Cognitive Daily reports nearly every day on fascinating peer-reviewed developments in cognition from the most respected scientists in the field.
Greta Munger is Associate Professor of Psychology at Davidson College whose works include The History of Psychology: Fundamental Questions. Dave Munger is a writer whose works include Researching Online and The Pocket Reader. And yes, he is married to Greta.
The Stroop Effect was originally just a language effect: we're slower identifying the color text is printed in when the words themselves name different colors. In the 81 years since the effect was first observed, it's been applied to a variety of very different phenomena. In general, the effect is explained by automatic processing: when a process is automatic, it conflicts with the desired goal and so slows processing. In fact, the Stroop Effect is so robust that researchers now use it to determine if a process is indeed automatic.
Much research has focused on the issue of whether racial bias is automatic, but a team led by Jerzy Karylowski wanted to know if racial categorization itself is automatic, so they turned to the Stroop task. Would you be slower to identify the color a person's name is printed in if it conflicts with their race, regardless of your racial bias?
Recent research suggests that one of the reasons that as many as 97 percent of women and 68 percent of men experience food cravings is because of visual representations of food. When we picture food in our minds, our desire for the food increases. So why not just distract the visual system? One research team attempted just that, tempting volunteers with pictures of chocolate, and then distracting them with either a randomly changing visual image or an auditory task. The participants who watched the visual image experienced fewer food cravings.
I've attempted to reproduce the type of display these researchers suggest may distract you from your cravings (click on the image to start the animation).
The original research, however, didn't take into account whether participants were hungry. Perhaps if you're already hungry, the visual distraction won't help.
Family lore has it that my uncle was influential in instituting what is now a fixture in college education: student evaluation of college instructors. He was class president at the University of Washington in the 1960s, when tensions between students and the school administrators were high, and he suggested implementing one of the first student course evaluation systems in the nation as a way to address the problem. Needless to say, the idea caught on.
While college faculty complain unceasingly about the fairness of the now nearly universal student course evaluation system (I did it myself, back when I taught college courses), it has in general been shown to be a relatively reliable indicator of teacher effectiveness, correlating positively with other measures such as faculty and administrator evaluation, as well as actual student learning.
From the teacher's perspective, however, the students can't possibly have enough information to make an effective evaluation of their teaching. A college course represents just a tiny sliver of the total knowledge in a discipline, and even after a semester in a college course, students are in no position to make judgements that will impact a faculty member's entire career.
A 1993 study by Nalini Ambady and Robert Rosenthal found just the opposite: students actually need much less information to make judgements that accurately predict end-of-semester evaluations.
A number of studies have found cultural differences in visual cognition. For example, Takahiko Masuda and Richard Nisbett found that when Americans watch a short video clip of an underwater scene, they tend to recall the items in the foreground: the fish. Japanese people watching the same clip recall the items in the background: rocks, plants, and their relationship to one another.
A team led by Shinobu Kitayama showed people a frame with a line drawn inside. When asked to duplicate the line in a different-sized frame, Americans were better at drawing it the same size, despite the frame, while Japanese were better at scaling the line to correspond to the size of the new frame.
But why should such basic elements of perception vary between cultures? Most scholars have argued that social and learning differences between cultures are responsible for the difference, but Yuri Miyamoto, working with Nisbett and Masuda, wanted to explore another possibility: that these perceptual differences are due to the different physical environments in America and Japan.
The average 3- to 10-year-old girl in the U.S. owns eight Barbies. Only one percent of this group owns no Barbies. And every girl seems to go through similar stages with her Barbies -- first, adoration, next, ambivalence, and finally, rejection. By the time they're in middle school, most girls have either thrown out their Barbies or cut off their hair and amputated multiple limbs. These aren't just casual observations -- a 2004 study observed that while young girls identify with Barbie, 10- to 14-year-olds have distanced themselves from Barbie.
But what of the recent media hype suggesting that Barbie promotes an unhealthy body image? What of careful measurements finding that a life-sized Barbie would be over seven feet tall, thinner than most anorexics, and physically unable to menstruate? In 2003, Tonner Doll Company introduced the Malibu Emme, a more realistic adult doll whose body would translate into a size 16 dress. The idea was that this doll would promote healthier body image among girls. The doll never caught on among consumers, but the question remains: would a more realistic doll be a better role model for children?
One of these women can't recognize that the other is afraid, but when asked to express fear, is still able to produce a fearful expression. Can you tell which is which?
However, for extreme cases of epilepsy, one treatment is to surgically remove the amygdala, the area of the brain which processes, among other things, the sensation of fear. People who have had this surgery fail to recognize fearful facial expressions. A 1978 study in which experimenters stimulated patients' amygdalas directly with electrodes caused them to behave as if they were afraid.
