Monthly Archives: June 2008

The impact of cell phone use on driving

As this LA Times article describes, there exists a growing body of research which indicates that, given the finite nature of human cognitive processing power, multi-tasking while driving – especially using a cell phone – contributes to an increased risk of motor vehicle accidents.  Nonetheless, some states, now including California, apparently seek to find a politically-acceptable happy medium by outlawing the use of cellular handsets but not the use of hand-free headsets and in-car speakerphone systems.

On Tuesday [July 1, 2008] California motorists — as well as those in Washington state, where a similar law was recently passed — will be prohibited from talking on hand-held cellular phones while driving. Most, however, will likely continue their wireless business using headsets, speakers or other hands-free devices.

Gov. Arnold Schwarzenegger says the new law will reduce accidents. “Getting people’s hands off their phones and onto their steering wheels will save lives and make California’s roads safer,” he said earlier this month.

That, however, is not what the research finds. Scientists say that when mixing cellphones and driving, the number of hands available for the tasks is not the limiting factor.

Instead, it’s a driver’s attention and processing capacity. These are often stretched beyond safe limits when someone juggles the complex tasks of negotiating traffic and conversing with another remotely.

“There are limits to how much we can multi-task, and that combination of cellphone and driving exceeds the limits,” says David Strayer, a University of Utah psychologist… 


Brain differences between homosexuals and heterosexuals?

The Washington Post reports on the continuing debate among brain researchers regarding alleged differences in brain structure that are a function of sexual orientation.

Is there such a thing as a “gay brain”? And, if so, are some people born with brains that make them more likely to be homosexual? Or do the brains of gay people develop differently in response to experiences?

Those are some of the thorny questions that have been raised by a provocative new study that found striking differences between the brains of homosexuals and heterosexuals in both men and women.

Some scientists say the new findings are part of an increasingly convincing body of evidence that suggests sexual orientation results from fundamental developmental differences that are probably caused by hormonal exposures in the womb.

“This research is pointing to basic differences in the brain between homosexual and heterosexual people that are likely there right from the beginning,” said Sandra F. Witelson, a professor of psychiatry and behavioral neurosciences at McMaster University in Ontario. “These could be reflecting some genetic or hormonal factors that predetermine your sexual orientation.”

Others, however, argue that such research is far from conclusive.

“I remain skeptical,” said William Byne, a professor of psychiatry at Mount Sinai School of Medicine in New York. “There’s been a history of jumping to conclusions and overinterpreting findings in this field.”

To paraphrase Glenn Reynolds:  “Indeed.”

Did the human brain evolve to seek out innovative experiences?

Science Daily reports here on research by British scientists which suggests that human beings are predisposed to seek out the new and the unfamiliar:

In an experiment carried out at the Wellcome Trust Centre for Neuroimaging at UCL (University College London), volunteers were shown a selection of images, which they had already been familiarised with. Each card had a unique probability of reward attached to it and over the course of the experiment, the volunteers would be able to work out which selection would provide the highest rewards. However, when unfamiliar images were introduced, the researchers found that volunteers were more likely to take a chance and select one of these options than continue with their familiar — and arguably safer — option.

Using fMRI scanners…  Dr Bianca Wittmann and colleagues showed that when the subjects selected an unfamiliar option, an area of the brain known as the ventral striatum lit up, indicating that it was more active. The ventral striatum is in one of the evolutionarily primitive regions of the brain, suggesting that the process can be advantageous and will be shared by many animals.

“Seeking new and unfamiliar experiences is a fundamental behavioural tendency in humans and animals,” says Dr Wittmann. “It makes sense to try new options as they may prove advantageous in the long run. For example, a monkey who chooses to deviate from its diet of bananas, even if this involves moving to an unfamiliar part of the forest and eating a new type of food, may find its diet enriched and more nutritious.”

Is neuromarketing coming to a retailer near you?

