Meditation
People who have practiced meditation for many years exhibited increased gamma brain wave activity in a recent study. Gamma waves represent brain activity involved in attention, learning, and memory. Help your mind stay nimble by taking a meditation course or boning up on meditation with a book.
There are many schools of meditation. Beginners may want to learn about meditation through classes, DVDs, or books. For a quick start on your own, try sitting quietly and focusing on a soothing thought, word, or image while you remain still and breathe deeply. Whenever your mind strays, note the thought or sound that drew your attention, but then gently bring your mind back to your original focus. After 20 minutes, you may begin to feel some of the benefits of meditation. Studies show that regular meditation may reduce heart rate, blood pressure, respiration, depression, stress, and anxiety. Now, a new study reveals that long-term practitioners of Buddhist meditation exhibit increased gamma brain wave activity, a type of brain wave associated with enhanced focus, concentration, learning, and memory.


I only know one form of meditation at the moment, my dad taught it to me, and I can only maintain it for about 15 minutes. Its very similar to what you describe.
I sit in good posture. Forget the movies, crossing feet on top of legs and ring in your hands doesn't matter, just upright, let the blood flow at its best. Be aware of your breath, in and out. Instead of ignoring any physical discomforts, allow yourself to feel them. Find a spot on a wall or landscape directly in front of me and stare at it, never diverting so much as a glance. Let go of my thoughts, just stare. Hear without listening to everything around me, that is, hear everything, but don't focus on any single sound. Open up my peripheral vision without breaking my stare, be aware of my surroundings. Thoughts will come, but simply watch them, that is let them come and pass, as if a bird flying by, without a second thought. Stay in the moment, the second, not glancing at a past sound, or a future possibility. Let go of all focus, and feel the world around you, your body and mind a part of the experience, setting your spirit free from the constant compartmentalizing of life that egocentric thought brings.
I've practiced this in the past, I will not lie, it has been awhile, but I am also being honest in saying the results are as apparent as the sun rising and setting. You will be more aware, more mindful, and more in the moment for hours later, perhaps the rest of the day.
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