For many years we have known that mindfulness meditation has a positive effect on the brain and in the link below is another study to support this. According to Sarah McLean in her book, Soul Centered, in the January 2011 issue of Psychiatry Research Neuroimaging, researchers from Massachusetts General Hospital found that after only eight weeks of meditation for an average of 27 minutes a day, new meditators showed beneficial changes to their gray matter (the physical structure of your brain).
Mindfulness is when you are engaged in and fully attentive to what you are doing at the present moment. So you can practice this anytime, by giving your full attention to when you are brushing your teeth or washing the dishes, for example. Jon Kabat Zinn has written extensively about this in Full Catastrophe Living as well as his other books.