Thanks to Cog Sci Blog reader “LF” for making me aware of this interesting article in The Atlantic concerning a (possibly) emerging field called neuromarketing:

[The] field of neuromarketing [argues] that fMRI [functional magnetic resonance imaging – brain scanning] technology provides fail-safe insights into consumer behavior. Unlike traditional methods of measuring the effectiveness of advertisements, fMRI defeats the curse of standard market-testing: the bias in self-reporting. In other words, if the ventral striatum [region of the brain] lights up when I drink Pepsi, this means—according to FKF, at any rate—that I find Pepsi greatly pleasurable, even if I report no particular experience of pleasure in a taste test.

Although neuromarketing, like other kinds of ‘applied’ brain research, has a long way to go before it can produce truly compelling data, I was please to read that the article made note of some of the various limitations and validity issues inherent in fMRI.

Your polling place impacts your voting decisions

ABC News reports on new research which suggests that the place where one casts a vote plays a role in how one votes:

A new study suggests that where people vote may affect how they vote.

“Seemingly innocuous factors can influence behavior,” said Jonah Berger, assistant professor of marketing at the Wharton School of the University of Pennsylvania, and the study’s lead author. “There is a connection between location and the thing people are voting on.”

Berger examined results from the 2000 Arizona general election and found that, even after controlling for location and political preferences, people who voted in schools were 2 percent more likely to support raising the state sales tax to increase education spending.

Berger’s experimental data supported the results of the analysis. He found that, when people were exposed to images of schools, including lockers and classrooms, they were more likely to vote for a hypothetical tax to fund public schools, than people who were exposed to less evocative images, such as office buildings.


The authors’ own abstract of their study:

American voters are assigned to vote at a particular polling location (e.g., a church, school, etc.). We show these assigned polling locations can influence how people vote. Analysis of a recent general election demonstrates that people who were assigned to vote in schools were more likely to support a school funding initiative. This effect persisted even when controlling for voters’ political views, demographics, and unobservable characteristics of individuals living near schools. A follow-up experiment using random assignment suggests that priming underlies these effects, and that they can occur outside of conscious awareness. These findings underscore the subtle power of situational context to shape important real-world decisions.


This study has been published in the Proceedings of the National Academy of Sciences.

Fearful expression aids in threat perception

I’ve long been interested in the evolutionary roots of much human behavior that we often consder to be a function of culture or social environment…  This LA Times article describes the benefits on perception of expressing fear, which no doubt provided an evolutionary benefit to our ancestors.

The look of fear is unmistakable: wide eyes, raised brows, a dropped jaw. But is it more than a social signal?

In this week’s journal Nature Neuroscience, University of Toronto researchers reported that fearful expressions evolved to heighten the senses and improve detection of physical threats.

Scientists asked 20 college students to assume fearful and neutral faces and measured their field of vision each time.

Fearful expressions enlarged the vision field by 7.6% compared with a neutral expression, presumably making it easier to spot an attacker. Scientists also measured eye movements and found that increased scanning took place when students’ expressions mimicked fear.

“When you’re fearful, you need to gather as much information as possible,” said lead author Joshua M. Susskind, a graduate student in psychology.

Brain activation – a function of native language?

The AP (via the LA Times) reports on new research indicating that different languages create different patterns of brain activation, regardless of one’s fluency in a given language.

Before we utter a single word, experts can determine our mother tongue and our level of proficiency in other languages by analyzing brain activity as we read, scientists working with Italy’s National Research Council say.

For more than a year, a team of scientists experimented on 15 interpreters, revealing what they say were surprising differences in brain activity when the subjects were shown words in their native language and in other languages they spoke.

The findings show how differently the brain absorbs and recalls languages learned in early childhood and those learned later in life, said Alice Mado Proverbio, a professor of cognitive electrophysiology at the University of Milano-Bicocca in Milan.

Proverbio, who led the study, said such research could help doctors communicate with patients suffering from amnesia or diseases that impair speech. It also could be of use someday in questioning refugee applicants or terrorism suspects to determine their nationality, she said.