reasoning

Ducklings are rather well-known for their ability to imprint on someone (usually their mother) or something shortly after hatching. Researchers at the University of Oxford were interested in understanding more about learning and memory in ducklings. Specifically, they wanted to know if a duckling simply remembered what they saw or if they were capable of more complex cognition involving determining whether objects had the same or different qualities. After hatching, they placed ducklings in an enclosed space that contained either identical or different red shapes attached to a string that…

Suppose your organization is interviewing candidates for an important job. Would it be better for one trusted person to have an extended interview with them, or for several people to talk to them for less time? How many people would you need to conduct the interviews? Would three be enough? Would ten be too many? If ten is good, wouldn't twenty be even better? We've discussed thin-slicing studies before -- the idea that a few brief exposures to an individual can give just as accurate an impression of key traits as much more extended interactions. For judging sexual preference in men, a 10-…

Take a look at this video from last night's episode of Jon Stewart's "The Daily Show." If you'd like, you can skip past all the political snark to the 4:47 mark to watch Jon bring cognitive psychology into prime time (or at least latenight cable)! That's right; you saw it: Jon Stewart mentioned the psychological concept of "object permanence" on national TV. Object permanence was introduced by Jean Piaget as a way of measuring the growing cognitive ability of children. Three-month-olds don't have it; most 6-month-olds do. More recently, researchers have investigated similar milestones in…

As an undergraduate, at my school it was practically a requirement to steal silverware from the campus cafeteria. There were students who'd commandeered full sets of china. The desk clerk at my dorm used to say that the only thing we were learning from our college education was "how to steal." Somehow it didn't seem wrong to us to steal from the cafeteria (though I drew the line at a single setting of silverware). Plus, we'd heard that at other schools, students used the cafeteria trays as sleds after the first winter snow. At least we weren't doing that (though arguably this was only because…

Imagine your neighbor has a dog that regularly escapes her yard. One day you see the dog escape and return it to her. She thanks you by giving you a piece of delicious home-made apple pie. This happens several days in a row. Then one day when you return the dog, there's no pie, no thanks, and no explanation. Would you return the dog the next time it escapes? You might be disinclined. But what if there had never been any reward? Wouldn't returning her dog be the right thing to do? Children as young as 14 months old will spontaneously help others for no reward. But a 1973 study of 3- to 5-year-…

How did you decide to read this post? You might have seen the headline in an RSS reader or noticed it on the ScienceBlogs home page. Maybe someone emailed or tweeted the link to you. But you still had to make the decision to actually read it. How do you know when you made that decision? In 1965 H.H. Kornhuber and L. Deeke found that brain activity precedes a conscious choice (voluntarily pressing a button) by 500 to 1,000 milliseconds. But in 1983 a team led by B. Libet found that when people were asked when they consciously decided to press a button, they said their decision came about 200…

[This post was originally published in September, 2007] Here's a task that four-year-olds can do but three-year-olds have some trouble with. Imagine Sally in the picture below is playing with a ball. She puts the ball in the box and goes to the kitchen to get a drink. While she's gone, Bill takes the ball out of the box and puts it in the bucket. When Sally returns, where does she look for the ball? Most three-year-olds will say Sally would look in the bucket, apparently failing to realize that Sally doesn't know anything about what Bill did while she was gone. Some researchers have…

Implicit attitudes and associations can tell us a lot about a person. It's a way to find out if they might have a racial or gender bias, and recently there has even been some work suggesting that an implicit association test can tell us whether someone is lying -- it's called the autobiographical Implicit Association Test (aIAT). Here's how it works: Suppose you're an American soldier and you want to know if an Afghan you've captured is really a member of the Taliban, despite his assurances that he supports your side and only carries a Kalashnikov for self-defense. You fire up the aIAT…

[Originally posted in April 2007] Cognitive decline as we age is all over the news lately. "Brain fitness" products are available for cell phones, Game Boys, and Xboxes, all designed to prevent the natural decline in cognitive ability as we age. There's even a significant body of work suggesting that this sort of product really can work. But some of the brain games can be dull, repetitive work: memory tasks, number games, and optical illusions, while endlessly fascinating to cognitive scientists, might be less appealing to the general population. Researchers Helga and Tony Noice believe that…

When school budgets are cut, programs in music and the arts are often the first to get axed. While this makes a certain amount of sense because music isn't always considered "essential" to education, recently in the U.S. we're starting to see another justification for cutting music out of schools. The No Child Left Behind Act demands that students meet a certain basic level of academic success, or a school's budget can be cut. "Extras" like music classes and recess only distract from the primary goals of learning English, math, science, and history, some say. But does music participation…

