Modulation of effective connectivity in the default mode network at rest and during a memory task
Xingfeng Li1, Elizabeth G Kehoe, Thomas Martin McGinnity
11 Perinatal Imaging Department, St Thomas' Hospital, King's College London , London, United Kingdom .
Brain Connectivity
|November 13, 2014
Summary
Effective connectivity within the default mode network (DMN) changes during memory tasks in older adults. Stronger DMN connectivity at rest and during tasks correlates with better memory performance.
Area of Science:
- Neuroscience
- Cognitive Neuroscience
- Neuroimaging
Background:
- The default mode network (DMN) is modulated by cognitive tasks and performance.
- Previous studies focused on DMN activation, with limited research on effective connectivity modulation during tasks in older adults.
Purpose of the Study:
- To examine changes in DMN effective connectivity between rest and a memory task in healthy older adults.
- To investigate the relationship between DMN effective connectivity modulation and memory performance.
Main Methods:
- Functional magnetic resonance imaging (fMRI) during resting state and an emotional face-name encoding task.
- Effective connectivity analyses of the DMN.
Main Results:
- During rest, the DMN showed strong self-influence, with significant connectivity between the posterior cingulate cortex (PCC) and hippocampus (HP).
- During the memory task, DMN self-influence persisted, with significant connectivity from PCC, HP, amygdala (AM), and parahippocampal region to other DMN regions.
- Effective connectivities from PCC, HP, and AM correlated linearly with memory performance.
Conclusions:
- Superior memory ability in older adults is associated with effective connectivity within specific DMN regions.
- These findings highlight the role of DMN effective connectivity, both at rest and during cognitive tasks, in memory function in aging individuals.
