Default network modulation and large-scale network interactivity in healthy young and old adults

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Aging Research

Background:

• Brain networks, including default, attention, and control networks, play crucial roles in cognition.
• Age-related cognitive changes are often associated with alterations in brain network activity and interactions.

Purpose of the Study:

• To investigate age-related differences in the activity and interactions of default, attention, and control networks during cognitive planning tasks.
• To examine how young and old adults engage and modulate these networks during autobiographical versus visuospatial planning.

Main Methods:

• Multivariate analysis of brain activity during autobiographical and visuospatial planning tasks.
• Regions of interest defined by intrinsic connectivity networks (default, attention, control networks).
• Comparison of network coupling and modulation between young and old adult groups.

Main Results:

• Both age groups engaged the default network for autobiographical planning and the attention network for visuospatial planning.
• The control network was active in both groups and for both tasks.
• Young adults showed flexible coupling of the control network with default or attention networks depending on the task.
• Old adults exhibited default-to-control network coupling for both tasks and failed to deactivate the default network during visuospatial planning.

Conclusions:

• Older adults demonstrate reduced flexible interactivity between brain networks compared to young adults.
• The inability to deactivate the default network during external cognitive tasks in older adults suggests a diminished dynamic range of network modulation.
• These findings highlight age-related changes in cognitive control and network flexibility rather than global default network dysfunction.