Concentration and meditation

Attention with mental force on an object = concentration

Attention without mental force on an object = meditation

Attention on the same object without force for an extended time also creates a state called concentration. Same result, but reached with lesser expenditure of energy.

Attention without force, aka meditation, is initially subject to the impurities and complexities present in the mind-field. They raise distractions and attention moves away from the initial object, as is usual outside of meditation. This movement away also happens due to outside sensations like sounds which cause immediate mental reactions.

In Heartfulness/Sahaj Marg, rejuvenation or cleaning removes the mental sources of distractions, and reduces reactivity.

Training the mind-field in meditation consists of accepting distractions have occurred, every time, and returning to the original object as lightly as possible. The subtlest possible way is to merely recognise the movement of attention. The return is automatic and natural.

Reduction in energy of a mental activity is termed as the conversion - laya - of rajas and tamas into sattva.