" Contraction is our concentration—the activation of the muscle of the mind’s attention—while relaxation is our becoming distracted as attention is deactivated. We activate intentionally, deactivate unintentionally—inadvertently, unavoidably and repeatedly—and then reactivate the directing of attention to refocus on our chosen subject of attention. See "

― Daniel J. Siegel , The Mindful Therapist: A Clinician's Guide to Mindsight and Neural Integration