Western typologies

              Ornstein noted that "most techniques of meditation do not exist as solitary practices but are only artificially separable from an entire system of practice and belief". This means that, for instance, while monks engage in meditation as a part of their everyday lives, they also engage the codified rules and live together in monasteries in specific cultural settings, that go along with their meditative practices. These meditative practices sometimes have similarities (often noticed by Westerners), for instance concentration on the breath is practiced in both Zen, Tibetan and Theravadan contexts, and these similarities or 'typologies' are noted here.

       Bodhidharma practicing zazen.

             

                   Progress on the "intractable" problem of defining meditation was attempted by a recent study of views common to 7 experts trained in diverse but empirically highly studied (clinical or Eastern-derived) forms of meditation. The study identified "three main criteria... as essential to any meditation practice: the use of a defined technique, logic relaxation, and a self-induced state/mode. Other criteria deemed important [but not essential] involve a state of psychophysical relaxation, the use of a self-focus skill or anchor, the presence of a state of suspension of logical thought processes, a religious/spiritual/philosophical context, or a state of mental silence". However, the study cautioned that "It is plausible that meditation is best thought of as a natural category of techniques best captured by 'family resemblances'... or by the related prototype model of concepts".

In modern psychological research, meditation has been defined and characterized in a variety of ways; many of these emphasize the role of attention.

In the West, meditation is sometimes thought of in two broad categories: concentrative meditation and mindfulness meditation. These two categories are discussed in the following two paragraphs, with concentrative meditation being used interchangeably with focused attention and mindfulness meditation being used interchangeably with open monitoring,

direction of mental attention... A practitioner can focus intensively on one particular object (so-called concentrative meditation), on all mental events that enter the field of awareness (so-called mindfulness meditation), or both specific focal points and the field of awareness.

"One style, Focused Attention (FA) meditation, entails the voluntary focusing of attention on a chosen object. The other style, Open Monitoring (OM) meditation, involves non-reactive monitoring of the content of experience from moment to moment."

Other typologies have also been proposed, and some techniques shift among major categories.

Evidence from neuroimaging studies suggests that the categories of meditation, defined by how they direct attention, appear to generate different brainwave patterns. Evidence also suggests that using different focus objects during meditation may generate different brainwave patterns.