Week One . . . First Days in the Lab

My first week has been awesome. As a part of the SFS program, I am able to live and take a course at Harvard Summer School while working at my internship in the Psychiatry Neuroimaging Lab of Brigham and Women’s Hospital. I’ve settled into Harvard and my course, I’m getting along well with all my roommates, and I’ve started working at the lab. I spent the weekend settling into my room in Hurlbut (a dorm at Harvard). I’m in a double that’s part of a fourth-floor suite with six people and a bathroom.

I got started at my internship on Wednesday. In the morning, I went to a routine orientation for all Brigham and Women’s Hospital volunteers. That afternoon I went over to the lab, where I was paired with a full-time research assistant, Kate. I took some quick online training courses, and then Kate set me up with an account and taught me the basics of how things work on their computer system. She also taught me how to use Slicer, a computer program that allows the user to view and edit 3-D brain scans by working with roughly 100 slices of the brain from all three directions (front, top, and side).

On Thursday I actually got to start working. I learned two processes: masking and realignment. In masking, I basically create a volumetric measure of the grey matter, white matter, and CSF (Cerebral Spinal Fluid, or fluid that the brain sits in). To do this I use Slicer to put a blue “mask” over the desired parts, leaving the unwanted parts of the brain scans aside. These masks are then used in studies to compare different volumetric ratios between different people’s brains.

Thursday afternoon, I learned realignment. In order to properly compare different brain scans, the lab must have them all facing the same exact way. However, the lab receives brain scans from multiple hospitals, and occasionally people will hold their head slightly sideways while being scanned. This is where realignment comes in. To realign a brain scan, I locate key structural points in the brain and place a point on them. Using these points, Slicer realigns the brain scan so that it is not tilted, leaning, or twisted in any way. Once each brain scan is realigned, comparisons go much more smoothly.

On Friday I began a reliability test for Kate. She is currently on a project that is exploring the correlation between the cognitive issues involved with schizophrenia and cortical folding in the left and right anterior cingulate cortex. In simpler terms, the general population tends to have a more prominent sulcus (or groove) in a specific area of the left hemisphere of their brain than they do in the same area of the right hemisphere of their brain. This is referred to as left asymmetry, because the left side has a greater groove. In schizophrenic patients, however, this does not appear to be true. Rather, it appears that schizophrenics have either right asymmetry or equal left-right symmetry.

While this is an interesting lead, more data still needs to be collected. Collecting the data can be difficult, however, because the “prominence of a sulcus” tends to be a rather subjective judgment. In order to verify the data that Kate collected, I am performing a reliability test. This means that I go through the same 60 cases that she went through, classifying each sulcus as prominent, present, or absent based on length and continuity. If my results closely resemble hers, the study is more “reliable” because two independent researchers came up with the same results. On Friday, I completed the first 10 cases of 60.

Next week, I will continue this reliability test and I might also be assigned to a longer-term project.