Sunday, February 8, 2009
Focus on Visual Processing Development in Three Ways
The UNM began a few weeks ago, and even with everything else that is going on, I am doing some interesting work. In particular, I am interested in how differences in development between what is called the dorsal visual stream (a.k.a. the where stream) and the ventral visual stream (the what stream) may be affected by autism, what symptoms may arise from that, and how such developmental differences may be similar to and different than those in people who are neurotypical visual learners. What I want to do with this information is called translational research--that part of research that focuses on using the basic science to development treatments and educational interventions to help people with ASD use their visual gifts and yet interact with the rest of the world.
My coursework this semester is quite specialized in order to help me delve more deeply into my interests.
The only organized course I have is Psychology 650: Introduction to Neuroimaging Analysis. In this course, we will learn how to interpret data provided by the various neuroimaging techniques: EEG, ERP (event-related potentials),MEG, Positron Emission Tomography (both PET and SPECT), fMRI (functional magnetic resonance imaging, and MRS (magnet resonance spectroscopy). Each technique has strengths and weaknesses, and each has specific ways to properly interpret the data collected from it. My purpose here is to be able to tell when conclusions made in the original research are warrented or not, and also learn how to analyze and interpret data that I get from my research.
In this class, the professor lectures about a technology--right now we are doing EEG and ERP--and then assigns us papers to critique. The doc students (like me) have the additional assignment of finding papers in their area of interest to critique. EEG and ERP are particular interests for me, because much of the data in my area of interest is gathered from these electrical imaging techniques. However, there is a very specialized vocabulary for interpretation, so that even though I know my neuroanatomy and neurophysiology, and even though I understand the physics of the EEG and ERP methods, I find myself getting lost on the interpretation. The prof did not assign a textbook, and it is hard to tell what sources on the web are reliable and relevant. So I e-mailed the prof and asked about a book. He recommended one, but naturally, our university library does not have it. However, Amazon does, and at a very reasonable price. So I am eagerly awaiting Steve Luck's An Introduction to the Event-related Potential Technique in Cognitive Neuroscience.
I am also taking hours for Psychology Problems 550 with my second major advisor, Dr. C. These problems involve the neurodevelopment in visual processing and also differences in cognitive switching, and will result in my name going on two published papers. I am currently finding and reading papers on the trajectory of cortical development as measured by the thickening and thinning of the cortex of the brain in normal children, intellectually gifted children, children with ADHD, children with autism spectrum disorders (ASD), and other developmental differences. Here is where the class on analysis is paying off already, even though my understanding is still at the novice level. Now when I read papers, I can at least begin to understand why two different papers using the same technique can come up with very different results. Much of that has to do with how differently they collected their data, and how they interpret it.
Finally, I am also taking Special Education 595: Indepedent Readings in Special Education with my first major advisor, Dr. N. I am meeting with her tomorrow in order to determine a direction for my readings. I am proposing to look into the connection between visual processing and deficits in working memory for people with ASD. This also involves the development and functioning of the two visual streams. I am hoping to agree upon writing a Literature Review on this, using information from cognitive testing to bridge the gap in understanding between the basic science and methods for helping with working memory.
Working memory is the cognitive ability to temporarily store and mentally manipulate limited amounts of information in order to guide behavior. (Behavior here can mean anything from mental math activities to choosing what to pay attention to and what to ignore). Auditory working memory is known to be deficient in ADHD, and certain forms of ASD. New evidence is now coming out that suggests a link between visual processing and attention, that seems to also affect visual working memory. And I have a great interest in this area, as I explained above.
What is really good about my coursework this semester is that each one contributes to and reenforces the others, and all of them allow me to focus on my particular area of interest. This is how a Ph.D. progresses. Coursework starts off broadly, working off the master's degree, but as the doc student progresses, it increasingly narrows towards the dissertation interests. All the papers read, all the knowledge gained during the coursework phase prepares the student for Comprehensive Exams. These are exams that test the student in the areas of interest important to the dissertation topic, and assure the candidate's committee that she is conversant in the narrow field. Once the comprehensive exams are completed, the student then begins the often lonely process of finishing the research and writing the dissertation. Good advisors try to help their students maintain a narrow focus in a particular area, so that the dissertation actually gets written before old age sets in! Once the dissertation is finished and successfully defended, the new Ph.D. has joined the community of scholars by virtue of expertise in a narrow area and by expertise in the research process. Then the new scholar can once again attend to broad areas of interest to the field.
I have very good advisors. Whenever I want to go off on a tangent, both of them sit me down and
force my attention strongly encourage me to get back on track.
I am going to be much closer to the dreaded Comps after this very focused semester!