Nancy and Peter Meinig Family Investigator in the Life Sciences, Assistant Professor
He studied Biology and Physics in the Universities of Sevilla and Madrid (Spain). He earned his PhD at the Complutense University of Madrid in 2015 investigating the biophysical basis of brain oscillations and developing mathematical tools to analyze them. During his postdoc, in the laboratory of Gyorgy Buzsaki at NYU, he investigated the hippocampal network mechanisms of navigation and memory in behaving rodents and developed novel optogenetic methods for closed-loop manipulation of neural dynamics.
The main goal of our research is to understand how neuronal dynamics support complex cognitive functions. The fine-tuned coordination of different neuronal populations in distributed brain circuits support this process. A major obstacle to answer this question are the limitations imposed by current technology, thus, part of our efforts are devoted to develop new methods for a more precise interrogation and manipulation of brain circuit dynamics.
To learn from individual experiences, animals must be able to extract common principles and apply them to new instances, that is, to generalize. This generalization process allows animals to perform inferences and make predictions about possible outcomes of their actions. We hypothesize that such predictive inferences rely on internal models of the world (or ‘cognitive maps’), which are supported by the same neural circuits and mechanisms as spatial navigation.
A brain region necessary for memory and spatial navigation is the hippocampus. Our overarching hypothesis is that the role of the hippocampus is to generate a predictive model of the world in the form of structured sequences that bind together pieces of information that have a causal association, such as discrete places along a trajectory or successive events in time. But these sequences will only be useful if they can be read out by downstream structures. Coordination between the hippocampus and associated cortical areas is necessary for memory-guided behavior, and its impairment in neural disorders leads to cognitive deficits. We want to understand how the rest of the brain reads-out the hippocampal memory code and uses it to guide behavior.
To date, these questions have remained elusive due to the lack of simultaneous cell ensemble recordings across multiple implicated brain regions together with specific causal manipulations of behaviorally-linked neural patterns. We tackle these questions by developing and applying cutting-edge techniques such as complex behavioral tasks in rodents, large-scale silicon probe recordings with closed-loop optogenetic manipulations, cellular imaging, circuit mapping, computational analysis and theory.
- Sharif F, Tayebi B, Buzsáki G, Royer S, Fernández-Ruiz A. (2020). Subcircuits of deep and superficial CA1 place cells support efficient place coding across heterogeneous environments. bioRxiv
- Oliva A, Fernández-Ruiz A, Leroy F, Siegelbaum S. Hippocampal CA2 ripples reactivate and promote social memory. Nature, in press.
- Fernández-Ruiz A, Oliva A, Fermino de Oliveira E, Rocha-Almeida F, Tingley D, Buzsáki G. (2019) Long-duration Hippocampal Sharp Wave Ripples Improve Memory. Science 364(6445),1082-1086.
- Senzai Y, Fernández-Ruiz A, Buzsáki G. (2019) Layer-specific physiological features and interlaminar interactions in the primary visual cortex of the mouse. Neuron 101,1-14.
- Fernández-Ruiz A, Oliva A, Nagy GA, Maurer AP, Berényi A, Buzsáki G. (2017) Entorhinal-CA3 dual-input control of spike timing in the hippocampus by theta-gamma coupling. Neuron, 93:1213-1226.