I had the pleasure of writing a Preview for Neuron for a recent paper by Erie Boorman’s group. It’s out now!
The paper led by Seongmin Park was published online in Neuron a few weeks ago (find it here). By combining an intricate experimental design with fMRI, Park and colleagues show that the brain forms unified cognitive maps of relational knowledge. Participants learned the rank orders of two groups of individuals along two separate dimensions. Unbeknownst to participants, the individuals could be arranged in a two-dimensional space. Initially, participants learned about each group in isolation. Only on the third day of training, participants encountered so-called hub individuals, which linked the two groups. By relying on these hubs, participants could infer relationships between pairs of individuals that were made up from members of the different groups. Using fMRI repetition suppression analysis and multi-voxel pattern similarity analysis, Park et al. show that the hippocampal-entorhinal region and medial prefrontal cortices spontaneously combine the rank orders to two-dimensional cognitive maps. In my preview, I summarize the original study and discuss some of its implications.
If you are curious to find out more, you can find the PDF here.