UCLA researchers have determined that long-term meditation can cause certain areas of the brain to enlarge. Prior to the study, researchers were already aware of the benefits of meditation, such as reducing stress, improving focus, and benefiting the immune system. However, upon observing the MRI brain images of long-term meditators, they discovered growth in the hippocampus and increases in gray matter in brain areas associated with controlling emotions. Researchers explained that due to the above-average gray-matter density of their brains, long-term meditators are more easily able to control their emotions. They next plan to investigate the correlation between meditation and an increased number of neurons in the brain.