Although several studies have shown left–right hippocampus asymmetry during learning, it is unclear whether such asymmetry also exists for the parahippocampal cortex, a structure within the limbic system that is also involved in memory and learning. Using a common mental navigation task known to activate the bilateral parahippocampal cortex, this study aimed at determining how BOLD activation in these two areas changes after 1 year of medical school, a program characterized by intensive verbal learning. Fifteen first-year medical students participated in this study and underwent two sessions of functional MRI, at a 1-year interval. In the first session, we observed marginal differences between left and right parahippocampal cortex activity. However, 1 year later, left parahippocampal activation significantly increased (+4.7%), whereas the right remained stable. These results bring new information as to how intensive learning can modify regional metabolism in the human brain and how the left parahippocampal region is particularly important for cumulative verbal memory.
aClinical Research Center
Departments of bDiagnostic Radiology
cNuclear Medicine and Radiobiology, Sherbrooke University Hospital Center (CHUS), Sherbrooke
dDepartment of Psychology, Quebec University of Trois-Rivières (UQTR), Trois-Rivières, Quebec, Canada
ePHELMA Grenoble National Polytechnique Institute (INP), Grenoble, France
* Michaël Bernier and Claudie Gauvreau contributed equally to the writing of this article.
Correspondence to Kevin Whittingstall, PhD, Department of Diagnostic Radiology, Faculty of Medicine and Health Science, Sherbrooke University Hospital Center, 3001, 12 North Avenue, Sherbrooke, QC, Canada J1H 5N4 Tel: +1 819 821 8000 74647; fax: +1 819 564 5442; e-mail: email@example.com
Received September 21, 2015
Accepted October 19, 2015