Maladaptive bias for extrahippocampal navigation strategies in aging humans
This source preferred by Jan Wiener
Authors: Wiener, J., de Condappa, O., Harris, M.A. and Wolbers, T.
Journal: The Journal of Neuroscience
Efficient spatial navigation not only requires accurate spatial knowledge but also the selection of appropriate strategies. Using a novel paradigm that allowed us to distinguish between beacon, associative cue, and place strategies, we investigated the effects of cognitive aging on the selection and adoption of navigation strategies in humans. Participants were required to rejoin a previously learned route encountered from an unfamiliar direction. Successful performance required the use of an allocentric place strategy, which was increasingly observed in young participants over six experimental sessions. In contrast, older participants, who were able to recall the route when approaching intersections from the same direction as during encoding, failed to employ the correct place strategy when approaching intersections from novel directions. Instead, they continuously employed a beacon strategy and showed no evidence of changing their behavior across the six sessions. Given that this bias that was already apparent in the first experimental session, the inability to adopt the correct place strategy is not related to an inability to switch from a firmly established response strategy to an allocentric place strategy. Rather, and in line with earlier research, age-related deficits in allocentric processing result in shifts in preferred navigation strategies and an overall bias for response strategies. The specific preference for a beacon strategy is discussed in context of a possible dissociation between beacon-based and associative cue-based response learning in the striatum, with the latter being more sensitive to age-related changes.