Magnetic resonance imaging was used to assess cortical thickness in the brains of 20 participants with extensive Insight meditation experience, which involves focused attention to internal experiences. Brain regions associated with attention, interoception and sensory processing were thicker in meditation participants than matched controls, including the prefrontal cortex and right anterior insula. Between-group differences in pre-frontal cortical thickness were most pronounced in older participants, suggesting that meditation might offset age-related cortical thinning. The thickness of the two regions correlated with meditation experience.