Mindfulness is a construct that is difficult to define (see Bishop et al., 2004; Grossman, 2008 & in press a; Kabat-Zinn, 2003; Melbourne Academic Mindfulness Interest Group, 2006). It has been described as a form of participant-observation that is a characterized by moment-to-moment awareness of perceptible mental states and processes that includes continuous, immediate awareness of physical sensations, perceptions, affective states, thoughts, and imagery (Grossman et al., 2004). Definitions of mindfulness from Buddhism and MBTs focus upon a number of qualities that include (a) a deliberate intention to pay attention to momentary experience, (b) a marked distinction from normal, everyday modes of consciousness, (c) a clear focus on aspects of active investigation of moment-to-moment experience, (d) continuity of a precise, dispassionate, non-evaluative, and sustained moment-to-moment awareness of immediate experience, and (e) an attitude of openness, acceptance, kindness, curiosity and patience (see Grossman et al., 2004, 2010; Grossman & Van Dam, in press). Additionally, mindfulness directly involves active development of such qualities as energy, tranquility, and equanimity (e.g., Nanamoli & Bodhi, 2001, note 560). Along similar lines, if somewhat simplified, Bishop and colleagues (2004) distinguish two components of mindfulness: one that involves self-regulation of attention and one that involves an orientation toward the present moment characterized by curiosity, openness, and acceptance.

Mindfulness meditation employs the full range of perceptible experience as possible objects of mindful awareness, for example, bodily or other sensory experience, affective states, thoughts, or images. Illustrative of this approach and often seen as a particularly useful technique is the mindfulness practice of moment-to-moment attending to breathing. The aims of breath awareness within the Buddhist perspective are (among others): (1) to use an observable, easily perceptible and constantly available physical stimulus (the breath) as object of investigation of mind-body awareness; (2) to utilize continuous attention to the breath to improve the capability of moment-to-moment volition-driven concentration; (3) and to employ a rather simple object of observation (which is intimately related to physical mental and emotional functioning) as a starting point for more complex objects of awareness. It should be noted, however, that mindfulness of breathing in itself is a sophisticated, systematic, and multilayered procedure (for further details, see Rosenberg, 2004, and Grossman, 2010, Grossman, in press). Thus, consistent with definition of mindfulness above, a major aim of mindfulness meditation is to cultivate a more accurate view of how the mind operates and to raise awareness of the present moment by means of a process of phenomenological investigation that is inherent to mindfulness practice. MBT has been typically derived from non-Tibetan traditions and practices, particularly the Theravadin tradition (the oldest existing Buddhist school), although mindfulness is also central to other Buddhist traditions as well.

A recent review of the literature suggests that MBT is a beneficial intervention to reduce negative psychological states, such as stress, anxiety, and depression (Hofmann et al., 2010). This review identified 39 studies totaling 1,140 participants receiving MBT for a range of conditions, including cancer, generalized anxiety disorder, depression, and other psychiatric or medical conditions. Effect size estimates suggest that MBT is associated with strong effects for improving anxiety and mood symptoms in patients with anxiety and mood disorders. In other patients, this intervention was moderately effective for improving anxiety and mood symptoms. These effect sizes were robust and unrelated to number of treatment sessions or publication year. Moreover, the treatment effects were maintained over follow-up. These findings suggest that mindfulness-based therapy is a promising intervention for treating anxiety and mood problems in clinical populations.

However, most studies of mindfulness pertain to a certain aspect of Buddhist meditation practice, namely, attending to mental content, such as current feelings, or sensorial experiencing, such as the breath, in a non-judgmental, curious manner (for discussions of mindfulness see Bishop et al., 2004; Grossman, 2008 & in press-a; Kabat-Zinn, 2003; Melbourne Academic Mindfulness Interest Group, 2006). In the Buddhist tradition, there are other very prominent practices that involve other attentional objects and emotional modes of attending to those objects that have been much less discussed, namely loving-kindness and compassion meditation. These practices have only recently been investigated by contemporary psychology researchers.

Loving-kindness meditation (LKM) aims to develop an affective state of unconditional kindness to all people. Compassion mediation (CM) involves techniques to cultivate compassion, or deep, genuine sympathy for those stricken by misfortune, together with an earnest wish to ease this suffering (Grossman & Van Dam, in press; Hopkins, 2001). Both forms of meditation (LKM and CM) are centrally related to, and include the practice of, mindfulness, as noted by many scholars and practitioners from varying traditions, including Theravadin, Japanese, and Chinese Zen (e.g., Bodhi, 2005; Kuan, 2008; Sanharakshita, 2004; Shen-Yen, 2001; Suzuki, 2011).

