Healthy young adults use different strategies when navigating in a virtual maze. Spatial strategies involve using environmental landmarks while response strategies involve executing a series of movements from specific stimuli. Neuroimaging studies previously confirmed that people who use spatial strategies show increased activity and gray matter in the hippocampus, while those who use response strategies show increased activity and gray matter in caudate nucleus (Iaria et al., 2003; Bohbot et al., 2007). A growing number of studies report that cognitive decline that occurs with normal aging is correlated with a decrease in volume of the hippocampus. Here, we used voxel-based morphometry (VBM) to examine whether spatial strategies in aging are correlated with greater gray matter in the hippocampus, as found in our previous study with healthy young participants. Forty-five healthy older adults were tested on a virtual navigation task that allows spatial and response strategies. All participants learn the task to criterion after which a special “probe” trial that assesses spatial and response strategies is given. Results show that spontaneous spatial memory strategies, and not performance on the navigation task, positively correlate with gray matter in the hippocampus. Since numerous studies have shown that a decrease in the volume of the hippocampus correlates with cognitive deficits during normal aging and increases the risks of ensuing dementia, the current results suggest that older people who use their spatial memory strategies in their everyday lives may have increased gray matter in the hippocampus and enhance their probability of healthy and successful aging.
Keywords: aging, radial maze, spatial memory, hippocampus, navigation
Citation: Konishi K and Bohbot VD (2013) Spatial navigational strategies correlate with gray matter in the hippocampus of healthy older adults tested in a virtual maze. Front. Ag. Neurosci. 5:1. doi: 10.3389/fnagi.2013.00001
Received: 01 May 2012; Accepted: 07 January 2013;
Published online: 20 February 2013.
Edited by:Thomas Wolbers, German Center for Neurodegenerative Diseases, Germany
Reviewed by:Diego Ruano, University of Sevilla, Spain
Copyright © 2013 Konishi and Bohbot. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
*Correspondence: Véronique D. Bohbot, Department of Psychiatry, Faculty of Medicine, McGill University, Douglas Mental Health University Institute, FBC Building, 6875 boul. LaSalle, Verdun, QC H4H 1R3, Canada. e-mail: email@example.com