During meditation, incense is said to dissipate negative energy. Burning it helps create a positive state of mind and helps condition the mind to associate typical fragrances, such as sandalwood or frankincense, with meditative calm. Since successful meditation depends on the mental state of the meditator, incense can facilitate one's practice by adding relaxation and clarity.
Whereas a candle has a positive visual impact, certain fragrances impart positive impulses to the brain. More importantly these positive impulses, over time, become a natural [Pavlovian] response to that particular scent. The mind becomes "conditioned" to respond in a particular way when that scent is used. For the best effect the incense used during meditation should be of a special (non-synthetic) type used only during meditation. More>>