But other efforts to induce fear reactions in patients whose amygdalas have been damaged or removed have had mixed results. One study found that people with damage to the amygdala could not recognize fear in faces, but could recognize fear in voices. Some studies measuring healthy individuals found that screams and yells do activate the amygdala, but others have found no impact of fearful speech prosody (the musical aspects of speech) on the amygdala.
Yesterday's post brings up an interesting question: How can you be unaware of having even seen an image, and yet be able to make reliable judgments about that image? That article is just one example of a variety of situations in which people can be unaware of seeing something, even immediately after being given a quick glimpse of it, yet behave as if they have seen it.
We discussed how visual images can be "masked" -- flashed quickly and then followed by another image which is displayed for a longer period. Though observers had no conscious recollection of seeing faces, they still could make accurate judgments about the attractiveness of the faces they had seen. Earlier experiments have found that the ability of the skin to conduct electricity as well as responses in the amygdala region of the brain can be affected by these masked images, again, with no conscious knowledge on the part of the viewer of having seen the image.
So how can our skin and brain respond to the image without our being conscious of seeing it? A team led by J.S. Morris developed a procedure to find out. Since the amygdala is activated during a fear response, they first conditioned volunteers to be afraid of a black and white photo of man with an angry facial expression. They used photos of four different men, two angry, and two neutral. These photos flashed randomly on the screen at intervals of around 20 seconds. When one (and only one) of the angry photos was displayed, a 1-second burst of white noise was played at a level of 100 decibels (loud enough to make you jump, but not to hurt your ears). Each face was shown six times.
How long does it take to decide if someone's attractive? It might be before you even know you looked.
Researchers can use a masking technique to show an image of a human face subliminally -- without the observer being aware of seeing it. To do it, they first show a scrambled face (39 milliseconds). Next, the face itself (13 milliseconds), a blank screen (13 milliseconds), and a cartoon face (39 milliseconds). I've tried to duplicate the technique using an animated GIF file, but I think it's beyond the capability of an ordinary web browser.
Did you see a human face? I had no trouble recognizing my son Jim in the animation, but you might be less aware of the image.
But Ingrid Olson and Christy Marsheutz were able to effectively mask images in the laboratory to try to measure how quickly humans can judge attractiveness. How did they do it?
Standup comics have long made vice president Dick Cheney the butt of their jokes, suggesting that he's never seen in public with the President because he inhabits some fortified underground bunker so as to avoid terrorists or some other unidentified threat, or that he's actually a cyborg, secretly controlling the government from his dark, hidden lair. But recent research in visual attention suggests that there might be another reason Cheney wouldn't want to be seen near the President. It may be that by standing next to a more famous person, your own appeal is diminished.
I'm actually only half-joking about this. Several studies, including one we've analyzed on Cognitive Daily, have taken a look at the relationship between attention and emotion: we respond quicker to emotional faces than neutral faces. Fewer studies have been conducted on the reverse phenomenon: when we search for an object, how do we react to it emotionally?
Take a look at this grid of colorized black-and-white photos: A team led by Jane Raymond showed volunteers similar grids and asked them to search for yellow males.
Babies as young as three months old will follow the eyes of an adult to look at the same thing the adult is looking at. This behavior makes sense from an evolutionary perspective: if a predator or other danger looms, we can learn from the actions of others (though it's unclear exactly what a three-month old would do to escape a ravenous bear).
But if the gaze-following behavior is really a survival adaptation, wouldn't we be more likely to follow someone's gaze if they also had a fearful facial expression? After all, if someone's glancing to the side with a cheerful smile, we don't expect they're looking at a jaguar ready to pounce. There's some evidence to support this notion. Several researchers have found that in photos of crowds, people are quicker to spot angry faces than happy faces.
A team led by Andrew Mathews showed volunteers photos of faces looking either to the left of the right, and with fearful or happy expressions. Then a letter appeared to one side of the face. While participants were faster at identifying the letter when it was on the side the face was looking at, they weren't any faster when the face had a fearful expression. So does this mean people never pay attention to the facial expression when following someone's gaze?
The TV show Extreme Makeover: Home Edition is a bit of a guilty pleasure for our family. I've never been quite sure why we like it: the plot of the show is always the same. We're introduced to a family which has undergone some terrible tragedy through no fault of their own: the father has been blinded by the gunshot of a thief while he was working overtime at a convenience store, or the daughter is undergoing treatment for chemotherapy, or the grandmother has adopted six troubled teenagers. Despite (and sometimes because of) their best efforts, the family's home has fallen into extreme disrepair.