LKM has been described by Salzberg (1995) as a path of deep spiritual transformation. She wrote:

Similarly, compassion has been described as a path leading to greater awareness. For example, Feldman (2005) wrote:

The goal of this review is to provide a brief historical background, explain the therapeutic procedures, review the experimental and intervention research literature, and discuss the relevance of LKM and CM as adjunctive components of contemporary psychosocial treatments.

These four attitudinal qualities, or emotions, form the foundation of the Buddhist ethical system. However, they are not seen as dictates from a higher authority but rather as characteristics necessary to achieve insight into the workings of our own minds, as well as the world around us, to attain a life free from misery. According to this view, in order to effectively pay moment-to-moment attention to the perceptible (an inherently cognitive act), one needs to cultivate these four qualities. Without their presence, whenever confronted by unpleasant or negative perceptions (e.g., negative self-thoughts, disturbing emotions, or distressing images), one would be highly likely to come into an evaluative or ruminative state of mind and thus no longer be able to imagine or actually experience the emotional state as an object of attention and mindful awareness. Only when we are able to confront difficult sensations emotions or thoughts with a degree of kindness, compassion, and composure, can we attend to the variety and textures of present-moment experiences in a mindful way. Consequently, the four immeasurables, including loving-kindness and compassion, can be seen as attributes that underlie the nonjudgmental aspect of mindful awareness. Without them, negative judgments interfere with sustained mindfulness, whether to the breath or to any other object of awareness.

In many Buddhist practices, LKM and CM are combined together, and such is the case in most psychological studies (e.g., Kabat-Zinn, 1990; Lutz et al., 2009). In the elaborated form of compassion meditation, the meditator conducts a series of contemplations. According to Buddhist tradition (Book 1, uraga vagga [the snake book], cunda kammaraputta sutta [AN 10.176], at each stage the meditation exercise consists of thinking about specific wishes (aspirations) for the other, including the following: (1) may the person be free from enmity; (2) may the person be free from mental suffering; (3) may the person be free from physical suffering; and (4) may the person take care of him/herself happily (see e.g., Chalmers, 2007; The Dalai Lama, 2001). One may begin by first directing this feeling of compassion towards oneself or to others, depending upon what is easiest.

During LKM, the person typically proceeds through a number of stages that differ in the focus of the LKM exercise and also proceeds from easier to more challenging types of contemplation. These include: (1) focus on self; (2) focus on a good friend (i.e., a person who is still alive and who does not invoke sexual desires); (3) focus on a neutral person (i.e., a person who typically does not elicit either particularly positive or negative feelings but who is commonly encountered during a normal day); (4) focus on a “difficult” person (i.e., a person who is typically associated with negative feelings); (5) focus on the self, good friend, neutral person, and difficult person (with attention being equally divided between them); and eventually (6) focus on the entire universe (Buddharakkhita, 1995; The Dalai Lama, 2001). As can be seen from this sequence, typically warm feelings are initially directed toward oneself and then extended to an ever-widening circle of others, ultimately radiating them in all directions (north, south, east, west, and so on), although the order can be changed to accommodate individual preferences.

Each practice, whether LKM or CM, represents an exercise that employs the imagining or actual experience of the emotional state as an object of attention and mindful awareness. The practices should not be seen as mere mechanical repetitions of images or phrases. Rather, by mindfully investigating what occurs when one attempts to generate loving-kindness or compassion, it is presumed that insight is gained into the nature of these emotions themselves, as well as one’s personal relationships to them. Also by turning toward this focus of experience in a kind, open, patient and tolerant manner, a shift in these affective states toward greater loving-kindness and compassion is thought to take place.

