Meditation traditions claim that paying attention to internal body sensations increases awareness of them, but scientific evidence is lacking. Experienced meditators (Tibetan Buddhist and Kundalini) were compared to nonmeditators matched for age and body mass index on a heartbeat detection task, a standard measure of interoceptive awareness. Contrary to predictions, meditators showed no superior performance across several sessions and respiratory conditions. However, meditators consistently rated their interoceptive performance as better and the task as easier. These results suggest that practicing attention to internal body sensations, a core feature of meditation, does not enhance the ability to sense the heartbeat at rest.
Damage to parts of the brain's default mode network (DMN) impairs autobiographical memory. In 92 patients with focal brain lesions, damage to the medial prefrontal cortex, posterior cingulate cortex, inferior parietal lobule, or medial temporal lobe led to memory deficits. Semantic and episodic autobiographical memories rely on largely distinct neural regions: semantic deficits followed left medial prefrontal and medial temporal damage, while episodic deficits followed right-sided damage, with overlap only in the right inferior parietal lobule. These results provide neuropsychological evidence that the DMN is necessary for autobiographical memory and clarify its role in self-referential processing.