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Understanding depression and anxiety

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The figure uses horizontal bars to show the levels of sensitivity or vulnerability to the effects of stress of the amygdala, prefrontal cortex and hippocampus over the human lifespan. The horizontal timescale is marked in years at: 2, 8, 18, 30, 60, and 90, and labelled with the corresponding stages of growth, as follows: before birth (prenatal), birth, babyhood/childhood, adolescence, adulthood, and ageing. The figure shows that both the developing amygdala and hippocampus are sensitive to the effects of stress until birth, while the developing prefrontal cortex remains sensitive up to 8 years of age. There is particularly rapid growth and increasing vulnerability to the effects of stress of the hippocampus between birth and 2 years of age, of the prefrontal cortex during early adolescence, and of the amygdala throughout adolescence and into early adulthood. The period of most rapid brain decline and potentially highest vulnerability to stress begins around 40 years of age for the hippocampus; about 10 year later for the prefrontal cortex, and after the age of 60 for the amygdala.

 3  The life cycle model of stress