In plain words
Gray matter is the tissue in the brain made mostly of nerve cell bodies. It sits on the outer layer of the brain and in deeper clusters. Researchers measure its volume with brain scans. In a well-known study of first-time mothers, scans taken before and after birth showed less gray matter in several brain regions. The changes were in areas linked to thinking about other people's minds. Fathers and women who had not given birth did not show the same change in that study. Some of the changes were still present two years later, and some areas showed partial recovery. Scientists think these changes may relate to caring for a baby. This is one study, and many questions remain.
The deeper version
Hoekzema and colleagues (Nature Neuroscience, 2017) found gray matter volume reductions in first-time mothers across the medial frontal and posterior midline cortex and in bilateral lateral prefrontal and temporal cortex, regions overlapping the theory-of-mind network. The reductions were absent in fathers and in controls. They were largely stable at two years, with partial hippocampal recovery, and they predicted maternal scores and neural response to the infant. The study is a longitudinal cohort of modest size, and a control design does not exclude every confounder from the pregnancy process itself. Whether the reductions reflect loss, pruning, or a shift in tissue composition, and whether they change function, remain open questions. The imaging findings are correlational.
Where it comes up
- Matrescence: becoming a motherPostpartum: Mind
- Forgetfulness and brain fogPregnancy: Mind and Life
- Postpartum anxietyPostpartum: Mind
What mothers here say about gray matter volume
No one has posted under this term yet.
Sources
- Hoekzema E and colleagues — Pregnancy leads to long-lasting changes in human brain structure. Nature Neuroscience, 2017