Cognitive Daily reports nearly every day on fascinating peer-reviewed developments in cognition from the most respected scientists in the field.
Greta Munger is Professor of Psychology at Davidson College whose works include The History of Psychology: Fundamental Questions. Dave Munger is co-founder and president of ResearchBlogging.org and a writer whose works include Researching Online. And yes, he is married to Greta.
Last week we asked readers to rate two hypothetical job candidates for a communications assistant position in a large neuroscience lab. The task seemed to pit education against experience. Everyone saw some version of these two resumes:
(click for a larger image)
Emily was Magna Cum Laude at Harvard, while Suzanne was an average student at a regional state college. But Emily appeared to have never held a paying job, padding her resume with activities like "Botanical Garden Society President" and "Varsity Tennis." Meanwhile, Suzanne had held an impressive internship and had three years of related job experience.
Most respondents -- nearly 80 percent out of over 800 who completed the survey -- selected experience over education, preferring Suzanne over Emily.
But that wasn't the real purpose of our study. We were actually interested in a subtler point: should you put more effort into the overall look of your resume, or into proofreading to fix typographical errors? Respondents actually only saw one of three possible pairs of resumes. Each pair contained the same information, but one pair was full of typos (here's an example), while another pair was badly formatted, with ugly fonts and inconsistent layout (here's an example). The final group of respondents saw attractive and accurate resumes. So which resumes were rated highest? Here are the results:
After taking a first look at last week's survey responses, I realize there's one more question I should have asked. So if you have a couple minutes, whether or not you participated last week, could you respond quickly to this short survey? You'll just be asked to look at two resumes and answer two quick questions about each.
A few years ago we discussed a fascinating study which appeared to show that the main reason we stop eating at the end of a meal isn't because we "feel" full. Instead, we simply see that we've finished eating the food in front of us, so we stop. We don't eat more an hour later because we remember we just ate.
In that study, led by Paul Rozin, experimenters provided two amnesic patients with two meals separated by just 15 minutes. They both did not recall eating the previous meal due to their medical condition, and each of them ate both meals as if they hadn't had anything to eat.
But maybe amnesia has additional subtle effects. The condition is usually caused by severe brain trauma, so it's possible that amnesics (or the particular amnesics in the study) have also lost their ability to detect fullness. Could that explain their seemingly bizarre behavior?
A team led by Suzanne Higgs identified two new patients who had a similar type of amnesia: They could not form new long-term memories, although their old memories and short-term memory were intact. They repeated Rozin's multiple-meal study and found the same result: while people with normal memory refused a second lunch, both amnesic patients ate two full meals, consuming nearly 2,000 calories while the others ate only about 700.
But in a separate experiment, volunteers (including the two amnesics) were presented with small samples of four different foods (a cookie, potato chips, rice pudding, and sandwiches) for tasting. They were asked to rate each food for taste, texture, and desire to eat. Next they were given a meal-sized portion of the sandwiches and asked to eat as much as they liked. Finally, they rated each item once more on the same scale. Here are the results:
What's your first reaction on seeing this picture of Nora? Are you excited because she appears to be excited? Or do you react to her intent? Perhaps you think she's cute, or maybe even sarcastic. Ultimately you might have all of those reactions.
There's no doubt we're exceptionally fast at responding to faces, and to the emotions they convey. But reacting appropriately, especially when a face signals danger, could be the difference between life and death.
These two ways of reacting to a facial expression correspond to two possible intentions of an expression: to elicit an emotion in someone else, or to express your own emotional state. The result, for the other person, isn't always the same. For example, if you simply mimick the emotion of an angry face, then you too would be angry. But if the angry person was stronger or better-armed than you, you might recognize their anger and become afraid, not angry. So which response comes first?
Kirsten Ruys and Diderick Stapel believe they have devised a way to find out. They asked students to watch movies that quickly flashed emotional faces at them -- so fast that the facial expressions couldn't be consciouly judged. The faces were flashed at two different speeds, illustrated in this video:
The students were instructed to focus on the cross in the center of the screen and react as quickly as possible, indicating when a picture flashed to the left or right of the cross. As you can see in the slowed-down version (which the students never saw), the face flashed very briefly before being masked by a black-and-white rectangle. (Yes, that's me, doing my best to look "angry.") In the "quick" version, the face stayed on-screen for 120 milliseconds. In the "super quick" version, it appeared for just 40 milliseconds. The students were divided into 8 groups, who saw one of four emotions (Anger, Fear, Disgust, or Neutral) at either quick or super quick speeds.
