Quantcast

functional magnetic resonance imaging

Brain images reveal effects of antidepressants

The experiences of millions of people have proved that antidepressants work, but only with the advent of sophisticated imaging technology have scientists begun to learn exactly how the medications affect brain structures and circuits to bring relief from depression. Researchers at the University of Wisconsin-Madison and UW Medical School recently added important new information to the growing body of knowledge. For the first time, they used functional magnetic resonance imaging (fMRI)–technology that provides a view of the brain as it is working–to see what changes occur over time during antidepressant treatment while patients experience negative and positive emotions.

Advanced Imaging Shows Crescendo, Diminuendo of Brain Circuitry

Using newly developed imaging techniques, neuroscientists for the first time have “unfolded” the brain’s sea-horse-shaped hippocampus to reveal how dynamic activity within the brain structure’s complex architecture orchestrates memory formation. Details appear in the Jan. 24 edition of the peer-reviewed journal Science. The researchers used extremely high-resolution functional magnetic resonance imaging (fMRI) and software developed at UCLA’s Ahmanson-Lovelace Brain Mapping Center to study blood flow within the hippocampus as 10 human volunteers learned to associate names with faces.

Scientists ID brain regions where nicotine affects attention, cognitive skills

Nicotine administration in humans is known to sharpen attention and to slightly enhance memory. Now scientists, using functional magnetic resonance imaging (MRI), have identified those areas of the brain where nicotine exerts its effects on cognitive skills. Their findings suggest that nicotine improves attention in smokers by enhancing activation in the posterior cortical and subcortical regions of the brain–areas traditionally associated with visual attention, arousal, and motor activation. This study provides the first evidence that nicotine-induced enhancement of parietal cortex activation is associated with improved attention.

The Brain Gets the Big Picture

When you look at a picture, your brain has to put together lines, patterns and shapes to make a meaningful scene. New research by neuroscientists at the University of California, Davis and the University of Minnesota shows that higher regions of the brain can quickly recognize patterns and shapes and tell lower areas of the brain to stop processing the information. The finding confirms predictions from computer models and helps explain how the human brain makes sense of what the eyes see.

Monkey see: MRI technique finds big differences in human, primate sight

Don't look at me, I'm hideous.Researchers in Ohio say they’ve developed a way to use a decade-old imaging technology to directly compare the brains of monkeys and humans. Specifically, they used MRIs to compare parts of the monkey and human brains — the visual cortex — concerned with processing visual information. “Implicit in the neuroscience community was that the monkey cortex is a good model for the human cortex,” said one of the researchers. “Scientists didn’t have any choice but to make that assumption, as the monkey brain was the only model we had to work with.” But with the MRI they’ve found that there are in fact big differences.