Classifying different meditation techniques is essential for the progress of meditation research, as this will enable discerning which effects are associated with which techniques, in addition to supporting the development of increasingly effective and efficient meditation-based training programs and clinical interventions. However, both the task of defining meditation itself, as well as defining specific techniques, faces many fundamental challenges. Here we describe problems involved in this endeavor and suggest an integrated model for defining meditation. For classifying different meditation techniques, we draw on classical, contemporary, and holistic systems of classification. We analyze different techniques and propose that all meditation techniques are based on a specific set of activities, that is: focusing, releasing, imagining, and moving in relation to an object of meditation, including fields of experience. Meditative activities can be combined and unified in the activities of observing, producing, and being aware. All meditative activities are unified in awareness of awareness. Defining specific meditation techniques may be done by specifying which activities and objects are involved. The advantage of our approach is that it can potentially account for the inner workings of all current systems of classification and hence it lays the foundation for formulating an overarching system of meditation that can guide future research and practice.

Meditation has been integral to human culture for millennia, deeply rooted in various spiritual and contemplative traditions. While the field of contemplative science has made significant steps toward understanding the effects of meditation on health and well-being, there has been little study of advanced meditative states, including those achieved through intense concentration and absorption. We refer to these types of states as advanced concentrative absorption meditation (ACAM), characterized by absorption with the meditation object leading to states of heightened attention, clarity, energy, effortlessness, and bliss. This review focuses on a type of ACAM known as jhana (ACAM-J) due to its well-documented history, systematic practice approach, recurring phenomenological themes, and growing popularity among contemplative scientists and more generally in media and society. ACAM-J encompasses eight layers of deep concentration, awareness, and internal experiences. Here, we describe the phenomenology of ACAM-J and present evidence from phenomenological and neuroscientific studies that highlight their potential applications in contemplative practices, psychological sciences, and therapeutics. We additionally propose theoretical ACAM-J frameworks grounded in current cognitive neuroscientific understanding of meditation and ancient contemplative traditions. We aim to stimulate further research on ACAM more broadly, encompassing advanced meditation including meditative development and meditative endpoints. Studying advanced meditation including ACAM, and specific practices such as ACAM-J, can potentially revolutionize our understanding of consciousness and applications for mental health.

Objectives: The jhānas are series of advanced concentrative absorption meditative (ACAM) states brought about by meditation. While previously cultivated mostly in monastic settings, a series of modern meditation manuals both openly discuss the jhānas and describe how they may be attained by laypeople. Simultaneously, the phenomenological and neuroscientific investigation of the jhānas is advancing. Although the descriptions of the jhānas in contemporary jhāna manuals to some degree overlap with one another, there are also significant disagreements. Here our objectives are to identify common features of jhāna in meditation manuals, to identify and discuss disagreements, and to offer an account of jhāna that is both comprehensive and consistent. Methods: A literature search and review was conducted. The search resulted in eight meditation manuals that provide phenomenologically rich accounts of the full range of the jhānas. Common characteristics and discrepancies in the different accounts of the jhānas have been identified by comparing terms and descriptions. Results: We offer a general definition of jhāna, distinguish three types of jhāna, and investigate phenomenological dimensions that may be necessary to address in order to comprehensively articulate the experience of ACAM. Conclusions: To ensure scientific rigor, the study of jhāna needs to be informed by both commonalities and differences in the existing accounts of jhāna. While differences exist, these may also be systematically unified in a way that yields a comprehensive account of ACAM.

Meditation research tends to be focused on positive effects. Recent studies, however, have uncovered a range of potential negative effects, which may be more prevalent than one would expect. Several different conceptions of “negative effects” exist, and such effects are variously termed “challenging”, “unpleasant”, “adverse”, and “harmful”. Before work on a unifying conception of negative effects can begin, the notion of “meditation hindrances” needs to be clarified. Research on meditation hindrances is very scarce. Traditional Buddhist texts and more recent meditation manuals treat different kinds of meditation hindrances, defining them as reactions that impair or halt spiritual progress generally and access to absorption states specifically. Different strategies have been devised as means to renounce or counteract hindrances. However, one influential idea consists of taking a hindrance as the way to liberation, which either makes the distinction between positive and negative ambiguous or collapses it. This makes it questionable whether a unified conception of “negative effect” can be maintained at all. This article gives an overview of the concept of meditation hindrances and discusses both the problems and the potential benefits inherent in the idea of relativizing the distinction between negative and positive effects. Such an idea may be either harmful to practitioners or their greatest asset.

Research on meditation and mindfulness in relation to challenging effects can be understood as consisting of at least two waves: The first wave focused on the efficacy of mindfulness and more broadly the clinically positive effects of meditation. The second wave mainly focused on increasing methodological rigor and uncovering underlying mechanisms. Research on the different kinds and prevalence of potential negative effects was also initiated in this second wave. We propose that future research needs to include the investigation of processes of transformative psychological growth that lead up to and result from advanced meditation and involve complex relationships between positive and challenging effects. Such research is part of a third wave of meditation research, which mainly focuses on advanced meditation. The central point of our argument is that “negative” experiences may be essential to meditative growth. However, it is difficult to define what a negative effect is when considering traditional contemplative perspectives. To conceptualize negative effects, we distinguish between objective and subjective happiness and define “negative effect” as that which overall contributes to both objective and subjective unhappiness. The resulting view represents a common-ground framework that incorporates both psychological and contemplative perspectives.

The history of philosophy gives us many different accounts of a true self, connecting it to the essence of what a person is, the notion of conscience, and the ideal human being. Some proponents of the true self can also be found within psychology, but its existence is mostly rejected. Many psychological studies, however, have shown that people commonly believe in the existence of a true self. Although folk psychology often includes a belief in a true self, its existence is disputed by psychological science. Here, we consider the critique raised by Strohminger et al., stating that the true self is (1) radically subjective and (2) not observable, hence cannot be studied scientifically (Strohminger et al., 2017). Upon closer investigation, the argument that the self is radically subjective is not convincing. Furthermore, rather than accepting that the true self cannot be studied scientifically, we ask: What would a science have to look like to be able to study the true self? In order to answer this question, we outline the conceptual nature of the true self, which involves phenomenological and narrative aspects in addition to psychological dimensions. These aspects together suggest a method through which this concept can be investigated from the first-person perspective. On a whole, we propose an integrative approach to understanding and investigating the true self.