Bishop et al. regard psychological "mindfulness", broadly conceptualized, as "a kind of nonelaborative, nonjudgmental, present-centered awareness in which each thought, feeling, or sensation that arises in the attentional field is acknowledged and accepted as it is".
They propose a two-component operational definition of "mindfulness".
1.) involves the self-regulation of attention so that it is maintained on immediate experience, thereby allowing for increased recognition of mental events in the present moment.
2.) involves adopting a particular orientation toward one’s experiences in the present moment, an orientation that is characterized by curiosity, openness, and acceptance. (2004:232)
The first mindfulness component of self-regulated attention involves conscious awareness of one's current thoughts, feelings, and surroundings, which can result in metacognitive skills for controlling concentration.
The second mindfulness component of orientation to experience involves accepting one's mindstream, maintaining open and curious attitudes, and thinking in alternative categories (developing upon Ellen Langer's research on decision-making).