Archive for the 'Perception' Category

Internet use can “boost” brain function

October 21, 2009

Science Daily reports:

UCLA scientists… found that middle-aged and older adults with little Internet experience were able to trigger key centers in the brain that control decision-making and complex reasoning after just one week of surfing the Web.

The findings, presented Oct. 19 at the 2009 meeting of the Society for Neuroscience, suggest that Internet training can stimulate neural activation patterns and could potentially enhance brain function and cognition in older adults.

Is multitasking hazardous to your cognition?

August 25, 2009

CNN reports:

A new study suggests that people who often do multiple tasks in a variety of media — texting, instant messaging, online video watching, word processing, Web surfing, and more — do worse on tests in which they need to switch attention from one task to another than people who rarely multitask in this way.

Specifically, heavy multitaskers are more easily distracted by irrelevant information than those who aren’t constantly in a multimedia frenzy, according to the study in the Proceedings of the National Academy of Sciences.

One reason may be because the multitaskers tend to retain the distracting information in their short-term memory, which affects their ability to focus, compared with people who don’t check their e-mail while talking on the phone and sneaking in some online shopping.

The article is available here (subscription required).

New study suggests we learn more from successes than from failures

August 11, 2009

Science Daily reports:

If you’ve ever felt doomed to repeat your mistakes, researchers at MIT’s Picower Institute for Learning and Memory may have explained why: Brain cells may only learn from experience when we do something right and not when we fail.

In the July 30 issue of the journal Neuron, Earl K. Miller, the Picower Professor of Neuroscience, and MIT colleagues Mark Histed and Anitha Pasupathy have created for the first time a unique snapshot of the learning process that shows how single cells change their responses in real time as a result of information about what is the right action and what is the wrong one.

“We have shown that brain cells keep track of whether recent behaviors were successful or not,” Miller said. Furthermore, when a behavior was successful, cells became more finely tuned to what the animal was learning. After a failure, there was little or no change in the brain — nor was there any improvement in behavior.

Language and cognition

July 21, 2009

NEWSWEEK reports:

[Stanford University psychologist] Lera Boroditsky… has long been intrigued by an age-old question whose modern form dates to 1956, when linguist Benjamin Lee Whorf asked whether the language we speak shapes the way we think and see the world. If so, then language is not merely a means of expressing thought, but a constraint on it, too…

…In a series of clever experiments guided by pointed questions, [Boroditsky] is amassing evidence that, yes, language shapes thought. The effect is powerful enough, she says, that “the private mental lives of speakers of different languages may differ dramatically,” not only when they are thinking in order to speak, “but in all manner of cognitive tasks,” including basic sensory perception. “Even a small fluke of grammar”—the gender of nouns—”can have an effect on how people think about things in the world,” she says.

Language even shapes what we see. People have a better memory for colors if different shades have distinct names—not English’s light blue and dark blue, for instance, but Russian’s goluboy and sinly. Skeptics of the language-shapes-thought claim have argued that that’s a trivial finding, showing only that people remember what they saw in both a visual form and a verbal one, but not proving that they actually see the hues differently. In an ingenious experiment, however, Boroditsky and colleagues showed volunteers three color swatches and asked them which of the bottom two was the same as the top one. Native Russian speakers were faster than English speakers when the colors had distinct names, suggesting that having a name for something allows you to perceive it more sharply. Similarly, Korean uses one word for “in” when one object is in another snugly (a letter in an envelope), and a different one when an object is in something loosely (an apple in a bowl). Sure enough, Korean adults are better than English speakers at distinguishing tight fit from loose fit.

Boroditsky’s Web site is here.  If you’d like to learn more about linguistic relativity, this paper (PDF) might be a good starting point.

Reflections on the Implicit Association Test

July 8, 2009

NEWSWEEK’s Raina Kelley writes:

…I have spent the next 12 years leaving my purse wide open and at least six feet away from me. It’s my penance for having automatically assumed a black man in L.A. was a criminal. Being black doesn’t get me a pass on unconscious negative feelings about African-Americans or the shame we feel when they become conscious. We see the same cultural indicators as everybody else—back then, hours of riot footage, rap videos, and the O.J. trial had created an automatic connection in my mind between African-American Los Angelenos and danger.

So, I was actually excited to read about a new study published in the Journal of Personality and Social Psychology in which researchers from the University of Washington confirmed the validity of the Implicit Association Test (IAT). The IAT made a lot of news late last year when results showed that 70 percent of those who took it harbor an unconscious preference for white people over black people. And no, I’m not talking about 70 percent of white people—I mean people of all races who took it, including African-Americans.

The Implicit Association Test can be accessed here.

Right ear more responsive to requests than left ear, study finds

June 27, 2009

Wired reports:

You’re in a loud and sweaty Italian dance club when a woman approaches you. To be heard over the techno, she leans in close and yells into your ear, “Hai una sigaretta?”

