Learned Safety: A New Behavioral Antidepressant?

Evidence is accumulating that psychotherapeutic treatments have neurobiologic effects and engage neuronal circuits both similar to and distinct from those affected by traditional antidepressants. These researchers conducted an elegant series of mouse experiments to test the behavioral and molecular effects of conditioned inhibition of fear, or “learned safety,” an animal learning paradigm in which a neutral stimulus (a tone) is paired with the absence of an aversive stimulus, creating a safety signal for the animal.

The researchers found that this paradigm of learned safety decreased innate and conditioned fear as well as relieved depressive behaviors in an animal model of depression. It also promoted hippocampal neurogenesis, increased hipp…