of faces – e.g. famous faces.

All in all, the results of the 5 experiments converged. Participants, regardless of ethnicity, show similar initial fixations at a featureless point, just below the eyes. The authors posit that initial fixations could be driven more by neural mechanisms, rather than culture, due to the strong functional role that a first glance has in face detection.

Reference

Or, C. C.-F., Peterson, M. F., & Eckstein, M. P. (2015). Initial eye movements during face identification are optimal and similar across cultures. Journal of Vision, 15(13), 12, 1-25.

 

Is colour useful in face categorisation?

Recognising faces as faces is an automatic, yet crucial process for everyday life. In this article, we ask how factors – in this case, colour – helps the categorisation process at a neural level.

Participants were shown coloured images of faces and objects, as well as grayscale images. These were presented in rapid succession, while participants wore an electroencephalogram (EEG).
When the task involved identifying shapes, neural responses unique to face images with colour was found. The authors found increased activity in the occipitemporal region in the right hemisphere of the brain after a 415ms latency.

Overall, the study’s findings suggests that colour contributes at later stages of processing, and aids face recognition when other visual information available are less ‘diagnostic’. That is, if a person stands beside a neon-coloured mannequin, you might register their face as a ‘face’ rather than the mannequin since humans are rarely neon-coloured.

 

Reference

Or, C. C.-F., Retter, T. L., & Rossion, B. (2019). The contribution of color information to rapid face categorization in natural scenes. Journal of Vision, 19(5), 1-20.