Sesshin

Seven-day sesshins are held several times a year at many Zen centers, especially in commemoration of the Buddha's awakening to full enlightenment (anuttarā-samyak-saṃbodhi).

At this Rohatsu sesshin, practitioners seek to relax and quiet the mind to the point of cessation of mental chatter and emotional impulse, samadhi, kensho, or satori.

Traditional sesshin are more intensive, with meditations lasting 30–60 minutes each, with an absence of any rest or work breaks and sleep limited to less than five hours a day.

This is called yaza and is much revered as a particularly effective time to meditate when the thinking mind and ego lack the energy to derail practice.

[3] Sesshin can lead to deep experiences of awakening that may at times be somewhat traumatic, akin to a "spiritual emergency" or symptoms of Kundalini Syndrome.