Synaptic plasticity as a substrate of resilience

Introduction. Adverse life experiences promote the development of mental illness such as depression, anxiety or schizophrenia. However, some individuals are capable to overcome adversity, achieving a physical and psychological normal development; this process is known as resilience. Aim. To discuss the neuronal substrates of resilience. Development. We propose that resilience at neuronal level needs systems for representing and evaluating the context (adverse situation) in order to display an adequate behavioural output, and for reorganizing memory associated to the adverse situation in order to tell a new story using the same elements of experience; this is, a system that allows to reorganize neuronal ensembles associated to the adverse memory. In this sense, it is not coincidence that neuronal substrates involving in resilience include the reward-guided behavior system (nucleus accumbens-ventral tegmental area), the emotional system (amygdala-hippocampus), the stress system (hypothalamus-pituitary-adrenal) and the system for context evaluation, representation and discrimination (prefrontal cortex-hippocampus). We emphasize that each adverse experience shapes both the activity of the resilience neuronal system and the behavioral output. Conclusions. We propose that synaptic plasticity in structures for representing and evaluating context is the neuronal substrate of resilience. Specifically, cortico-hippocampal interactions would allow to re-build adverse experiences through the reorganization of neuronal ensembles.