Our ability to store memories improves during childhood, associated with structural changes in the hippocampus and its connections with prefrontal and parietal cortices. New research from UC Davis is exploring how these brain regions develop at this crucial time. Eventually, that could give insights into disorders that typically emerge in the transition into and during adolescence and affect memory, such as schizophrenia and depression.
Located deep in the middle of the brain, the hippocampus plays a key role in forming memories. It looks something like two curving fingers branching forward from a common root. Each branch is a folded-over structure, with distinct areas in the upper and lower fold.
"For a long time it was assumed that the hippocampus didn't develop at all after the first couple of years of life," said Joshua Lee, a graduate student at the UC Davis Department of Psychology and Center for Mind and Brain. Improvements in memory were thought to be due entirely to changes in the brain's outer layers, or cortex, that manage attention and stretagies. But that picture has begun to change in the past five years.
Recently, Lee, Professor Simona Ghetti at the Center for Mind and Brain and Arne Ekstrom, assistant professor in the UC Davis Center for Neuroscience, used magnetic resonance imaging to map the hippocampus in 39 children aged eight to 14 years.
While subfields of the hippocampus have been mapped in adult humans and animal studies, it's the first time that they have been measured in children, Ghetti said.
"This is really important to us, because it allows us to understand the heterogeneity along the hippocampus, which has been examined in human adults and other species" Ghetti said.
Looking at three subregions the cornu ammonis (CA) 1, CA3/dentate gyrus and subiculum they found that the first two expanded with age, with the most pronounced growth in the right hippocampus. Only in the olde
|Contact: Andy Fell|
University of California - Davis