Graduate Student Seminar for April 16

Joseph Holtrop (Bioimaging), Brendon Smith (Bioacoustics), and Brennan Payne (Human Perception and Performance) will present on April 16 at noon in Beckman room 1005 as part of the Graduate Student Seminars. Lunch will be served.

Joseph Holtrop

Toward High Resolution Diffusion Weighted Imaging
Diffusion weighted imaging (DWI) in magnetic resonance imaging (MRI) is a technique that looks at restrictions to the diffusion water. By looking at the restrictions to diffusion in many directions, measures of tissue microstructure can be obtained. These microstructural measures have made diffusion imaging a popular technique for assessing the structure integrity of white matter pathways in the brain in vivo. However, due to several challenges, diffusion weighted imaging has been limited to fairly low resolutions compared to other structural imaging techniques in MRI. We have been developing a data acquisition strategy that uses a 3D multi-slab approach to overcome the challenges of traditional techniques for DWI that has limited it to low resolutions. Through the use of an SNR efficient data acquisition strategy we have been able to achieve spatial resolutions comparable to other high resolution structural imaging methods with MRI. By improving the resolution and SNR of DWI, better measures of tissue microstructure are able to be made along with enabling the investigation of small structures that were not distinguishable at lower resolutions.

Brendon Smith

Tomatoes and soy germ for reduction of atherosclerosis
Cardiovascular disease (CVD) claims nearly 800,000 lives per year in the United States, and remains the leading cause of death despite significant medical advances. A condition known as atherosclerosis drives the development of CVD. Atherosclerosis is a complex pathological process characterized by entrance of cholesterol-containing lipoprotein particles into the arterial wall, with subsequent inflammation and formation of lipid-rich plaques. Atherosclerosis progresses silently throughout life, manifesting itself during adulthood in heart attacks and strokes. Diet has been acknowledged as an important determinant of CVD risk. In epidemiological studies and clinical trials, adherence to a healthy diet rich in fruits, vegetables, nuts, and whole grains has been shown to reduce risk of CVD and reduce mortality if CVD is already present. Although the benefits of a generally healthy dietary pattern are clear, effective combinations of specific nutritional components remain to be identified. Data will be presented from an ongoing research project, funded in part by the Beckman Graduate Fellowship, evaluating the cardiovascular benefits of tomato and soy germ. This work will have public health relevance by demonstrating a specific combination of nutritional components that can reduce risk of heart attacks, strokes, and other types of adverse cardiovascular events.

Brennan Payne

Characterizing the cognitive aging of working memory and language comprehension: Mechanisms and compensatory factors
Maintaining effective language understanding and communication into old age is crucial not only for learning new information in adulthood, but also for continued cognitive resilience. At the same time, age-related declines in core cognitive abilities such as working memory have a profound effect on certain aspects of language comprehension. This is especially troubling because formal educational opportunities are front-loaded to early in life, so that reading is one of the major conduits through which older adults learn new information and seek mental stimulation. In this talk, I will present recent research from our lab indicating potential mechanisms underlying the influence of age-related declines in verbal working memory on language processing in normal aging. Finally, I discuss several factors that may ameliorate the influence of age-related declines in working memory on language understanding, including the compensatory influence of language experience and the potential for language comprehension to be improved through short-term computerized working memory training.