Proceedings of the Annual Meeting of the Cognitive Science Society

Different memory systems, dependent on separate parts of the brain, can sustain successful navigation. The hippocampus is implicated in spatial memory strategies used when finding one’s way in the environment, i.e. it is allocentric and involves remembering the relationship between landmarks. On the other hand, another strategy dependent on the caudate nucleus can also be used, i.e. the response strategy, which relies on making a series of stimulus-response associations (e.g. right and left turns from given positions). Participants who use the response strategy are faster at learning navigation tasks lending themselves to using a single specified route. Young adult response learners have increased fMRI activity and grey matter in the caudate nucleus, but decreased fMRI activity and grey matter in the hippocampus. Research in my laboratory has shown that specific navigation strategies are associated with several genes, such as BDNF and ApoE, as well as hormones, such as cortisol and progesterone, but not estrogen and progesterone. Experiences dependent modulators such as age, habit, stress and rewards also modulate strategies dependent on the hippocampus and caudate nucleus. These results have important translational implications because a larger hippocampus has been associated with healthy cognition in normal aging and with a reduced risk of numerous neurological and psychiatric disorders such as Alzheimer’s disease, Schizophrenia, Post-Traumatic Stress disorder and Depression.