When I'm writing a post for Cognitive Daily (or doing almost any kind of writing, for that matter), I try to keep outside distractions to an absolute minimum. I even have an application on my computer that shuts off all access to the internet for a specified period of time. I find most music distracting, but sometimes I'll play a Mozart piano concerto, which seems to help focus my attention (see here for a possible explanation).
Some people, however, seem to be able to be incredibly productive despite a huge number of distractions -- Twitter status updates, email, crying babies, you name it. Indeed, some people can't work well if things are too quiet. For them, uninterrupted silence is more distracting than cacophony.
But whatever their working environment, it's clear that some people are simply better at focusing on the task at hand. What makes people's minds more or less likely to wander? Several studies point to working memory capacity as the key. While on average people can keep about 6 or 7 words or numbers in memory, capacity varies from individual to individual. People with higher working memory capacity tend to do better on tasks like the sustained attention to response task (SART) which demand focused attention to a task. We discuss the SART in more detail here, with a video example.
Working memory might seem unrelated to such a simple task as SART: Usually you're asked to do something like respond only to words NOT beginning with the letter "P", while dozens of words flash by and only the occasional "P" word. You've only got to focus on one thought at a time -- why should it matter whether your working memory capacity is 5 or 8?
There's a lot of advice online about what makes a good resume, and in these tough economic times, getting a job is tougher than ever.
So this week, I thought we'd test some different resumes and see which factors are most important in picking a good candidate. You'll be asked to read two resumes very carefully, then answer a few questions evaluating each candidate. I've changed just a few items on each resume, so make sure you read them closely. Then next week we'll see which factors matter the most.
As usual, the study has just a few questions, and should only take a few minutes to complete. There is no limit on the number of respondents. You'll have until Thursday, March 5 to complete your response. Don't forget to come back next Friday for the results!
Last week, we presented research by Miranda Scolari's team about visual expertise and visual short-term memory. Their conclusion: "experts" don't have a larger visual memory capacity than non-experts, they just have the ability to process more details. Scolari's team was working under the assumption that all humans (or at least all the students in their experiment) are face-recognition experts.
It's true: we're amazingly good at recognizing faces we've seen before. Think how much easier it is to remember a face you've seen than it is to remember the name that goes with the face. But surely we can be visual experts in other types of objects besides faces, right? Otherwise Scolari's study would apply to faces and nothing else.
To find out, a team led by Kim Curby did a similar study, using car experts instead of face experts. They tested 36 volunteers on their knowledge of cars by showing them photos of cars from two different years; they had to say whether the cars were they same or different model. The highest scorers were the experts, and the lowest scorers were "novices."
Curby's memory-test was similar to the example I showed you last week:
Take a look at this quick video. You'll see a set of six small images, arranged in a circle, for 1 second. Then the screen will go blank for 1 second. Finally, one image will reappear in the place of one of the first six pictures. Your job: indicate whether the final image is the same or different as the image that originally appeared in that same spot.
But there were a few differences. First, Curby's team asked viewers to repeat a pair of numbers like "7 2" while they watched the video. Second, half the time the viewers saw faces, and half the time they saw cars (both of which sometimes appeared upright, and sometimes upside-down). Finally, viewers saw the images for varying lengths of time: either 0.5 seconds, 2.5 seconds, or 4 seconds, instead of the 1-second viewing time in my example and the Scolari et al. study. Here are the results for faces:
What is so mesmerizing about pointillist paintings like Seurat's Sunday Afternoon at La Grande Jatte? At first, we're impressed by the technical virtuosity of the work. It's an immense painting that Greta and I visited many times when we were in college in Chicago (and now, whenever we return for a visit):
As you can see even in this reduced image, the painting is composed of tiny dots. But what you may not notice is that the dots in a given region of the painting aren't all the same color. Take a look at this detail:
The leaves in the trees range from red to yellow to green to blue, and the water includes blues, purples, greens, and yellows.
When you visit the painting in person, you might get the impression that the colors actually change as you approach or move away from the work. Of course, they can't really be changing. But vision scientist Pascal Mamassian believes that what you experience as you view a pointillist work might be similar to an effect described by Patrick Monnier and Steven K. Shevell. Take a look at this image:
One of my most vivid memories from middle school was in English class. The class wasn't paying attention to the teacher -- we were chattering during "work time" and she wanted us to stop and return to a full-class lesson. So she shouted "SEX!" We all shut up immediately and stared at her in disbelief. Then she said, in a calm, normal voice: "Now that I've got your attention ..." and proceeded with her lesson. It worked great -- except for one thing. I have no recollection of what she actually taught us that day.
