Normal aging reduces the ability to suppress low-frequency oscillations and decreases functional connectivity within the default mode network (DMN) during a working memory task. Older adults showed weaker coupling between the posterior cingulate and medial prefrontal cortex, and this coupling strength correlated positively with performance. The posterior cingulate was also negatively coupled with task-related regions like the dorsolateral prefrontal cortex and cingulate. These changes may reflect a deficit in cognitive control that impairs resource allocation to the task.
Regular Zen meditation practice may protect against age-related declines in brain structure and attention. In a comparison of 13 regular Zen meditators and 13 matched controls, only the control group showed the typical loss of gray matter volume and reduced attentional performance with age. Meditators showed no significant correlation of either measure with age. The protective effect on gray matter was strongest in the putamen, a brain area involved in attention. The findings suggest that regular meditation practice may have neuroprotective effects that reduce cognitive decline during normal aging.