Sean Wo: Filling in the Gaps BACK

Published by AFAR

This is Sean Wo's second entry. Read his first MSTAR Diary to learn how he began his MSTAR experience.

This Tuesday was a particularly long one because of the weekly noontime meeting. Every week, I meet with a group of other students doing summer research in geriatrics or gerontology. This gives us an opportunity to present our work and receive feedback on our project designs as well as presentation skills that’ll be useful at a poster conference. Each of these sessions is hosted by Drs. Stephanie Studenski and CF Reynolds III, esteemed geriatricians at Pitt Med.

Before this meeting, however, I worked on getting an automated brain stripping technique to work. In addition to measuring brain cortical thickness, I’m also working on getting the volumes of various brain regions measured automatically. The trickiest part of this process has turned out to be finding a way to select the parts of an MRI that contain only brain parenchyma and nothing else. Now, this is a long and tedious job for a human to do, but a computer can do a reasonable job in a few minutes. That is, if I can find the right algorithms to do so. After much trial and error, I found a way that stripped skulls from 61 of my 62 brains well, but failed badly on one, leaving behind the entire left eye and a large chunk of occipital bone. It took more than 3 hours of computation time, but I’d say 61 out of 62 half-decent strips ain’t bad at all. Suffice it to say that no paper written on the subject of automated skull stripping concludes that it’s a solved problem.

As ever, the projects presented today at the noontime meeting were very interesting. The first dealt with the neurotoxic side effects of adjuvant chemotherapy on balance, while the second aimed to explore psychiatric predictors of lower back surgery outcomes. Both had samples drawn from older populations, and both were in their early stages. Nevertheless, both addressed fascinating research questions very relevant to current clinical practice.

After this hour-long meeting, however, was a much longer one dealing with using statistical software. Two professional statisticians gave us a crash course on all of statistics, covering everything from types of variables to types of regression. Fortunately, I have some background in using the more common statistical tools. After that, they showed us how to use SPSS to test various hypotheses on a sample data set. I can’t say I got much out of the 2 and a half hour ordeal, but I did learn how to quickly inspect my data for normality using a P-P plot.

I spent the rest of the day reading up on reviews of brain aging. I was hoping I could find one big, up-to-date review that would summarize everything worth knowing about the aging brain, but alas, no such perfect review exists. I can’t complain. Science is democratic in that the people complaining about gaps in the literature ought to consider filling in those gaps themselves.

 

 

"Diary of an MSTAR Student" follows scholars in the 2011 Medical Student Training in Aging Research (MSTAR) Program, highlighting their summer experiences. As they continue their path of research, training and clinical practice, read their daily thoughts at www.afar.org/mstarblog. New diary entries are posted every day, so check back soon.