Hideya Koshino (CSU SB)
Interactions between the Default Mode Network and Executive Network in young and older adults

Research has shown that older adults tend to exhibit decreased activity in the Default Mode Network (DMN) at rest and weaker deactivation during tasks. However, this pattern may also depend on brain regions, as the anterior regions may show greater activation, whereas the posterior regions might exhibit decrease of activity. Previously, we reported the Executive Network (EN) and DMN showed coactivation during task preparation whereas the DMN exhibited deactivation during task execution in verbal and non-verbal working memory tasks in young adults. Here, using fMRI, we investigated whether age-related cognitive decline is related to reduced cooperation and competition between the EN and DMN. Results showed that older adults exhibited reduced DMN activity during task preparation and reduced deactivation during task execution. However, the older adults exhibited higher activity in the EN during task execution. In the functional connectivity analysis, the older adults showed weaker connectivity between the DMN and EN during task preparation than the young group. Our data suggest that the age related cognitive decline is associated with deficits in functional connectivity, weaker cooperation and weaker competition between DMN and EN.