This brings up an interesting point: Teachers are often tempted to bring up interesting but irrelevant details (like SEX) in order to maintain student interest in a lesson. But does this actually help students learn the material better? Several studies indicate that it does not. Adding extraneous, unrelated anecdotes can actually distract students from the task at hand and lead to poorer recall, even if they are more "interested" in the material.
But a secondary question about extra details in course materials has yet to be answered: Is it the fact that extra details are present at all which leads to poorer learning? Or does the kind of extra details matter? Are students "seduced" by sexier examples, therefore missing the primary point of the lesson?
A team led by Richard Mayer created two different versions of a lesson on how viruses attack humans. In one version, each major point of the lesson was interrupted by an interesting anecdote such as this one:
A study conducted by researchers at Wilkes University in Wilkes-Barre, Pennsylvania, reveals that people who make love once or twice a week are more immune to colds than folks who abstain from sex. Researchers believe that bedroom activity somehow stimulates an immune-boosting antibody called IgA.
In the other version, boring anecdotes were used instead:
When a freshman at Penn State too many years ago to count, the intro psychology prof did an amazing demonstration. I wonder if anyone knows the answer to this which I have long forgotten.
He said he had written the numbers 1 through 5 in random order on a piece of paper. He then asked the very large class to read his mind and write down his number order.
When the class compiled the answers, more than 50% of the class had his order, and so proved that telepathy was possible!!!
The class was ecstatic, until he then told us that humans more often than not arrange those numbers in that particular sequence that he had.
Does anyone know what that sequence order is?
I have puzzled over this for years since.
I thought we might do Bobbysoxer a favor by uncovering the number sequence, if indeed it exists. I was skeptical: half the class? A sequence of five items, in random order? Since there are 120 possible unique sequences of the numbers 1 through 5, a random distribution of responses would mean fewer than one percent of answers would be in any given order. Chances that HALF the responses would be the same seem remote.
That's not to say that responses will be truly randomly distributed. But I doubted that any single combination of digits would even approach 50 percent.
Our survey asked respondents to randomly arrange the digits 1 through 5 -- and also 1 through 4, and 1 through 3. Perhaps with a smaller range of choices we'd get something approaching Bobbysoxer's memory of the event.
First let's take a look at the distribution of responses for the digits 1 through 5. How "random" were our answers?
Take a look at this quick video. You'll see a set of six small images, arranged in a circle, for 1 second. Then the screen will go blank for 1 second. Finally, one image will reappear in the place of one of the first six pictures. Your job: indicate whether the final image is the same or different as the image that originally appeared in that same spot.
In principle, this should be an easy task, right? Your visual working memory can hold around six items at a time, so it shouldn't be hard at all to remember if the new picture is the same as the one it replaced. So, is the final picture the same as the one it replaced?
Let's make this a poll (if you don't know, just guess):
If we're very accurate at this task, then one answer (the correct one) should dominate. If we're not very good at it, answers should be closer to 50-50.
In fact, visual memory is a bit more complicated than that. What constitutes a single item in your memory? Is it a whole face? Or does each portion of the face count as a separate item to be remembered?
In a 2007 study, Kim Curby and Isabel Gauthier found that "experts" seem to have a larger visual working memory in their area of expertise than non-experts. (Nearly all humans are experts at recognizing faces, unless the faces are upside-down). But a team led by Miranda Scolari wasn't convinced. Maybe the distinction between expert and non-expert isn't the size of working memory, but how detailed it is.
I had a newspaper route up until I was in the ninth grade, and what I dreaded about the job was going door-to-door collecting subscription fees. The worst part was probably the odors in some of the houses. One house emanated a toxic mixture of Lysol, alcohol, pet dander, and cigarette smoke. These people inevitably were out of cash, so I had to return again and again until I finally was able to negotiate payment -- sometimes months overdue.
But maybe the smell was prejudicing my judgment. Lots of people couldn't pay me right away. Why should I only hate the ones with drinking/pet/smoking/air freshener problems? Other than the fact that they had all those problems, they weren't any better or worse than anyone else (aside from the nice old ladies who baked me cookies I could smell a half-block away).