A study by Fredrickson and colleagues (2008) investigated the question of whether a modified LKM intervention enhances a person’s daily experiences of positive emotions, which, in turn, may increase personal resources that hold positive consequences for the person’s mental health. The study was conducted at a large business software and information technology services company. Employees who agreed to participate in this study were assigned to receive LKM (n = 102) or were assigned to a waitlist control group (n = 100). The study involved daily assessments of time spent meditating and a range of measures to assess positive and negative emotions. The intervention consisted of six 60-minute group sessions conducted over 7 weeks with 20–30 participants and 1 instructor per group. In the first session, participants received a CD with three recorded guided meditations. In Week 1, participants practiced a meditation directing love and compassion toward themselves. During subsequent weeks, the objects of LKM built from self, to loved ones, to acquaintances, to strangers, and to all living beings. The LKM periods were between 15–20 minutes in duration and were conducted in groups. Each session also included a 20 minute discussion to examine participants’ progress and answer questions, and 20 minutes for a didactic presentation about features of the meditation and how to integrate concepts from the workshop into one’s daily life. Participants were asked to practice LKM at home, with the guided recordings, at least 5 days per week. The results showed that LKM led to shifts in people’s daily experiences of a wide range of positive emotions, including love, joy, contentment, gratitude, pride, hope, interest, amusement, and awe. These increases in positive emotions could be observed both within the trajectories of change in daily emotions over the span of 9 weeks and also 2 weeks after formal training ended. These shifts in positive emotions were relatively small in magnitude. However, over the course of 9 weeks, they were associated with increases in a variety of personal resources, including mindful attention, self-acceptance, positive relations with others, and good physical health. Furthermore, the gains in personal resources led participants to become more satisfied with their lives and to experience fewer depressive symptoms. Interestingly, the effects of LKM were specific to positive emotions, because negative emotions did not show any substantial changes. In contrast, an earlier study by Carson and colleagues (2005) showed that LKM was also associated with a decrease in trait anger, anxiety, and distress. Carson and colleagues (2005) compared an 8-week LKM program (n = 18) with standard care (n = 25) for chronic low back pain. Dependent measures included the participants’ reported pain, anger, and distress. LKM initially involved patients recalling a time when they felt a very positive feeling of connection with a loved one, letting go of the content of this memory while remaining focused on the actual feelings of love and kindness elicited in the present moment by the memory, and employing silent mental phrases to direct these positive feelings, as best as possible, toward the loved one (i.e., may this person be at ease/content/happy/safe and secure) and then toward oneself. During the final minutes of the meditation, patients were asked to rest with attention to any feeling of love that remained from the practice. Note that the focus on affect is somewhat different from the cognitive focus that is more typical of other loving-kindness practices (e.g., Salzberg, 1995).

Over the course of several weeks, this exercise was gradually extended to include directing positive feelings toward a neutral person (e.g., postman, store clerk); toward a person who harmed the patient or was a source of difficulty for them in the past in some way, and who they felt they could forgive to some extent (e.g., disrespectful former boss); and then toward all living beings. Along with the in-session practices of loving-kindness meditation, the protocol included psychoeducation, group discussions, and additional practices, such as body scan exercise that encourages patients to accept their bodies and to feel gratitude for what their bodies have enabled them to accomplish in life. As part of the homework assignments, patients were asked to spend 10 to 30 minutes daily practicing audiotape-guided loving-kindness strategies on their own.

Results from this small randomized pilot trial indicated that LKM reduced pain, anger, and psychological distress to a greater degree than standard care at post-test and follow-up. Multilevel analyses of daily recordings further showed that more LKM practices were related to less pain that day and less anger the following day. However, it should be noted that LKM may have led to a greater reduction in negative emotions as compared to other studies because participants might have had higher negative emotions at baseline. Future, well-controlled, studies would provide valuable information about the therapeutic effects of LKM.

In addition to studies examining the potential clinical utility of LKM, a number of authors have recently begun to examine self-directed compassion. Self-directed self-compassion refers to the compassion about one’s own suffering. The state of self-compassion involves generating the desire to alleviate one’s suffering, healing oneself with kindness, recognizing one’s shared humanity, and being mindful when considering negative aspects of oneself (Neff, 2003; Neff & Vonk, 2009; Thompson & Waltz, 2008). Leary and colleagues conducted a number of studies with undergraduate student populations by using a self-report instrument to measure self-compassion as a trait variable (Leary, Tate, Adams, Allen, & Hancock, 2007). These studies suggest that self-compassion moderates reactions to distressing events involving failure, rejection, and embarrassment. Specifically, Leary and colleagues (2007) observed that individuals with high levels of self-compassion reported less negative emotion when confronting real, imagined, or remembered negative events, were more willing to accept responsibility for negative events, but were less likely to ruminate about unpleasant events compared to individuals low in self-compassion.

Another study by Gilbert and colleagues examined efficacy of the same treatment protocol in people who met criteria for paranoid schizophrenia (Mayhew & Gilbert, 2008). A total of 7 potential participants, all of whom reported experiencing hostile auditory hallucinations, consented to participate. Of these, only 3 completed the treatment. Discontinuation was due to clinical deterioration in most cases. One person discontinued because she felt better. Treatment consisted of 12 1-hour weekly sessions. During treatment, therapists encouraged patients to focus on their difficulties with safety behaviors and become understanding and compassionate to those safety behaviors. Therapy also included a discussion on the function and value of self-compassion, and on the strategies to cultivate self-compassion by generating feelings of warmth and self-acceptance in response to self-critical thoughts. In this context, the therapist helped patients to have empathy for the fear and distress associated with these safety behaviors and to develop tolerance for some of these fears.

