Neural underpinnings of 3D cognitive mapping
Supervisors:
Prof Kate Jeffery, School of Psychology & Neuroscience
Prof Quintin Cutts, School of Computing Science
Summary:
The brain’s “cognitive map” of space, used for navigation and possibly reasoning, depends on a “cognitive compass” generated by head direction (HD) neurons. On flat terrain, HD cells generate a signal that remains aligned with the outside world so as to continuously signal facing direction.
However, the world is not flat. Many animals (including ourselves) regularly navigate 3D spaces, sometimes upside down. Surprisingly, HD cells are insensitive to forward-back head tilts, and when the head inverts the signal ceases altogether. The cognitive compass is thus not 3D. How might this alter cognitive mapping in inversion? In mice, we will record HD cells as the animals explore spheres or other 3D structures, to determine (a) how the cells handle inversion, when the compass signal must either flip (unlikely) or inactivate (more likely), and (b) whether the animals can navigate. These experiments will run parallel to psychological studies in humans, in which we create analogous virtual reality worlds and investigate cognitive mapping and higher order space-like reasoning in inversion. The neural results will inform modelling of the dynamical organisation of the HD system, deepening our understanding of the neural mechanisms of cognitive mapping and revealing potential limits these place on human reasoning.