Final answer:
Licking and grooming in the context of early life adversity is a model used to study the effects of negative experiences. Research on rats has shown that abusive treatment during the postnatal period can lead to depressive-like symptoms in adolescence.
Step-by-step explanation:
Licking and grooming in the context of early life adversity is a model used to study the effects of negative experiences during the early stages of life. Research conducted on rats has shown that abusive treatment during the postnatal period can lead to changes in brain function and behavior that resemble mood disorders in humans. For example, rat pups who experienced abusive treatment were more likely to exhibit depressive-like symptoms during adolescence. These behaviors were associated with increased activation of the amygdala, a brain region involved in emotional processing.