Fresh from the Lab: Jen Haensel, PhD student at the CBCD, on how postnatal environment shapes social development.
This week, we have a PhD student presenting her work. PhD students are notorious for getting their fingers dirty, which means that do work that is both very important and very time-consuming. Jen is no exception, but her big ready smile leaves no doubt about the level of satisfaction she gets from it.
She has been looking at faces. To be more precise, she has been looking at how people look at faces. And whether that differs under specific circumstances
Pictures of faces on screens vs. actual faces of real people
Western European culture vs. Eastern Asian culture
Babies vs. adults
Why would someone so clever spend three years of her life looking at this kind of question? Jen made it very clear: the real point of looking at cultural differences (besides that it gets you to travel around the world - editor's note) is actually to see what can be shaped by the environment and what is hard-wired in the brain from birth. In other words, what is written in the genes and what is due to the way we are brought up? Aka, the nature vs. nurture debate.
It is incredibly intriguing to analyse what is universally human versus what we learn through culture. It also has important implications for what and how we can support optimal development.
An eye-tracker in a lab setting.
Until recently, the only way of finding out about how people were looking at things was to bring them into a laboratory, place them in front of a computer with a connected eye-tracker, show pictures on the screen and let the eye tracker follow the eye-movements of the person. Matching the pattern of movement onto the shown pictures would then show how the participant observed the images. This sort of data has indicated that western caucasian and eastern Asian participants scan faces differently.
The image on the left is taken from an article by Blais and colleagues (read it in full here).
The blue blobs represent the areas that mostly eastern Asians looked at, while the red blobs cover areas looked at mostly by western caucasian participants. It seems that western caucasians tend to scan the eyes and mouth, while the eastern Asians focus more on the centre of the face.
Is the same thing true in a natural setting? Would you in someone’s eyes longer if they were in front of you, or on a picture? Imagine being on the tube and doing what Jen calls "face scanning," but what the rest of the world calls "staring at your face." That would be unacceptable, wouldn’t it?
SMI Glasses, similar to those used in Jen's study.
Technology now allows us to observe eye-movements in natural settings, which is what Jen has done. She’s used a portable eye-tracker, similar to the one you can see on the left. It seems impossible, but in those little glasses, there is a camera and some high-tech software that allows you to record both eye movements and the visual field of the person wearing them. Jen recruited 20 pairs of western caucasian residents in London, and 20 pairs of east Asian immigrants (who had not been in London for longer than 5 months). She invited them to the CBCD lab, sat them across a table, and asked them to introduce themselves and have a chat.
A semi-automatic face-tracking software was able to identify faces in the long stream of shots taken by the portable camera on the high-tech glasses, and determine where in the face the gaze was directed to.
Some of Jen's data. Eastern Asians look more at the face centre while western caucasians look more at the mouth.
Her initial data seem to indicate that in realistic settings, people scan faces differently across the globe. All participants looked more at their partner's faces when they were listening than when they were speaking. However, the two cultural groups focused on different parts of the face: the Asian population more on the face centre, the western caucasians looked more on the mouth. Jen is looking into this in more depth (which involves recruiting even more participants, and not only in London but also in Kyoto) and will keep us posted!
Jen is still testing babies. As you can guess, the challenges of testing small babies in natural settings is humongous. Imagine a baby wearing a portable eye-tracker, sitting still (ah! ah! ah!) and listening to her mother, who is talking to her while wearing a portable eye-tracker herself! And imagine that done in London and in Kyoto. Quite a task!
In fact, it turns out that London kids are kind of okay with it, meaning that Jen can get meaningful data for over 70% of the babies she tested. But the Kyoto kids are not as familiar with the idea of sitting in a highchair when mummy is just there, within reach. This made it a bit more difficult to collect data (so that poor Jen only had 36% usable data).
Jen making friends with a participant in London.
We have no doubt that Jen will find a solution for this challenge too! We look forward to hearing about how babies stare across the globe.