DOBSON — Surry Community College psychology instructor, Wally Prichard, was a co-writer of an article titled, “Functional Brain Networks Formed Using Cross-Sample Entropy Are Scale Free” that recently ran in the neuroscience journal, Brain Connectivity. Other contributing writers were Paul J. Laurienti, Jonathan H. Burdette, and Satoru Hayasaka, who are instructors at Wake Forest School of Medicine.
Network theory is a branch of mathematics that has in recent years been applied to data from a wide variety of scientific disciplines. The recent article co-authored by Pritchard applied network theory to the imaging of activity levels in different parts of the brain using a method called functional magnetic resonance imaging or fMRI.
Traditional fMRI looks for “hot spots” of activity in various parts of the brain that may be related to many different things such as mental illness or cognitive processes. Traditional fMRI does not provide information regarding how different parts of the brain ‘talk to’ or interact with each other. Network theory enables that sort of question to be answered.
Pritchard’s study formed networks based on a measure that reflects nonlinear relations between different brain areas called cross-sample entropy, which was unlike previous studies that have considered different areas of the brain to be linked if the Pearson correlation coefficient between the data from each exceeded some threshold value.
“This theory would raise the question for future research on how these modes might change depending on what specifically the brain is processing at the moment. The data we analyzed were from participants who were not doing a specific task. The communication modes could also be different when a person has some type of brain abnormality or mental illness,” Pritchard said. “Using the nonlinear measure resulted in brain networks that had fundamentally different properties than networks formed using the traditional linear measure. In particular, the nonlinear networks featured so-called hubs — parts of the brain in communication with many other parts — something not seen in linear brain networks.”
Psychology classes are offered at Surry Community College as part of the College Transfer program that allows students to complete two years of study at the community college level before transferring to a four-year college or university. For more information, go to www.surry.edu.