A study from the University of Maryland suggests that the key to understanding whether someone is being watched is to look for the eyes of their captors.
The researchers conducted the study to examine the eye movements of people who were being watched by a camera at a bar or hotel room.
The study involved four separate subjects, each of whom was wearing an infrared device, the researchers said.
One subject, an undergraduate student, sat in a room with a laptop computer in front of her.
She was then shown an image of a person she had never seen before, then asked to identify who it was.
She did this for three separate periods of time.
The second subject was seated at a table with a video camera in front.
She saw an image in front, then sat in front and was shown another image.
She also was shown a third image.
Then, after a third time, she was asked whether she had seen the third image and whether she could identify who she had been watching.
The third subject was a hotel guest.
After a fourth time, he was asked if he had seen or recognized the person in the third picture.
He did this again.
The fourth subject was not shown the third or fourth images and sat with his laptop in front for a third and final period of time, when the researchers wanted to get a better feel for the subjects facial movements.
In all cases, the subjects looked at the same image and were able to identify the person they had been viewing.
They also found that they were able the recognize the person who was in the room as their captor, although the subjects could not tell the difference between the two.
The research, published in the Journal of Experimental Psychology: General, found that the facial expressions and eye movements were similar for the three groups of subjects.
The team found that while people were more likely to identify their captiver, they were also less likely to recognize the other two people in the group.
“This indicates that the participants were unable to make the facial recognition discriminations that are crucial to a true recognition of the individual being observed,” the researchers wrote in their study.
“Thus, they did not show a clear distinction between the individuals they were observing.”
In the study, the participants had to read a series of three images before being asked to tell whether they recognized the individual in the picture or not.
The participants were also asked to estimate the number of times they had seen and recognized the subject.
The final image showed the participants with their eyes closed.
The group that was shown the first image of the group was more likely than the others to recognize that person.
The people who had seen their captivors were also more likely in their estimation to say that they had recognized the group that they believed they were seeing.
“In other words, the facial identification did not depend on any specific visual cue, like eye movements,” the authors wrote.
“Rather, it depended on the participants’ internal state, which is a measure of the degree to which they were aware of the person being observed and the ability to discriminate the facial features of that individual,” the study noted.
“As such, these findings suggest that the ability of individuals to identify other individuals as their own faces, even though they may be in different places, might depend on their experience of facial identity and social dominance, as well as on their ability to form judgments about social status and social cues, such as others’ eyes.”
The study is the latest in a series to look at how human beings perceive faces.
Researchers have been studying the brains of chimpanzees, elephants and people who have been photographed with video cameras for more than 20 years.
The first study of facial recognition in humans was published in 2003 and focused on the ability people to recognize faces.
The work of that study was published by two University of California, Berkeley professors.
Since then, several studies have looked at other aspects of human facial recognition, including the ability humans to recognize someone in a photo and the difficulty in discriminating between different facial features, such the eyes and mouth.