Removal of BDNF before bullying, or treatment with antidepressants after bullying, both removed the behavioral abnormality observed.

One of the cardinal features of addiction is how long-lived it is, ... A key question in the field has been: By what mechanisms do drugs of abuse cause changes in the brain that last this long?

Without BDNF in the circuit, an animal can't learn that a social stimulus is threatening and respond appropriately.

Our study provides insight into how chronic stress triggers changes in the brain that are much more long-lived than the effects of existing antidepressants.

The challenge is to find a way to inhibit BDNF signaling within the reward pathway specifically. The many genes we show that are regulated by BDNF or antidepressants in this pathway may provide clues.

The social-defeat process induced production of BDNF in the reward circuit. Without BDNF in the circuit, an animal can't learn that a social stimulus is threatening and respond accordingly.