New research published by Silver Santé Study researchers has revealed that older people who have lower blood serotonin levels have more activity in brain regions associated with emotional reactivity, when they face the suffering of others.

The research, published in Biological Psychology, measured the blood serotonin levels of healthy older adults and then measured brain activity while they watched videos of people suffering. The 135 participants watched a series of documentary video clips showing people suffering both emotionally and physically while inside an fMRI scanner so that the immediate effects could be measured.

Serotonin is a neurotransmitter present in both brain and blood which helps regulate mental well-being and other important physiological functions. Low levels of serotonin are associated with depression. The full details of the study can be viewed here.

Yacila Deza-Araujo, of the University of Geneva, who led the research, said: “These results are very exciting because they show that lower levels of circulating serotonin could also indicate a decreased availability of this neurotransmitter on a brain level. This would explain the higher response of emotion-related brain regions when participants see videos of people suffering”.

 “This is interesting because to date, the relationship between serotonin and emotional brain activity was only investigated with pharmacological interventions and mostly, in younger adults. Our study shows, for the first time, the same association in older adults which is particularly important to understand the higher predisposition to depression and anxiety in this population”.

The Silver Santé Study is a 5-year EU-funded study investigating the mental health and well-being of Europe’s ageing population. It is also investigating whether mental training techniques, such as learning a language or practicing meditation, can help safeguard mental health in later life. To find out more about the study click here.