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Mother's milk is OK, even for the in-between babies

“Stop feeding him milk right away – just to be safe” was not what a new mother wanted to hear. The call came several days after Tamara Caspary gave birth to fraternal twins, a boy and a girl. She and husband David Katz were in the period of wonder and panic, both recovering and figuring out how to care for them. “A nurse called to ask how my son was doing,” says Caspary, a developmental Read more

Focus on mitochondria in schizophrenia research

Despite advances in genomics in recent years, schizophrenia remains one of the most complex challenges of both genetics and neuroscience. The chromosomal abnormality 22q11 deletion syndrome, also known as DiGeorge syndrome, offers a way in, since it is one of the strongest genetic risk factors for schizophrenia. Out of dozens of genes within the 22q11 deletion, several encode proteins found in mitochondria. A team of Emory scientists, led by cell biologist Victor Faundez, recently analyzed Read more

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Dynamic functional connectivity

How can neuroscientists tell that distant parts of the brain are talking to each other?

They can look for a physical connection, like neurons that carry signals between the two. They could probe the brain with electricity. However, to keep the brain intact and examine cheap oakley function in a living person or animal, a less invasive approach may be in order.

Looking for functional connectivity has grown in popularity in recent years. This is a way of analyzing fMRI (functional magnetic resonance imaging) scans, which measure activity in the brain by looking at changes in blood oxygen. If two regions of the brain “light up” at the same time, and do so in a consistent enough pattern, that indicates that those two regions are connected.*

Functional connectivity networks

Shella Keilholz and her colleagues have been looking at functional connectivity data very closely, and how the apparent connections fluctuate over short time periods. This newer form of analysis is called “dynamic” or “time-varying” functional connectivity. Functional connectivity analyses can be performed while the person or animal in the scanner is at rest, not doing anything complicated.

“Even if you’re lying in the scanner daydreaming, your mind is jumping around,” she says. “But the way neuroscientists usually average fMRI data over several minutes means losing lots of information.”

Keilholz is part of the Wallace H Coulter Department of Biomedical Engineering at Georgia Tech and Emory. She participated in a workshop at the most recent Human Brain Mapping meeting in Seattle devoted to the topic. She says neuroscientists have already started using dynamic functional connectivity to detect differences in the brain’s network properties in schizophrenia. However, some of that information may be noise. Skeptical tests have shown that head motion or breathing can push scientists into inferring connections that aren’t really there. For dynamic analysis especially, preprocessing can lead to apparent correlations between two randomly matched signals.

“I got into this field as a skeptic,” she says. “Several years ago, I didn’t believe functional connectivity really reflects coordinated brain activity.”

Now Keilholz and her colleagues have shown for the first time that dynamic functional connectivity data is “grounded”, because it is linked with changes in electrical signals within the brain. The results were published in July in the journal NeuroImage. The first author is graduate student Garth Thompson. Read more

Posted on by Quinn Eastman in Neuro Leave a comment