State Effects of Two Forms of Meditation on Prefrontal EEG Asymmetry in Previously Depressed Individuals

Both mindfulness breathing meditation and loving-kindness meditation shift brain activity toward greater left prefrontal activation, which is linked to approach motivation and positive emotion, in people with a history of depression. A 15-minute session of either meditation produced this change, and the effect depended on each person's tendency to brood. Those who ruminate a lot responded better to breathing meditation, while those low in brooding responded better to loving-kindness meditation. A comparison with a rest group showed the changes were not just due to time passing. The findings suggest both types of meditation can benefit previously depressed individuals, but the best choice may depend on the person's brooding tendency.

Study at a glance

Abstract

We investigated state effects of two forms of meditation on electroencephalography prefrontal α-asymmetry, a global indicator of approach versus withdrawal motivation and related affective state. A clinical series of previously depressed individuals were guided to practice either mindfulness breathing meditation (N = 8) or a form of meditation directly aimed at cultivating positive affect, loving kindness or metta meditation (N = 7). Prefrontal asymmetry was assessed directly before and after the 15-min meditation period. Results showed changes in asymmetry towards stronger relative left prefrontal activation, i.e., stronger approach tendencies, regardless of condition. Further explorations of these findings suggested that responses were moderated by participants' tendencies to engage in ruminative brooding. Individuals high in brooding tended to respond to breathing meditation but not loving kindness meditation, while those low in brooding showed the opposite pattern. Comparisons with an additionally recruited "rest" group provided evidence suggesting that changes seen were not simply attributable to habituation. The results indicate that both forms of meditation practice can have beneficial state effects on prefrontal α-asymmetry and point towards differential indications for offering them in the treatment of previously depressed patients.