The relationship between resting‐state amplitude fluctuations and memory‐related deactivations of the default mode network in young and older adults
J. Kizilirmak, J. Soch, H. Schütze, E. Düzel, Hannah Feldhoff, Larissa Fischer, L. Knopf, A. Maass, Matthias Raschick, Annika Schult, R. Yakupov, A. Richter, B. Schott
Human Brain Mapping April 13, 2023 DOI: 10.1002/hbm.26299 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cross-sectional fMRI study Peer reviewed |
|---|---|
| Sample size | 217 |
| Population | 106 healthy young adults (18–35 years) and 111 healthy older adults (60–80 years) |
| Topics | Default mode network |
| Key findings | Older adults had lower resting-state DMN amplitudes and weaker task-related deactivations than young adults. The negative relationship between resting-state DMN amplitude and the subsequent memory effect in the precuneus was present only in young adults. Among older adults, higher resting DMN amplitude tended to accompany better memory performance, which the authors suggest may indicate the importance of maintained DMN modulation with age. |
Abstract
The default mode network (DMN) typically exhibits deactivations during demanding tasks compared to periods of relative rest. In functional magnetic resonance imaging (fMRI) studies of episodic memory encoding, increased activity in DMN regions even predicts later forgetting in young healthy adults. This association is attenuated in older adults and, in some instances, increased DMN activity even predicts remembering rather than forgetting. It is yet unclear whether this phenomenon is due to a compensatory mechanism, such as self‐referential or schema‐dependent encoding, or whether it reflects overall reduced DMN activity modulation in older age. We approached this question by systematically comparing DMN activity during successful encoding and tonic, task‐independent, DMN activity at rest in a sample of 106 young (18–35 years) and 111 older (60–80 years) healthy participants. Using voxel‐wise multimodal analyses, we assessed the age‐dependent relationship between DMN resting‐state amplitude (mean percent amplitude of fluctuation, mPerAF) and DMN fMRI signals related to successful memory encoding, as well as their modulation by age‐related hippocampal volume loss, while controlling for regional grey matter volume. Older adults showed lower resting‐state DMN amplitudes and lower task‐related deactivations. However, a negative relationship between resting‐state mPerAF and subsequent memory effect within the precuneus was observed only in young, but not older adults. Hippocampal volumes showed no relationship with the DMN subsequent memory effect or mPerAF. Lastly, older adults with higher mPerAF in the DMN at rest tend to show higher memory performance, pointing towards the importance of a maintained ability to modulate DMN activity in old age.
Comparable studies
Other experimental studies on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Functional connectivity of default mode network components: Correlation, anticorrelation, and causality Healthy subjects | 2008 | Observational study using resting-state fMRI and seed correlation analysis | |
| Patterns of Brain Activity Supporting Autobiographical Memory, Prospection, and Theory of Mind, and Their Relationship to the Default Mode Network Healthy subjects | 2009 | Experimental study using fMRI | |
| Dynamic reconfiguration of the default mode network during narrative comprehension Human subjects | 2016 | Experimental study | |
| Broadband Cortical Desynchronization Underlies the Human Psychedelic State Healthy human participants | 2013 | Experimental study | |
| The brain on art: intense aesthetic experience activates the default mode network Human observers | 2012 | Observational study with fMRI and behavioral analysis |
Citations in the library
Cites 3
- A default mode of brain function Proceedings of the National Academy of Sciences January 16, 2001
- Age-related alterations in default mode network: Impact on working memory performance Neurobiology of Aging August 1, 2008
- Effects of aging on default mode network activity in resting state fMRI: does the method of analysis matter? Neuroimage March 12, 2010