Hmm... come to think of it, there's a lot a smell can tell you about a person. Are they overperfumed, undermouthwashed, sweaty, smoky, or infused with motor oil? Different scents clearly have different meanings.
But some smells are too subtle to be detected. You might not be able to discern your wife's perfume by the end of the day, although traces are still present. What if someone else was wearing her perfume, still at levels you don't consciously notice? Would that affect your impression of them?
We know from studies on subliminal images and sounds that even when we're not conscious of these things, they can affect our judgments and actions. But researchers have had difficulty finding any effect of odors that we can't consciously identify. A team led by Wen Li saw procedural problems in those early studies: An odor that one person can't detect might still be obvious to someone else. Even the same individual might perceive an odor sometimes and not others ("I thought I smelled smoke, officer!").
In honor of President's Day in the U.S., I bring you this work of "art," generated on the basis of a survey of 1,001 Americans' preferences about art:
The work was created to embody the survey responses. The respondents were asked questions like "what is your favorite color" and "would you prefer paintings of outdoor scenes or indoor scenes." The artists, Vitaly Komar and Alex Melamid, then tried to paint as many as possible of the survey responses into the scene.
Thus, blue dominates in this painting of an outdoor landscape. There are wild animals (as opposed to pets), and a family group (rather than an individual). George Washington is present because people said if famous people were depicted, the preference would be for historical figures rather than contemporaries.
The same survey was repeated around the world. Interestingly, the results were nearly the same almost everywhere. You can see the full set of paintings here.
As usual, the survey is brief, and should take only a minute or two to complete. You have until Thursday, February 19 to respond. There is no limit on the number of responses. Don't forget to come back next Friday for the results.
How do you decide how dangerous a sex-offender is? Certainly all cases of sexual assault are appalling, but clearly some incidents are worse than others. In some places, teenagers who photograph themselves naked and send the pictures to their friends can be prosecuted as purveyors of child-pornography. While we may want to intervene in these cases, surely the action shouldn't be as drastic as when we're dealing with an adult who's a serial child rapist.
There are miles of gray area between these two extremes, and psychologists are often called on to make the tough judgment of how dangerous a individual might be. One common test is to attach a monitor to the offender's penis and then show them images of children and adults. In principle, true pedophiles will be more aroused by the children's pictures. But a convict applying for parole has a good reason to try to fake his response, and some people are inevitably misclassified, with potentially disastrous results.
Other methods, such as the Implicit Association Test, have also been tried, but these are also potentially subject to manipulation. So a team led by Anthony Beech decided to see if a different test could be used: The Rapid Serial Visual Presentation test, or RSVP. As we discussed on Monday, in an RSVP test, a distracting word or image is presented in a series of similar displays. If the viewer's attention is attracted by the distractor, he or she is more likely to miss a later image. As an example I've modified Monday's task. Can you spot the words naming a color (like blue, red, or green)? Ignore all the other words.
Instead of words, Beech's team used photographs. They recruited convicted child molesters and other non-sex-related felons (from British prisons) to volunteer for their test. The volunteers were looking for four types of pictures: children or animals (the distractors), and chairs or trains (the targets). The rest of the pictures were neutral scenes or objects. The photos flashed by at a rate of ten per second, in sets of 11. At a random point one of the distractors would appear, just like in the example above. Two to three images later, the target appeared. Then respondents had to say what the distractor was, what the target was, and which direction the target was facing (left or right).
A couple hours ago I posted a quick poll, in what might be construed as an unbiased fashion. I simply asked respondents for their sexual orientation, offering a wide array of choices ranging from "straight" to "mostly gay" to "gay" to "other."
In fact, my poll was biased -- not because the question itself was slanted, but because of the way respondents were recruited: I titled the post "Are you homosexual?" Potential respondents who are homosexual or who don't have traditional sexual preferences are more likely to be interested in the question, and therefore more likely to respond. How do I know this biased the sample? Because I collected similar data last week in the Casual Fridays survey about romantic gifts. In that survey, women reported same-gender partners 5.7 percent of the time, and men reported same-gender partners 3.7 percent of the time.
I posted the poll because I had seen a similar poll on Twitter: Bruce Wagner asked "How Gay is Twitter?" and linked to his own poll. I suggested Bruce's selection of responses would be biased, and he challenged me to prove it. Here's the evidence:
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.
What's your first reaction on seeing this picture of Nora? Are you excited because she appears to be excited? Or do you react to her intent? Perhaps you think she's cute, or maybe even sarcastic. Ultimately you might have all of those reactions. 
