ABSTRACT
Animal and human research has shown that stress has an impact on a wide range of components within the brain including: the hypothalamic–pituitary–adrenal axis; the structure of the hippocampus; the structure and function of the amygdala and frontal cortex; and the functioning of neurotransmitter systems including dopamine and serotonin. Elevated levels of glucocorticoids in response to stress may lead to necrosis or the death of neurons in the hippocampus, and prevent the growth of synapses, the growth of neurons, and the development of white matter in multiple parts of the brain. Stress during infancy, childhood, adolescence, and adulthood has been shown to impact serotonin neurotransmission in rodents. In line with findings from rodent and non-human primate studies, a number of investigations have shown that early childhood stress is associated with reduced serotonergic functioning in adulthood. The combination of the short allele and stressful life events may also have implications for brain structure and functioning.
