Exposure to fine particles during fetal life was associated with a
thinner outer layer of the brain, called the cortex, in several
regions.
The patients, doctors found, usually had widespread brain damage, but two injured areas were especially noteworthy: the
thin outer rind, called the cortex, and the thalamus, a pair of walnut - size lumps in the brain's central core, along with the neural fibers that connect these
regions.