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magnetic resonance imaging

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Researchers have found that brain scans show that skipping breakfast makes fatty, high calorie foods appear far more attractive later in the day.

Scans of 21 people showed the brain was more attracted to food if breakfast was missed and people had more food at lunch.

Scientists said it made loosing weight challenging as missing meals made calorific food even more appealing.

Nutrition experts say breakfast is known to take the edge off appetite.

However, researchers were curious about what happened inside the brain to alter the food people choose to eat.

Twenty one people, who were all normal weight, were shown pictures of calorie packed foods while they were positioned in a magnetic resonance imaging (MRI) machine at Imperial College London.

On one day they were given no breakfast before the scans and on a different day they were fed a large, 730 calorie, breakfast an hour and a half before.

The researchers said skipping breakfast created a “bias” in the brain in favor of high calorie foods.

The results, presented at the Neuroscience 2012 conference, showed the brain changed how it responded to pictures of high calorie foods, but not low calorie foods, when breakfast was skipped.

They showed part of the brain thought to be involved in “food appeal”, the orbitofrontal cortex, became more active on an empty stomach.

When the researchers offered the participants lunch at the end of the study, people ate a fifth more calories if breakfast was missed.

Dr. Tony Goldstone, from Imperial College London, said: “Through both the participants’ MRI results and observations of how much they ate at lunch, we found ample evidence that fasting made people hungrier, and increased the appeal of high calorie foods and the amount people ate.

“One reason it is so difficult to loose weight is because the appeal of high calorie food goes up.”

Future studies will investigate how obesity affects the same system in the brain.

 

Researchers say that interacting within a group, such as taking part in jury deliberations or mingling at a cocktail party, can lower your intelligence, with women being particularly susceptible.

Scientists at Virginia Tech Carilion Research Institute used magnetic resonance imaging (MRI) to investigate how the brain processes information about social status in small groups and how perceptions of that status affect expressions of cognitive capacity.

In other words, whether “feeling” less intelligent than others can affect your decision-making.

“You may joke about how committee meetings make you feel brain dead, but our findings suggest that they may make you act brain dead as well,” said Read Montague, director of the Human Neuroimaging Laboratory and the Computational Psychiatry Unit at the institute, who led the study.

 

Researchers say that interacting within a group, such as taking part in jury deliberations or mingling at a cocktail party, can lower your intelligence

Researchers say that interacting within a group, such as taking part in jury deliberations or mingling at a cocktail party, can lower your intelligence

 

Read Montague explained that when volunteers in a group were told how the others performed, it lowered their problem-solving abilities.

He said: “We started with individuals who were matched for their IQ.

“Yet when we placed them in small groups, ranked their performance on cognitive tasks against their peers, and broadcast those rankings to them, we saw dramatic drops in the ability of some study subjects to solve problems. The social feedback had a significant effect.”

What’s more, a pattern emerged along gender lines.

The women and men both had the same baseline IQ scores, but more women fell into the lower performing group.

Lead author Kenneth Kishida added: “Our study highlights the unexpected and dramatic consequences even subtle social signals in group settings may have on individual cognitive functioning.

“And, through neuroimaging, we were able to document the very strong neural responses that those social cues can elicit.”

Co-author Steven Quartz, a professor of philosophy in the Social Cognitive Neuroscience Laboratory of Caltech, said: “The idea of a division between social and cognitive processing in the brain is really pretty artificial. The two deeply interact with each other.”

The research appears in the January 23, 2012 issue of the journal Philosophical Transactions of the Royal Society B.