They examined the size of a special region of the brain, the anterior cingulate cortex, that might be involved in controlling stress hormones. In a significant discovery, scientists found that people with a smaller anterior cingulate cortex had higher levels of stress hormones.
Doctors analysed stress hormone levels and brain volume in two groups of ten healthy male volunteers aged 65-70 for the study. Lead author Dr Alasdair MacLullich said: "Doctors have known for several years that ageing, and certain diseases common in ageing like Alzheimer's disease and depression, can be associated with shrinkage of the brain, but this is the first time we have been able to show that increased levels of stress hormones may cause shrinkage of this critical area of the brain.
"This is an important new finding because the anterior cingulate cortex shows damage in ageing, depression, and Alzheimer's disease, and stress hormones are often high in these conditions. The discovery deepens doctors' understand of ageing, depression and Alzheimer's diseases, and will help in the development of treatments based on reducing high levels of stress hormones."
Results of the study are published in the current on-lin
The Journal of Clinical Endocrinology & Metabolism