Authors: David Howett, University of Cambridge, UK
Researchers at Colombia University, New York (NY, USA), have recently demonstrated that tau pathology induces dysfunction in cells specifically tuned to compute spatial information. The research – published recently in Neuron – demonstrates a pathological interaction between tau and grid cells (GCs) in the entorhinal cortex (EC) that culminates in spatial memory deficits reminiscent of early Alzheimer’s disease (AD).
Early AD is characterized by the accumulation and aggregation of hyperphosphorylated tau in the EC, the primary site of neurodegeneration in AD . Subsequently, tau spreads in a transynaptic fashion to the hippocampus and the wider neocortex .
The EC has a pivotal role in computing components of spatial cognition, including current location, as evidenced by density of specialized spatially tuned cells. In fact, layer II of the medial EC (mEC) has the highest density of cells that periodically fire in a uniform hexagonal grid when animals explore an environment, hence the name: grid cell (figure 1) . The discovery of GCs in the mEC was worth one half of the Nobel Prize in 2014 .