I often suggest meditation to Highly Sensitive People (HSP) to reduce and recover from over-stimulation. But I realize that when someone recommends meditation or says that they meditate, it can sound like meditation is one, monolithic concept. They may as well be saying, “I recommend pills.” There are many kinds of meditation, just as there are many kinds of pills.

Each form of meditation has its purpose. If you already meditate, great. (But there’s no harm in trying other methods or doing two.) They are listed below from moderately relaxing to most relaxing, given the parts of the brain being used. This is in keeping with HSPs’ need for effective, “efficient” downtime. I also included each method’s spiritual goal.

• Guided meditations. After relaxation instruction, you are guided in how to use your imagination to achieve a goal. Often inspired by depth psychology (e.g. Carl Jung), practitioners can take you to a deeper, perhaps more spiritual part of yourself (“You are at the edge of a deep forest, there is a path into it, someone is waiting in the forest to guide you through this dark place…”). Done alone it is called “Active Imagination.” Guided meditation can also be used, for example, to help you imagine how to break a habit. But even though your body is relaxed, your brain is still pretty busy.
• Guided meditations for relaxation. Someone speaks in a soft voice (in person or audio), instructing you how to relax. There are countless methods. (For example: “Take five deep breaths, in through your nose and out through your mouth, then bring your attention to your center, around your navel, feel the warmth there…”). It's best if you can learn to do the method by yourself so that your brain is not busy listening. But it is still busy.

Now we go to the forms of meditation studied for the types of brain waves they produce. 

The following three also all share the goal of “awakening” or “enlightenment.”

• Meditations involving focused attention, concentration, or contemplation. Example: Zen Buddhist meditation, sometimes on a koan. Or counting breaths, coming back when a thought interrupts your count. Or repeating a phrase, perhaps about loving kindness. Or focusing on a candle or different object. If your mind wanders, you bring your attention back. Proper breathing and posture (cross-legged on a pillow without back support, if possible) are paramount. The goal is to slip into stillness, satori, “no-mindedness,” without thoughts or feelings, and to maintain this increasingly outside of meditation until one is enlightened (reached nirvana). The associated brain waves are Beta and Gamma, found during focused attention.
• Open monitoring or mindfulness-based meditations, usually derived from various forms of Buddhism, involve observing breathing, thoughts, or other content of ongoing experience without an emotional reaction. Again, try to sit in an upright posture without back support. The goal is to become reflectively aware of the contents of your mind without judgment, beginning to see the personal self as impermanent, an illusion, and what is real as pure dynamic emptiness, the “now.” Perfect calm and objectivity, whatever is going on, would be enlightenment, although instructors separate from Buddhism downplay that goal. The associated brain waves are Theta, found when monitoring internal processes, indicating that the brain is more relaxed than during focused attention.
• Automatic self-transcending practices. For Transcendental Meditation (TM) and Christian Centering Prayer (CCP), sit in whatever way is comfortable and lie down if sleepy. Although you use a word (CCP) or mantra (a meaningless sound, TM), the goal is for it to become fainter, until it disappears. What is left is more or less pure awareness, with minimal or no thoughts or feelings. Thoughts are not discouraged, however, and they're even considered a necessary component. When noticing thinking, one goes gently back to the word or mantra, moving toward deeper quiet. The emphasis is on "no effort." Enlightenment occurs when the inner restful silence becomes a permanent background to life. (The goals are of all three are similar.) The associated brain waves are Alpha 1, found when the brain is alert yet relaxed, with internalized attention and expectancy. Although TM instruction has a set course fee, financial aid is available.