The hypothesis is that different exercises within the range of mindfulness practices exert different effects in terms of electroencephalographic activity, expecting different band increases in alpha (activity 7-to 2 Hz), beta (activity more than 13 Hz), theta (activity 4-6 Hz) and delta (activity less than 3 Hz) respectively, as well as changes in the lateralization of the activity (left or right hemisphere). We also expect an improvement in the variables such as mindfulness, self-compassion, positive affect, anxiety, depression and sleep quality.