The geometry of temporal cognitive maps CHRONOLOGY

Experiencing the world and inferring its causal structure rely on the flexible temporal organization of information in the brain, enabling future planning in thoughts and actions. Understanding how the brain maps events in time is essential, yet surprisingly little is known about the neural mechanisms by which the brain represents time and uses it for computations. Based on the observation that complex neural activity accompanies the mental evaluation of time across species, our project aims at testing the hypothesis that the collective dynamics of brain circuits involved in memory generate and organize representation of temporality. To identify the key structures of time representations in the brain, we will record neural activity at different neuroanatomical scales (from neuron to whole-brain) in three species (rodents, non-human primates, and humans) while individuals are behaving in timing tasks of varying cognitive complexity. A geometrical analysis of neural activity will determine the existence of temporal cognitive maps that provide individuals with a mental chronology of experienced events. We will test if the navigation of temporal cognitive maps is involved in tasks where individuals mentally travel in time. Exploiting state-of-the-art artificial intelligence methods to build interpretable recurrent neural network models, we will identify generic processes supporting the emergence of time representations by comparing signatures of theoretical mechanisms with brain activity. Targeted causal manipulation at the single cell resolution will help select precise mechanisms among model-based hypotheses, including the role of local and long-range neuronal connectivity in the establishment of circuit dynamics that develop across time scales. Our synergistic cross-disciplinary team will establish an innovative, biologically-grounded, overarching framework for the representation of time in the brain, its dependence on context, and its relation to memory.