Understanding the aging brain Dr. Kristy Nielson, a professor of psychology, was one of the first in the nation to use functional MRI technology for aging research. She uses fMRI images to examine what parts of the brain function differently in older versus younger people or people at high versus low risk for disorders like Alzheimer’s disease. “Imaging is starting to allow us to see differences or changes before we can measure them with traditional tests, so it has both the potential to help us better understand the mechanisms of aging or neurodegenerative diseases and the potential to help us predict impairments before they occur so that we might be able to prevent them,” says Nielson, who is also the editor-in-chief of the journal Ageing Research. The image above depicts areas of the brain active during a semantic memory task (identifying if a name is famous or not) and an episodic memory task (knowing whether a name was read earlier or not). The images show snapshots of the brain from its base on the left to its top on the right. People who showed less brain activity during the semantic task and who had the gene APOE-E4, which is linked to Alzheimer’s, were more likely to experience cognitive decline just 18 months later. “Research in Alzheimer’s is usually focused on episodic memory — that is, what patients have the most difficulty with is remembering what they did last week, yesterday or earlier today,” Nielson says. “Although factual memory get less attention, how the brain does this simple

Dr. Kristy Nielson

task is very telling about who is likely to experience Alzheimer’s-like cognitive decline later on.”

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Building better nanodevices

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These images show a grown nanostructure created by Dr. Chung Hoon Lee, assistant professor of electrical and computer engineering and director of Marquette’s Nanoscale Devices Laboratory. The images were published in the journal Applied

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Physics Letters in November. Lee uses a high-powered microscope to learn about the

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nanostructure growth mechanism, and in 2012 he succeeded in growing atomically

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sharp tips at nanoscale, which could be used in materials such as metals, metal-oxides and polymers. “The applications of this technology are broad in science and engineering,” Lee says. One possible application: using a single molecule as an electric device such as an electronic computer chip, which may be more

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efficient than current computer chips, he says. Working within spaces less than 1/10,000th diameter of a human

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hair, Lee builds his nanostructures with an unusual method, using an optical lithography that is common in industry and an electrical field.

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4

Discover

Dr. Chung Hoon Lee