My computer has over 5,000 songs on it -- 16.2 days' worth, according to my music-playing software. So how do I pick what song to listen to? More often than not, I just shuffle the whole list and play whatever album shows up on top. But if I'm in the car listening to the radio, I switch between the 10 or so local stations I've programmed in until I hear a song I like. I seem to be more likely to rely on my own judgment when I have fewer choices. Some researchers have found similar effects with buying decisions: shoppers with just a few flavors of jam to choose from are more likely to buy than…

It's pretty obvious to most people that the two shoes in this picture are the same size: But if you actually took a ruler to your computer display it would show that the image of my right shoe is nearly twice as wide as the image of my left shoe. Young children will mistakenly say that the real left shoe is smaller than the right shoe; it's only gradually that we learn to take the context of the photo into account and conclude that the shoes are the same size: the shoes appear to be a matched set; the left shoe is a bit out of focus, the railing to the left shows that the left shoe is…

[This article was originally posted in December, 2006] I'm not bitter about this, honest I'm not, but it does often seem that people who know you very well end up buying really lousy gifts. What I really want to find out is this: why do they do that? It turns out, market researchers want to know, too. How can they have a prayer of selling people things they don't want when people can't even convince their loved ones to buy them things they do want? Davy Lerouge and Luk Warlop have designed a clever study to examine this very issue. They wanted to know whether couples who've been together for…

The SNARC effect is a fascinating phenomenon (and no, it has nothing to do with cheeky one-off blog posts). When asked to recognize numbers, people react faster with their left hand for low numbers, and faster with their right hand for high numbers. Take a look at this graph: This shows the results of an experiment led by Samuel Shaki: Twelve Canadian university students were shown a series of single-digit numbers. Their task was simple: as quickly as possible, press one button if the number is odd, and another button if the number is even. This graph charts reaction time of the right hand…

When you selected the college or university you planned to attend, how did you do it? Did you read narratives offered by college guides? Did you compare relevant statistics such as the student/teacher ratio and percent of students who went on to graduate school? Did you listen to the advice of older friends who had attended the school? Or did you visit the school in person? And which of these factors had the most impact on your decision? For many students, the campus visit is the deal-maker (or breaker). Here at Davidson I've met many students who said they had been undecided, but when they…

Imagine the following scenario: Matthew is playing with his new kitten late one night. He is wearing only his boxer shorts, and the kitten sometimes walks over his genitals. Eventually, this arouses him, and he begins to rub his bare genitals along the kitten's body. The kitten purrs, and seems to enjoy the contact. How wrong is it for Matthew to be rubbing himself against the kitten? Or how about this one: You find a wallet with several hundred dollars in cash, along with credit cards including an American Express Gold Card and ID locating the owner's home in the richest neighborhood in town…

Several studies have confirmed this bizarre proposition: If you're taking a test of rote memorization, like words from a list, move your eyes from side to side for about 30 seconds before you start. Really. Researchers have found, with relative consistency, that if you saccade from left to right and back several times before a test of simple recall, you're likely to do better. Why? It may be that this quick activity helps facilitate interaction between the brain hemispheres. Since split-brain patients have more difficulty recalling words than people with normal brains, any activity that…

Take a look at this astonishing (and adorable) video demonstrating how a baby acquires object permanence. At 6 months old, the baby can see and reach for an object, but as soon as it is hidden, she doesn't seem to realize it's there. The baby is interested and excited by the objects, but when they're not visible, it's as if her memory has been wiped clean. By 10 months, the phenomenon has vanished and the baby behaves like any older child would, clearly realizing that the book is hidden under the blanket and immediately uncovering it. But 10-month-olds will make another error. If you have…

Take another look at this picture of the Rokeby Venus from last week's post on mirrors in art: Now, imagine you're actually in the room with Venus, as depicted in this painting. You suspend your astonishment long enough to conduct a quick test of the principle of how a flat mirror works. Consider what would happen to Venus' face in the mirror as you approach it. As you walk towards the mirror, would the proportion of the reflection taken up by Venus's face increase or decrease? In the painting, the face takes about 2/3 the width of the mirror. Would that proportion get bigger or smaller as…

The Rokeby Venus by Diego Velázquez is a good example of a very common illusion in many paintings: Most viewers would say this picture depicts a woman viewing her own reflection in a mirror. But based on the orientation of the mirror, it's actually physically impossible for her to see her own reflection. Since we can see her face, then if she could see face in the mirror, her head would have to be positioned between us and the the mirror. At best all she would be able to see is us (or rather, the painter painting her picture). Art critics have suggested that there's another problem with…