Key to maintaining a healthy memory is to remain free, or as free as possible, from stress. Stress has adverse effects on both attention and memory. The relaxation response is a physical state of deep rest that changes a person’s physical and emotional response to stress. Herbert Benson, a physician affiliated with the Harvard School of Medicine and the Benson-Henry Institute for Mind Body Medicine at Massachusetts General Hospital  since the 1960s found that the approach is really no different than that achieved through prayer, chanting, meditation, and repetitive motion. They lower heart rates, blood pressure and oxygen consumption. They can alleviate symptoms associated with conditions such as hypertension, arthritis, insomnia, depression, infertility, cancer, and anxiety. Aging can also be added to this list. Recent research examined how the relaxation response affected cach of the body’s 40,000 genes and found that those who regularly used the relaxation response induced anti-oxidation and anti-inflammatory changes that counteracted the effects of stress on the body.
Eliciting the relaxation response is easy. One sits in a relaxed position with the eyes closed and repeats a word or sound as one breathes. When thoughts stray, just refocus on the breathing and the word repetition. This should be done for 10 to 20 minutes once or twice a day.
Usually anything that breaks the train of everyday thought can evoke this physiological state. So participating in repetitive sports such as running, as well as progressive muscular relaxation, yoga, knitting, and crocheting. Playing musical instruments also work, assuming that you can play well such that you can become one with the instrument also works. Effective techniques can vary from individual to individual, and it is important to find the technique that works best with oneself.
Here are some suggestions as to how to start. This is from the website of the Benson Henry Institute for Mind Body Medicine.
Elicitation of the relaxation response is actually quite easy. There are two essential steps:
1. Repetition of a word, sound, phrase, prayer, or muscular activity.
2. Passive disregard of everyday thoughts that inevitably come to mind and the return to your repetition.
The following is the generic technique taught at the Benson-Henry Institute.
1. Pick a focus word, short phrase, or prayer that is firmly rooted in your belief system, such as “one,” “peace,” “The Lord is my shepherd, “Hail Mary full of grace,” or “shalom.”
2. Sit quietly in a comfortable position.
3. Close your eyes.
4. Relax your muscles, progressing from your feet to your calves, thights, abdomen, shoulders, head, and neck.
5. Breathe slowly and naturally, and as you do, say your focus word, sound, phrase, or prayer silently to yourself as you exhale.
6. Assume a passive attitude. Don’t worry about how well you’re doing. When other thoughts come to mind, simply say to yourself, “Oh, well,” and gently return to your repetition.
7. Continue for 10 to 20 minutes.
8. Do not stand immediately. Continue sitting quietly for a minute or so, allowing other thoughts to return. Then open your eyes and sit for another minute before rising.
9. Practice the technique once or twice daily. Good times to do so are before breakfast and before dinner.
Other techniques for evoking the relaxation response are:
· Progressive muscle relaxation
· Repetitive prayer
· Mindfulness meditation
· Repetitive physical exercises
· Breath focus.
You may want to try more than one technique to find the one that suits you best.
The relevance of the relaxation response to improving memory and warding off cognitive decline due to aging should be obvious. Attention is critical to effective memory, but mental fatigue depletes the amount of attention that can be effectively allocated to memory. The relaxation response allows for the refreshment of attention. Attention needs also to be used selectively as there is simply too much information to attend to effectively. The relaxation response facilitates the ability to attend selectively to the information of interest and to ward off distracting stimuli and thoughts.
 Benson, H., (2008). Genomic counter-stress changes induced by the relaxation response., 2 July edition of PLoS One at http://www.plosone.org.