Focus

The untrained mind is at the mercy of events, both external and internal. Thoughts and sensations arise on their own and attention follows, apparently without volition. Naturally, mental focus flits about. Our attention goes where it appears to be needed. If there is a new sound, our attention goes there. If it continues, we get used to it and our mind releases our attention to the next novel thing. As we go through life trying to fulfill our needs, we develop habits of attention. We learn what may gratify our needs and desires and what will not. We will focus attention on those things likely to give us pleasure and those likely to harm us. Things that do neither may be ignored. If the things, including thoughts, that we feel may harm us appear to do so whether we attend to them or not, we may withdraw our attention from them as well. They may remain active but be unconscious.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/spiritual-articles/5396-focus.html
If our attention is continually drawn to thoughts of potential danger, we will be anxious. If it is drawn to thoughts of unfairness, we will be angry or irritable. If our attention is constantly drawn to our failings and our beliefs exclude the possibility of change, we will become depressed. When our mental energy is focused too much on our thoughts and emotions, we can become cut off from our environment, and from our bodies.
Meditation allows us to attain some control of our mental focus. It enables us to direct focus where we habitually would not. It balances our awareness so that we become more aware of our surroundings, our thoughts, sensations, and emotions. As we learn to direct the focus of our attention and become aware of our habits of consciousness, the realm of mental activity becomes more coherent. Thoughts and feelings take on their appropriate sizes and shapes. They appear in context. The monsters of our mind disappear as the light goes on.
In meditation practice, we might focus on an object, such as the flame of a candle. This exercises the mind, just as doing push-ups exercises the muscles. Through repetitively using our muscles they grow strong. Through repetitive practice of concentration our capacity for mental focus grows stronger.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=5396
When we use a mantra in meditation, we make a choice about the content of our conscious mind. We direct the focus of that significant part of brain activity devoted to verbalization. The mantra is a word or phrase that is repeated silently or aloud. It usually has some elevated meaning or significance. Its purpose is to guide our mental focus to a higher level of consciousness. Since we can’t verbalize two things at the same time, the mantra blocks other word-thoughts. If you find yourself caught up in worry or other undesirable thought patterns, repeating a mantra can help you regain control. Since thoughts influence feelings, you can also modify your feeling states through repetition of a mantra.Some meditation practices focus attention, but others take the opposite approach and encourage expansion of awareness. Such an unstructured practice would be to sit quietly just watching the field of awareness—observing thoughts and perceptions as they come and go, but not trying to direct them in any way. Here we are practicing not focusing. It’s a tricky activity, letting go of the natural tendency to point our awareness at one thought or sensory stimulus after another. When we remain alert, but give up focusing and allow mental and physical activity to proceed unhindered and undirected, consciousness tends to expand. At the same time, the boundaries between the rest of creation and us become more permeable. For some, the boundaries may disappear. This state of consciousness is open and unbounded, not focused and not unfocused.

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