Depression could be passed down from mother to child, a new study suggests.
Researchers from the University of California analysed MRI brain scans of adults and children from 35 different families.
The scientists paid particular attention to the structure of the brain's circuitry, known as the corticolimbic system. This part of the brain regulates emotion and influences mental health conditions such as depression.
They found that the corticolimbic system is more likely to be passed down from mothers to daughters rather than from mothers to sons or from fathers to children of either gender.
According to the report, previous research has shown "a strong association in depression between mothers and daughters".
Previous animal studies have also shown that female offspring are more likely to show changes in emotion-associated brain structures, in response to maternal prenatal stress, than males.
However, according to lead author Fumiko Hoeft, this is the first study to use MRI scans in both parents and their children to study brain structure in this way.
She added that the findings do not mean that mothers are necessarily "responsible" for their daughters' depression.
"Many factors play a role in depression - genes that are not inherited from the mother, social environment, and life experiences, to name only three. Mother-daughter transmission is just one piece of it," she said.
"But this is the first study to bridge animal and human clinical research and show a possible matrilineal transmission of human corticolimbic circuitry, which has been implicated in depression, by scanning both parents and offspring."
One limitation of the study is that it does not differentiate between the potential effects of genetics, prenatal conditions and postnatal conditions on brain structure.
But Hoeft and her team plan to use MRI scans to study brain structures in families where children have been conceived and delivered using different types of in vitro fertilisation (IVF) to further the research.
H/T: Eureka Alert