The Human Brain Subliminally Judges the Trustworthiness of Faces: Digital Implications?

Who you gonna believe: your instincts or your lyin' eyes?

Research demonstrating that the brain makes subliminal judgments about trustworthiness based on responses to certain visual clues is perhaps not all that surprising. After all, for the several tens of thousands of years prior to Big Data, mankind did not have a lot to go on when it came to telling friend from foe so something had to help support the propagation of the species.

If a furrowed brow was one of those 'watch out!' tells, well, thanks for the tip. But it is the implication for extrapolating such knowledge into useful intelligence for the digital era that bears further examination. There are already reports of billboards that can 'read' us as we pass by, of programs that relentlessly sift our personal data for clues in order to increase the chance that we'll respond positively to a sales pitch or election campaign. The interactivity of our electronic devices is making such analyses both more sophisticated and ubiquitous.

This takes us into the realm of fairness and rights and liberties and privacy and personal and commercial. Where does one end and another begin? Should there even be such boundaries and if so, who should set them? Society is currently torn between its desire to monetize anything it can and the need to preserve some semblance of personal freedom. Where that balance will be struck is by no means certain. JL

Ian Sample reports in The Guardian:

Even though people might not have conscious awareness, they might move back very subtly when perceiving an untrustworthy face
The human brain can judge the apparent trustworthiness of a face from a glimpse so fleeting, the person has no idea they have seen it, scientists claim.
Researchers in the US found that brain activity changed in response to how trustworthy a face appeared to be when the face in question had not been consciously perceived.
Scientists made the surprise discovery during a series of experiments that were designed to shed light on the the neural processes that underpin the snap judgments people make about others.
The findings suggest that parts of our brains are doing more complex subconscious processing of the outside world than many researchers thought.
Jonathan Freeman at New York University said the results built on previous work that shows "we form spontaneous judgments of other people that can be largely outside awareness."
The study focused on the activity of the amygdala, a small almond-shaped region deep inside the brain. The amygdala is intimately involved with processing strong emotions, such as fear. Its central nucleus sends out the signals responsible for the famous and evolutionarily crucial "fight-or-flight" response.
Prior to the study, Freeman asked a group of volunteers to rate the trustworthiness of a series of faces. People tend to agree when they rank trustworthiness – faces with several key features, such as more furrowed brows and shallower cheekbones, are consistently rated as less trustworthy.
Freeman then invited a different group of people to take part in the experiments. Each lay in an MRI scanner while images of faces flashed up on a screen before them. Each trustworthy or untrustworthy face flashed up for a matter of milliseconds. Though their eyes had glimpsed the images, the participants were not aware they had seen the faces.
Even so, the brain scans revealed that the amygdala responded differently to subliminal images of trustworthy and untrustworthy faces. Some regions of the amygdala reacted to how untrustworthy a face was, while other regions seemed to register the overall strength of the judgment, becoming more active only when a face was either very trustworthy or very untrustworthy.
Freeman said the biggest question now was whether the brain activity altered how people behaved. "Even though people might not have conscious awareness, they might move back very subtly when perceiving an untrustworthy face, but that is still unknown," he said. Details of the study appear in the Journal of Neuroscience.
Previous work has shown that the amygdala reacts to scary subliminal images, but to find that the structure made judgment calls on trustworthiness was unexpected.
"The social cues for trustworthiness are considerably more subtle and complex than a simple, fearful expression on a clearly emotional face. It suggests that the amygdala's processing of social cues outside awareness may be more extensive than we thought ," Freeman said.
"The findings are surprising because they show that face evaluation can be done without perceptual awareness," said Alexander Todorov, professor of psychology at Princeton University. "Even if we are unaware of perceptual information, our brain, in this particular case the amygdala, is capable of processing this information."