Exploring anterograde associative memory in London taxi drivers

Abstract

London taxi drivers are renowned for their navigation ability, spending a number of years acquiring 'The Knowledge' of London's complex layout and having to pass stringent examinations to obtain an operating licence. In several studies, this navigation skill has been associated with increased posterior but also decreased anterior hippocampal grey matter volume. Neuropsychologically, gain and loss has also been documented in taxi drivers; while very skilled at navigation in London, they are significantly poorer than controls at learning and recalling new object-location associations. Here we tested a group of London taxi drivers and matched control participants on this object-location associations task, while also subjecting them to a battery of challenging anterograde associative memory tests involving verbal, visual and auditory material both within and across modalities. Our aim was to assess whether their difficulty in previous studies reflected a general problem with associative memory, or was restricted to the spatial domain. We replicated previous findings of poor learning and memory of object-location associations. By contrast, their performance on the other anterograde associative memory tasks was comparable with controls. This resolves an outstanding question in the memory profile of London taxi drivers following hippocampal plasticity, and underlines the close relationship between space and the hippocampus.

A Role for the Longitudinal Axis of the Hippocampus in Multiscale Representations of Large and Complex Spatial Environments and Mnemonic Hierarchies

“…While the PHC was activated during the traversal of all three mazes, the AHC was only involved when navigating through the largest and most intricate maze. A number of seminal human fMRI studies have measured hippocampal activation in licensed London taxi drivers, who are required to train over 4 years to learn the complex layout of London's streets [112][113][114][115]. Interestingly, these drivers had greater gray matter volume in PHC and less in AHC compared to matched controls [112,113].…”

“…However, they were significantly worse at forming and retaining new associations involving visuo-spatial information, suggesting that these may involve the AHC [113,114]. A follow-up study demonstrated that the taxi driver's ability to form associations between visual stimuli was intact, the impairment being specific to acquiring new information containing a spatial component [115]. Another study has shown that both imagination and 1-week recall of scenes engage AHC, suggesting its role in scene construction [116].…”

Sustainable Digital Environments: What Major Challenges Is Humankind Facing?

“…For instance, the brains of London taxi drivers, who are required to have an exceptionally detailed, large-scale training of the cognitive map for licensing, develop a larger hippocampus [89,90]. This suggests that small children's encounters with complex 3D digital game worlds may certainly have the same intensity and ask for different sensomotoric skills than the games of children some decades ago.…”

A reliable and valid method for manual demarcation of hippocampal head, body, and tail

“…Some researchers suggest anterior regions have specialized emotional and reward motivation functions in memory (Bannerman et al, 2004;Fanselow and Dong, 2010;Murty et al, 2010;Strange et al, 2014), however others identify similar correlations with posterior regions (Shafer and Dolcos, 2012;Dolcos et al, 2013). A popular hypothesis has been that posterior regions have unique spatial memory and navigation functions (Ryan et al, 2010;Woollett and Maguire, 2012), yet there is an evidenced role for anterior regions in recognition of relative spatial landmarks (Ekstrom et al, 2011;Morgan et al, 2011). Still others posit that anterior-posterior function may be organized on a scale of detail and flexibility in mnemonic processing -posterior regions are linked to detailed representations whereas anterior regions represent a gist of an experience rather than its details (Poppenk et al, 2013).…”