Temporal dynamic fluctuations in the aging brain with resting -state functional MRI revealed lower flexibility of the frontoparietal system and compensatory higher transitions among the default mode of the attentional and the default modes.
Dr Jean Chen The aberrant interactions of large, complex intrinsic networks are often associated to aging brain. It remains to be determined how these networks interact and whether they are activated or deactivated over time.
To help interpret the complex brain network changes that underlie aging. We quantified activation levels to determine coactivation patterns (CAPs) and merged them with resting-state functional MRI.
Materials and Methods
The retrospective study, which was from October 2010 to Sept 2013, used rsfMRI datasets from healthy participants at the Cambridge Centre for Ageing and Neuroscience’s (Cam-CAN), data repository to generate CAPs through single-volume temporal-clustering analysis. Spatial clustering analysis was done to capture dynamic coactivation/deactivation within or among primary sensory networks and high order cognitive networks (including frontoparietal network, FPN, attentional network [AN], default mode network]). Spearman partial correlations revealed linear relationships between dynamic metrics, age, and other variables.
614 people were evaluated (mean age, 54+- 18 [SD]; 311 men); ages ranged from 18 to 85 years. There was a negative correlation in the CAPs. The CAPs had negative correlation patterns between DMN and AN (partial correlations r 0.14, p.003). They also remained (partial correlations r 0.10, p =.04), more so with aging. Moreover, the AN CAP and DMN CAP changed more to the AN CAP and FPN CAP as they grew older (partial correlations: r= 0.17, _ .001).
The healthy aging brain is characterized by more flexibility in high-order cognitive networks and primary sensory functions (networks).