Complex Navigation in Cities
I’ve blogged a few times about the London cabbies, and the potential to help people grow hippocampal neurons through use of simulated landmark navigation problems. The natural question for someone seeking to develop a therapeutic video game would be, “just what sort of map layout is best for neuronal activation?” This summary of recent research suggests some answers.
First, it is interesting to note that real cities are more difficult than randomly-generated maps; apparently due to clustering or lack of homogeneity. Second, it is not surprising that grid layouts are less challenging. In places like Manhattan, or Kenosha, WI, it is easy to find places on novel routes without relying on landmarks or much of a sense of direction. The act of navigation is pure sequencing; caudate nucleus. On the other hand, older cities have circle and spoke layouts and other tricky features; and hilly areas like Seattle tend to “ease” off of ninety degrees and end or merge parallels in unexpected places. Such deviations from the 4 cardinal directions wreaks havoc on mental sequencing and forces you to switch back to landmarks and sense of direction; hippocampus.
Interestingly, one study used the number of network nodes to prove that older cities are more complex. However, I believe that the number of nodes is not the key factor — especially in grid versus old city design. On the one hand, inplaces with very dense grids and a number of missing nodes (dead ends, non-intersections, etc), it is not that difficult to navigate. Such navigation can be done as a sequence of steps filtered against a mental blacklist of known missing intersections. If you miss a turn, there are lots of alternative turns you can make up on the fly to get the same result. A map with fewer intersections but more curves and merges would be significantly harder for people to navigate, and would activate hippocampus much better.