In the Buddhist tradition, LKM and CM have traditionally been combined with other meditation practices—such as multi-sensorial mindfulness--and may well be efficacious techniques when added to existing empirically supported therapies, such as cognitive behavioral treatments. A summary with a typology of meditational practices commonly employed as psychotherapeutic adjuncts is presented in Table 1 (for further discussion, see Hinton, Pich, Nickerson, Hofmann, & Otto, in press). This typology is organized in terms of mindset, defined as a certain attentional object viewed with a certain emotion/attitude (e.g., Bishop et al., 2004; Brown et al., 2007; Grossman et al., 2004; Lau et al., 2006; Lutz et al., 2008; Shapiro et al., 2006; Thera, 1962). The typology suggests treatment implications and provides avenues for future research areas. For instance, using neurophysiological and clinical methods, it might be particularly useful to contrast treatment changes that occur during these meditation techniques as compared to more traditional emotion-regulation strategies, especially in regard to social and affiliative measures (Barraza & Zak, 2009).

Despite obvious applications for clinical psychology, LKM and CM have only recently been studied by clinical researchers. Neuroendocrine studies suggest that CM may reduce stress-induced subjective distress and immune response (Pace et al., 2009; 2010). Moreover, neuroimaging investigations comparing expert and novice meditators indicate that LKM and CM enhance the emotional and somatosensory brain representations of other people’s emotions (Lutz et al., 2008, 2009).

The limited empirical evidence from the intervention literature suggests that elements of LKM and CM can be trained within a relatively short period of time. The study by Hutcherson and colleagues (2008), in fact, suggests that even a 7-minute training in LKM can produce small or moderately strong improvements in positive feelings toward strangers and the self. The LKM training period in the other studies with nonclinical populations consisted of six 60-minute weekly sessions (Fredrickson et al., 2008; Pace et al., 2009, 2010). The LKM exercise itself was only 15–20 minutes in duration (e.g., Fredrickson et al., 2008), although the effects were also modest. In clinical studies, the LKM training consisted of 8 weekly 1-hour sessions to reduce chronic low back pain (Carson et al., 2005), 12 weekly 2-hour sessions for treating anxiety, anger, and mood problems using a modification of CM (Gilbert & Procter, 2006) and 12 1-hour weekly sessions for treating paranoid symptoms in patients with schizophrenia (Mayhew & Gilbert, 2008). Therefore, LKM and CM appear to have a positive effect on psychological functioning even after a relatively short period of training time.

It could, nevertheless, be argued that comparisons of studies examining effects of very short-term directing of positive attention with studies of long-term LKM or CM training may not be appropriate because very different mechanisms may be activated by directing LKM for a few minutes to a stranger (Hutcherson et al., 2008) versus a systematic training in which participants spend many hours confronting repeated efforts to send LKM or CM to oneself, loved ones, or even enemies. Examining the effects of these practices in a laboratory by giving brief instructions to novices goes against the very basic Buddhist assumption that these abilities take considerable time and practice to develop (see Grossman, 2010). Therefore, it is quite possible that the training has very different effects when comparing novices with experts who have practiced for decades (as in the studies by Lutz et al., 2008, 2009).

An additional issue relates to the fact that mindfulness meditation is used in the various Buddhist traditions as an important preliminary phase to establish concentration and attention required for LKM and CM (Analayo, 2003; Pandita, 1992; Sheng-Yen, 2001; The Dalai Lama, 2001). When effects upon LKM were examined alone in an intervention trial (Fredrickson et al., 2008), effects upon positive emotions were significant but small, and contrary to major assumptions of Buddhist psychology, there were no treatment benefits upon reduction of negative emotions. This may suggest that CM and LKM techniques require integration with mindfulness practices, and future research in this area is clearly needed.

In sum, existing research studies suggest that LKM and CM are highly promising practices for improving positive affect and for reducing stress and negative affect such as anxiety and mood symptoms. We hypothesize that LKM may be particularly useful for targeting interpersonal problems such as anger control issues, whereas both CM and LKM may be particularly useful for treating relationship problems, such as marital conflicts, or counteracting the challenges among caregiving professions or nonprofessionals who must provide long-term care to a relative or friend. The primary reason for these hypotheses is directly rooted in the Buddhist tradition. The Buddhist tradition conceptualizes metta and karuna as being the two brahma viharas that are incompatible with anger, hatred, envy, and jealousy. And the usefulness of increased compassion for others and oneself should be self-evident in situations of long-term caregiving, whether familial or professional.