How do ramping dynamics influence computations in the entorhinal cortex?

The entorhinal cortex is crucial for declarative memory and spatial cognition. Recent experiments reveal that many entorhinal neurons represent information through ramping activity in which their firing rate changes monotonically between behaviourally relevant boundaries. This Opinion considers the implications of entorhinal ramping dynamics for computations within the hippocampal formation. Localised firing of extensively investigated grid, border, and object cells is suited to categorisation and rapid learning, whereas ramping activity may reflect compressed codes for communication between areas, or entorhinal computations suited to generalisation. Thus, ramping dynamics may be a manifestation of fundamental but largely overlooked mechanisms contributing to memory and spatial cognition, suggesting a need to re-evaluate models of hippocampal-entorhinal function centred exclusively on sparse, localised codes.