There is strong scientific evidence indicating that faith and prayer may help us with experiencing greater health physically, mentally and psychologically. Many studies have been published in both medical and psychological journals supporting the positive effects of prayer and faith. But some of the studies related to prayer have mixed results depending on the type of prayer, the demographic and the methods and means its effects were being measured. So, it is important to follow these studies with a critical mind to be able to see why they came up with their conclusions. But overall most conclusions are supportive of the positive influences of prayer and faith on human health and functioning.
Physician and researcher Larry Dossey, M. D., in his book "Prayer is Good Medicine," discusses how praying for oneself and others can have a scientifically measurable healing effect on illness and trauma.
When it comes to the types of prayer, there are different types. For the major religions like Christianity, Judaism and Islam, prayer is more focused on something "outside of the self," so they pray to God. But the more mystical traditions of these religions like Gnosticism, Kabbalism and Sufism, it seems like they are more focused on the "inside of the self" aspect of the prayer, believing that we all have a divinity inside of us. And then there are Eastern traditions like Buddhism and Hinduism, which focus on mediation rather than prayer.
In regard to science, studies done of brain activities on prayer and meditation have indicated that people who engage in these activities on a regular basis have a change in the frontal lobes.  This is the area that controls concentration and focus. When one is in a state of deep prayer, the parietal lobe's power goes down, which can contribute to a sense of transcendence. Furthermore, it has been indicated that people who pray and meditate on a regular basis have some permanent changes to the brain.  Self-aware people who have been meditating with clear intention for 15 years or more seem to have thicker frontal lobe than non mediators.  The frontal lobes are involved in motor function, problem solving, spontaneity, memory, language, initiation, judgment, impulse control, rationality and social and sexual behavior.
Prayer and meditation can influence our state of mind, which then have an effect on our state of body. It can help with anxiety, sadness, blood pressure, sleep, digestion and breathing. It also can influence thinking. These, overtime, can change the brain activity and ultimately the subjective and objective experiences of us in the world.
There are two general types of prayer: personal or individualistic and group or collective. Logically, if one is good, two is better. When a group of people meditate or pray together with the same clear intentions, self awareness and enough focus and concentration, then the effect could be even more positive. Historically, there have also been social impacts to the collective prayers from the Baptist congregation to the Islamic Salaat.
Now if you feel like prayer or meditation may be beneficial to you, a few points that you may want to consider while praying:
1. Based on my personal experience as well as information I have gathered through research on the subject, it seems like a combination of both collective as well as individual prayers may work more positively. You can expand your experience with mixing different methods of prayer and meditation that seems closer to your heart. As always, you have to learn the content of your heart by knowing who you are before you know what may work for you. The more self aware you are, the more aware of your intentions you become and the more profound the result of your prayer would be.
2. If you are doing a personal or an individualistic prayer, focus and work on connecting to your higher self rather than functioning from your ego. Be clear with your intentions and why you are praying so there are no disappointments. In addition, set specific times and a safe and clean place that makes you feel good and helps you concentrate. Self discipline is important.
Also, what I have noticed work is that you can use your pray time as your time to process your emotions. A place where you feel secure to cry, let go of anger, release stress and tension and let go of your unspoken words. Imagine yourself in a bubble of protective energy and just say what is on your mind, process and release the negative, focus on the positive and feel a sense of appreciation for the things you already have and may take for granted. At the same time, you can practice compassion and feel connected to something bigger than you.
You can use tools to stimulate your senses and give you more of an internal focus; for example, lavender to stimulate your sense of smell, a flower or candle, or anything you value and gives your sensations a good feeling. This is your space, design it as you wish, but don't get attached to anything around you. Just connect, focus and feel protected.
3. If you are doing a collective or group prayer, make sure you join a group with uncontaminated and clear purposes. A positive group or institution would not make you feel like your beliefs or method of prayer are superior or "the only way to God." It is not focused heavily on the commercial aspects of selling spirituality; instead, it gives the message of global unity, and encourages personal growth. In addition, such an institution or group supports individuation and accountability.
At the end, as we are expanding, we need to focus on the unity of humanity as a species, and we need to form and find groups that encourage acceptance, productivity, positivity, accountability, tolerance and emotional and physical health. Join groups and institutions that welcome science and wisdom and look at spirituality as a whole. Try not to be attached to any specific group, just connect, learn and grow. If possible, try different institutions just to observe and learn from them. Find whatever positive you can get, while being objective and aware of any red flags. This will help you with your growth process.
At the end, prayer and meditation are like anything else in life. If used with knowledge, awareness and the right intention, they can benefit you. But at the same time, they may become counterproductive if they give you a sense of false hope and radical optimism, or if they get you into a blind group attachment mode. They are positive if they help you with having more focus, having motivation to find a deep meaning, becoming more moral, patient, tolerant, accountable, responsible, objective and rational.
 Andrew Newberg, "How God Changes Your Brain" -- neuroscientist, University of Pennsylvania
 TIME, "The Biology of Belief" by Jeffrey Kluger
Roya R. Rad, MA, PsyD
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