Q. I just heard someone mention the three C’s of meditation. Whatever are those and do you meditate?

A. The individual may have been referring to broad categories of meditation types. As I understand them, the three C’s are:

• Concentrative meditation—concentrating on one specific word or mantra. It may include Zen, Transcendental, and Kundalini Yoga.

• Contemplative meditation—pondering a specific idea or concept. It may include Directed, Mindful, Quieting, Stress-reducing meditation forms, as well as some types of prayer.

• Clearing meditation—trying to clear your mind of all thought and thinking of nothing. (Some believe the brain was not designed to be cleared of all thought so one might need to put oneself in a type of trance or work with a teacher to achieve this.)

Many studies have concluded that forms of mindful meditation can enhance brain function and help to combat stress, anxiety, and depression, while increasing optimism, creativity, and vitality. And, yes, I do meditate for the benefits to my brain and immune system. I prefer contemplative meditation.