Prof. dr. Steven Kushner
Professor of Neurobiological Psychiatry, Erasmus MC, Rotterdam

Over a century of neuroscience has identified specific brain regions that are required for the acquisition and long-term storage of a learned association.  However, within a given brain region, only a subset of neurons undergoes identifiable plastic changes. Computational models of learning also predict that for every experience encoded by the brain, only a minority of neurons are modified in order to preserve a high capacity for information storage. Our studies now demonstrate a novel mechanism by which neurons in the lateral amygdala compete for participation in the neuronal network encoding a fear memory.  Further, we demonstrate that a stable fear memory requires the integrity of these selected lateral amygdala neurons. Together, our results highlight a critically important property of memory formation, and distinguish mechanisms of neural plasticity influencing the acquisition and maintenance of an engram.