Gender differences in navigation performance are associated with differential theta and high-gamma activities in the hippocampus and parahippocampus.

Hippocampal rhythms are important for spatial navigation. This study examined whether gender differences in human navigation performance are associated with differences in hippocampal rhythms. We measured brain activities in males and females with whole-head magnetoencephalography (MEG), while they performed a virtual Morris water maze task. Behavioural results showed clear gender differences: males were significantly faster than females; unlike males, females did not show improved navigation performance in a familiar vs. new environment. MEG results showed that the magnitudes of right hippocampal/parahippocampal theta rhythm were similar between the two groups during navigation in a new environment; however, unlike males who exhibited a significant decrease in right hippocampal/parahippocampal theta power in the familiar environment shown before, females showed no change. This result may suggest faster environmental learning in males vs. females. After navigating in the new environment during the inter-trial (ITI) rest periods, males showed significantly higher right hippocampal/parahippocampal high-gamma power than females, suggesting greater consolidation in males. Moreover, right hippocampal/parahippocampal theta power during navigation correlated with navigation performance in both genders; high-gamma power during the ITI was correlated with navigation performance only in males. These associations may provide further support for the functional importance of theta and high-gamma rhythms in navigation. Overall, this study provides new insights into the neurophysiological mechanisms underlying gender differences in spatial navigation.