Stress is a non-specific response of the body to any demand for change linked with perceived threats. The brain is a target for stress and stress-related hormones. It undergoes functional and structural remodelling in response to stress in a manner that is adaptive under normal circumstances but can lead to damage when stress is excessive. Mindfulness practice reduces stress by improving self-regulation, which includes at least three components that interact closely: enhanced attention control, improved emotion regulation and altered self-awareness.
The neuroscience of mindfulness meditation
Yi-Yuan Tang, Britta K. Hölzel and Michael I. Posner
Nature Reviews Neuroscience | AOP, published online 18 March 2015; doi:10.1038/nrn3916