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Young healthy participants spontaneously use different strategies in a virtual radial maze, an adaptation of a task typically used with rodents. We have previously shown using fMRI that people who use spatial memory strategies have increased activity in the hippocampus whereas response strategies are associated with activity in the caudate nucleus. In addition, we used Voxel Based Morphometry (VBM) to identify brain regions co-varying with the navigational strategies individuals used. Results showed that spatial learners have significantly more grey matter in the hippocampus and less grey matter in the caudate nucleus than response learners. The relationship between spatial memory strategies and grey matter of the hippocampus was replicated with healthy older adults. Furthermore, we found a positive correlation between spatial memory strategies and the MoCA, which is a test sensitive to mild cognitive impairment. Since low grey matter in the hippocampus is a risk factor for cognitive deficits in normal aging and for Alzheimer’s disease, our results suggest that using spatial memory in our everyday lives may protect against degeneration of the hippocampus and associated cognitive deficits These results have important implications for intervention programs aimed at healthy and successful aging.

The basic understanding of the physical mechanisms in material science can emerge from careful measurements where one physical parameter is varied at a time. Here we present muon-spin rotation measurements on polycrystalline samples of the antiferromagnetic zigzag chain families Na_{x}Ca_{1-x}V_{2}O_{4} and Eu$L_2$O_4. We find a diverse magnetic ground state in these families, and show that by slightly changing the electronic or magnetic properties we end up with a different magnetic ground state.