Early-life stress has been shown to have long-lasting consequences on adult neuropsychology and is a known risk factor for various neuropsychiatric disorders, namely schizophrenia and major depressive disorder. The amygdala, prefrontal cortex, and hippocampus are key brain regions affected by this stress, with the amygdala playing a crucial role in stress activation and memory formation. Animal models provide valuable insights into the neurobiological alterations caused by stress in these regions and are essential to our understanding of stress-related disorders in humans. This paper will analyze the impact of stress on the activation of the amygdala and its effects on the prefrontal cortex and hippocampus, focusing on the utility and necessity of animal studies in research of stress-related pathologies.