Then Ty Pennington and his team ride in in a gleaming motor home, send the family off on a fabulous vacation, and demolish the old home, replacing it with a new, beautiful, state-of-the art structure guaranteed never to mold, mildew, or rust, in just 6 days. The kids are all given college scholarships, there are plasma HDTVs in every room, and everyone lives happily ever after. The whole thing seems rather like overkill, but at least the family seems deserving.
If we can't have such wonderful things, the show suggests, it's because we're not selfless enough, because we've caused our own problems through our lack of hard work or caring for others. But plenty of people are willing to work to help these "deserving" families. Pennington's gang mobilizes the entire community to give a single family the most luxurious home any of them have ever seen. Hundreds of volunteers work nearly nonstop for the six days of the project, sparing no effort or expense so this one family may live in luxury. Why do they do it?
Take a look at these two shapes. Which appears more "joyful"? Which appears fearful?
How about these shapes? Which is angrier? Which appears to be suffering more?
If you're like most people, the shapes that appear to be less stable (number 1 in the figures above) are also more fearful. Those that are rotated more from the vertical position (number 2 in the figures) are more suffering and less angry.
Assigning emotions to shapes is nothing new. In experiments as early as the 1940s, individuals have been found to consistently apply the same emotions to shapes in schematic cartoons: "angry" triangles and "loving" circles. But only one study had attempted to see if people consistently assigned emotions to static shapes based on the appearance of dynamic forces.
What's the best way to ensure that law enforcement officers don't abuse their authority and coerce innocent suspects into confessing? Yesterday we discussed research suggesting that a side-view videotape of a confession was more likely than a head-on view to result in an accurate assessment of whether that confession was voluntary or coerced.
But the Lassiter team's study was still open to some key criticisms. First, the study participants were all college students -- certainly not a typical jury demographic. Second, jurors don't see videotaped confessions in isolation -- when a confession is disputed, the prosecution and defense both offer additional arguments. Finally, the study only considered two video angles. Perhaps a different angle can produce even better results.
The team doesn't dispute these concerns, but instead points out that less-expensive studies using college student participants can be conducted to see if a line of research is valid. If those results are promising, then they can move on to more realistic scenarios.
College student Bradley Page dropped his girlfriend off in a park one evening, only to learn later that she had been murdered and buried in a shallow grave. Police investigating the death interviewed him about the incident, repeatedly asking him why he could have left her alone in that park. "It was the biggest mistake of my life," he responded in anguish. Eventually, the officers told him that witnesses had seen him near where the body was buried and that his fingerprints had been found on the murder weapon. These statements astonished Page, who hadn't even remembered leaving his apartment. There was good reason for his astonishment: both statements were lies.
Page, still credulous, asked the officers if it was possible for him to forget these details, to "blank it out." They told him such occurrences were common, and it might help to assuage his guilt if he told them how he might have killed his girlfriend. He obliged them, giving a hypothetical description of how he would have committed the crime. Two hours later, the police told him that they considered his statement to be a confession. Page, thoroughly surprised by this turn, immediately retracted the confession.
The confession was, however, admitted into court, and ultimately led to Page's conviction for manslaughter. Page's confession was recorded on audiotape and a complete transcript of the interrogation was made, but cases like this one have led to calls for videotaping of all police interrogations, so that juries can judge for themselves whether a confession is coerced. Videotaping has already been adopted in some U.S. states. But the research of G. Daniel Lassiter and his colleagues has suggested that even videotaped confessions can bias the jury: study participants who viewed reenactments of confessions from a face-on perspective were more likely to view the confession as legitimate than those who watched a side view.
If I like what I see, I'll receive 5 more issues (6 in all) for just $19.95. If I'm not completely satisfied, I'll simply write "cancel" on the invoice and owe nothing. The free issue is mine to keep.
Cognitive Daily reports nearly every day on fascinating peer-reviewed developments in cognition from the most respected scientists in the field.
The average 3- to 10-year-old girl in the U.S. owns eight Barbies. Only one percent of this group owns no Barbies. And every girl seems to go through similar stages with her Barbies -- first, adoration, next, ambivalence, and finally, rejection. By the time they're in middle school, most girls have either thrown out their Barbies or cut off their hair and amputated multiple limbs. These aren't just casual observations -- a 2004 study observed that while young girls identify with Barbie, 10- to 14-year-olds have distanced themselves from Barbie.
But what of the recent media hype suggesting that Barbie promotes an unhealthy body image? What of careful measurements finding that a life-sized Barbie would be over seven feet tall, thinner than most anorexics, and physically unable to menstruate? In 2003, Tonner Doll Company introduced the Malibu Emme, a more realistic adult doll whose body would translate into a size 16 dress. The idea was that this doll would promote healthier body image among girls. The doll never caught on among consumers, but the question remains: would a more realistic doll be a better role model for children?
