Researchers from the Barcelona Institute for Global Health analyzed data from 3,251 children in the Netherlands.
The children were followed from pregnancy through childhood.
The researchers compared temperatures during pregnancy and the first years of life with MRI scans of the children's brains taken when they were 10 and 14 years old, HealthDay reports.
Possible explanations
According to the study, published in the journal Environment International, high temperatures may affect blood flow to the placenta and the developing fetus.
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The researchers also suggest that heat may influence the body's stress hormones and the neurotransmitter serotonin, both of which play a role in brain development.
However, the researchers emphasize that these are only possible explanations. More research is needed before any causal relationship can be established.
A specific brain region
The study did not find changes in all of the brain regions examined by the researchers.
An association was identified only in the thalamus, a brain structure that helps process sensory information and regulate functions such as sleep and consciousness.
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Children who had been exposed to higher temperatures during pregnancy or infancy showed slower development of the thalamus later in childhood.
However, the researchers found no association between these changes and the children's cognitive abilities.
They therefore conclude that the findings should primarily serve as a basis for future research into how rising temperatures may influence children's brain development.
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