Molecular and circuit mechanisms underlying paraventricular thalamic regulation of habituation to repeated stress

摘要

Reconciling grid cells with place cells over a set of flexible charts Alessandro Treves !-*, Chol Jun Kang, Davide Spalla', Federico Stella*>, Remi Monasson4 1 SISSA, Trieste, Italy 2 Kim II Sung University, Pyongyang, Republic of Korea 3 IST Austria, Klosterneuburg, Austria 4 ENS, Paris, France Grid cells have been regarded as a rigid system, essentially memory-less and almost frozen (Fyhn et al., 2007), at least after their developmental maturation. Recent data indicates, however, that such rigidity may be an artifact of studying grid cells in the lab, typically in a flat arena. If they have to represent spatial posi- tion ‘in the wild’, eg in the curved burrows where rats live, they need to express memory of several familiar locations. We have now shown that a grid network has a significant memory capac- ity for uncorrelated representations (Spalla et al., 2019), bringing grid cells closer to place cells; but also that on curved surfaces it can maintain only partial coherence across its units (Stella et al., 2019), which endows it with the spin glass character of extended neocortical networks. These two features make the self-organized acquisition of new spatial representations, as explored in rodents, similar to that of abstract conceptual trajectories, as implemented in schemata. The challenge becomes that of understanding how schemata can latch onto each other to navigate long concrete or abstract trajectories (Kang and Treves, 2019).