If she spoke into your right ear, you would be twice as likely to give her a cigarette than if she asked by your left ear, according to a new study that employed this methodology in the clubs of Pescara, Italy. Of 88 clubbers who were approached on the right, 34 let the researcher bum a smoke, compared with 17 of 88 whom she approached on the left.

“The present work is one of the few studies demonstrating the natural expression of hemispheric asymmetries, showing their effect in everyday human behavior,” write psychologists Daniele Marzoli and Luca Tommasi of the University G. d’Annunzio in Italy in the journal Naturwissenschaften.

It’s the latest in a series of studies that show that sound from both human ears is processed differently within the brain. Researchers have noted that humans tend to have a preference for listening to verbal input with their right ears and that given stimulus in both ears, they’ll privilege the syllables that went into the right ear. Brain scientists hypothesize that the right ear auditory stream receives precedence in the left hemisphere of the brain, where the bulk of linguistic processing is carried out.

The influence of ’stereotype threat’ on cognition

June 22, 2009

TIME Magazine reports:

As explicit discrimination has receded in the last two decades, culminating in the elevation of an African-American to the Presidency, a woman to the House Speakership and a black woman to the galactic dominance known as being Oprah Winfrey, those who study the effects of racism and sexism have had to cope with a difficult question: If discrimination is less powerful, why do some groups in society continue to fare worse than others? Has bias merely become better hidden, or are there other forces at work?
One theory that has gained influence among sociologists is that some members of stigmatized groups, when faced with stressful situations, expect themselves to do worse — a prophecy that fulfills itself. These expectations, which can occur even in otherwise fair (or fair-seeming) situations — such as, say, a standardized test — produce stress and threaten cognitive function. The effect is called “stereotype threat,” and African-Americans, girls, even jocks have all been shown susceptible to stereotype threat.

As explicit discrimination has receded in the last two decades, culminating in the elevation of an African-American to the Presidency, a woman to the House Speakership and a black woman to the galactic dominance known as being Oprah Winfrey, those who study the effects of racism and sexism have had to cope with a difficult question: If discrimination is less powerful, why do some groups in society continue to fare worse than others? Has bias merely become better hidden, or are there other forces at work?

One theory that has gained influence among sociologists is that some members of stigmatized groups, when faced with stressful situations, expect themselves to do worse — a prophecy that fulfills itself. These expectations, which can occur even in otherwise fair (or fair-seeming) situations — such as, say, a standardized test — produce stress and threaten cognitive function. The effect is called “stereotype threat,” and African-Americans, girls, even jocks have all been shown susceptible to stereotype threat.

Brain perceives happiness more quickly than it perceives fear, study finds

June 21, 2009

Science Daily reports:

…An international group of experts has carried out an in-depth study into how we process emotional expressions, looking at the pattern of cerebral asymmetry in the perception of positive and negative facial signals…

The results, published in the latest issue of the journal Laterality, show that the right hemisphere performs better in processing emotions. “However, this advantage appears to be more evident when it comes to processing happy and surprised faces than sad or frightened ones”, [study co-author J. Antonio Aznar-Casanova] points out.

“Positive expressions, or expressions of approach, are perceived more quickly and more precisely than negative, or withdrawal, ones. So happiness and surprise are processed faster than sadness and fear”, explains Aznar-Casanova.

This research study adds to previous ones, which had revealed asymmetries in the way the brain processes emotions, and enriches the international debate in cognitive-emotional neuroscience in terms of how to define the exact way in which human beings process these facial expressions.

Does brain chemistry underlie religious experience?

May 19, 2009

NPR reports:

…Some researchers are using new technologies to try to understand spiritual experience. They’re peering into our brains and studying our bodies to look for circumstantial evidence of a spiritual world. The search is in its infancy, and scientists doubt they will ever be able to prove — or disprove — the existence of God.

Does the ‘denomination effect’ explain our spending patterns?

May 13, 2009

NPR reports:

economists have researched the phenomenon, which they call the Denomination Effect. Priya Raghubir and Joydeep Srivastava did a series of experiments in the U.S. and China that showed people were much more willing to spend the same sum of money if they had smaller denominations instead of one large bill.
“We’ve done some studies with four quarters and a dollar, and we found that people were much less likely to spend the $1 note that they were given than the four quarters they were given,” Raghubir says.

(…) Economists have researched… the Denomination Effect. Priya Raghubir and Joydeep Srivastava did a series of experiments in the U.S. and China that showed people were much more willing to spend the same sum of money if they had smaller denominations instead of one large bill.

“We’ve done some studies with four quarters and a dollar, and we found that people were much less likely to spend the $1 note that they were given than the four quarters they were given,” Raghubir says.