Introduction

There are several challenges in examining the relationship between the self and spirituality. Two of the most complex involve just which one of the many forms or types of the “self” is related to spirituality and what form of spirituality is being considered. Spirituality, like religion, encompasses a wide range of human behavior and cognition, ranging from habitual, mundane daily observances and specific metaphysical beliefs to rare ecstatic rituals and experiences of otherworldly encounters.

Traditions in anthropology and religious studies have characterized religious experiences as either cultural or individual, a result of attributing the meaning of a “religious experience” to a particular event. This notion of attributing meaning is apparent in the examination of the related concept of the “sacred” in cross-cultural contexts. Anthropologists have noted that virtually anything can be considered sacred—even a rock, a vegetable, an insect, or an animal—and that it is society (culture) that makes judgments regarding what is sacred and encodes those determinations. This is an extreme of cultural relativism, the notion that religion, spirituality, and the sacred are merely arbitrary cultural traditions.

In direct contradiction to this relativist posture, cross-cultural patterns of spirituality and the relationship of spiritual experiences to neurological functions illustrate that these spiritual dimensions are not just arbitrary cultural variables but often reflect common patterns and similarities across cultures that indicate that their source is not in arbitrary cultural beliefs. The relationship of the self and spiritual experiences to specific brain regions, and in particular the downregulation of the default mode network (DMN) and right hemisphere parietal lobe, illustrates a biological correlate of spirituality. The cross-cultural view of selflessness as a path to spiritual experiences illustrates these neurobiological correlates, reflecting intrinsic functions of our evolved psychology that facilitate spiritual experiences.

With the many forms of self and spirituality, we need a framework for addressing how the self is related to spirituality by linking both to biological processes. This framework could be used as a tool to sort through the diverse cultural conceptions of transcendent experiences (e.g., bliss, love, awe, void, non-duality) to find biological structures underlying their pervasiveness. The evidence presented here employs such a neurophenomenological framework, linking the functions and effects of the brain’s circuitry to the qualities of the experiences.

While both the “self” and experiences of “spiritual transcendence” are associated with specific neurological regions, it is not the specific nodes or regions but rather the global outcome of the neuropsychological processes the regions engage that produce spiritual experiences. Despite a long history of considering the self as a specific entity, contemporary thinking in the neurosciences characterizes the self as a perception that results from interactive processes within circuits and across regions rather than because of the functions of a specific neurological site. Rather than a single neural entity, the self appears to be based on experiences associated with integrated functions that link diverse neurological processes. This view of the self as an experience produced by integrated neurological processes allows for an understanding of the relationship between the brain and the self, as well as spiritual experiences, as involving both the activation and suspension of specific brain processes that normally produce the sense of self and our interactions with the world.

The evidence presented here suggests that spiritual experiences are facilitated by a reduction in right hemisphere parietal lobe activity and the activation of neural circuitry related to the affective core self (ACS). The ACS is a concept describing the ancient, foundational, emotionally driven part of a person’s being, rooted in mammalian subcortical brain structures. It is considered a primary filter for interpreting the world, influencing feelings, and providing a sense of continuity across the lifespan. We show that the right hemisphere primarily mediates ACS information to the cortex, with both the ACS and right hemisphere making neurophysiological contributions to spiritual experiences. However, it is first important to consider the phenomenological relationship between the self and spiritual experiences.

William James’s Concepts of the Self and Spirituality

William James’s perspectives, reviewed here, illustrate the complexity of the issues confronting us in determining just what is the self and how spiritual experiences are in some sense beyond the self. James (1902) proposes two principal parts to the Self, the “Me,” the Empirical Self, versus the “I” or “Pure Ego,” with the “Me” having a spiritual aspect. The “Me,” the objective, known self, comprises Material, Social, and Spiritual selves, the latter being an enduring and intimate inner subjective self that encompasses one’s ideals, beliefs, conscience, and values. This Spiritual self is to James the principal source of one’s spiritual nature and spiritual qualities, as well as the core of personality and essential being. James considers this Spiritual Self to be a higher form of the self, prefiguring transpersonal concepts of post-egoic forms of self.

James (1902) also refers to a “subliminal self” in the context of his psychical research on mediumship, an unconscious psychological domain of the mind operating below conscious awareness that serves as the basis for paranormal abilities and cosmic consciousness. The subliminal self operates in mediumistic spirit communication, providing intuitive information beyond conscious awareness; it is also capable of higher cognitive processes, expressed through insights, inspirations, and creative problem-solving. The subliminal self is a separate “fragmentary secondary personality” capable of acting independently with its own center of will and intention, even influencing the primary self and consciousness by appearing as a spiritual source of knowledge. “Yet some life-changing moments seem to come wholly from another source, appearing as mental states or altered states of consciousness from either deep within a person’s mind or, perhaps, a source beyond the self” (Yaden and Newberg 2022, 3). It appears that James’s famous quote about a special form of consciousness separated from waking consciousness involves not the Spiritual Self but rather the subliminal self, which is the source of visionary experiences.

David Yaden and Andrew Newberg (2022, 3) present James’s broader views of the self and its relationship to spirituality, noting that what constitutes a spiritual experience is nebulous, overlapping with religious, mystical, peak, and self-transcendent experiences. Nonetheless, the idea that these have a relationship to the self is a recurring theme, and the self is a key element in James’s considerations of religion, serving as the connection between the person and the divine. A recurring notion is that spiritual experiences are referenced to the self, and also beyond the self, yet are part of the self, as in James’s concept of a subliminal self, which posits a spiritual presence as part of humans.

As Yaden and Newberg (2022, 136) note in their review of measures of spiritual wellbeing, an explicit reference to the self is present but so is the importance of “something beyond one’s self.” This notion of the spiritual as being beyond the self is central to meditation practices, which produce a reduction of oneself and decentering from it. While some sense of self may temporarily diminish or even disappear during meditation and spiritual experiences, the specific aspect of self that undergoes this reduction is unclear. Furthermore, there appear to be fundamentally different forms of self-loss. Some accounts identify a loss of agency and self-control, while others refer to a loss of bodily boundaries. An experience of losing self-boundaries that leads to an experience of oceanic merging is clearly distinct from the self-loss encountered in out-of-body experiences, often reported as seeing one’s spiritual body from an external perspective. Autobiographical aspects of life history and identity disappear in some spiritual experiences, while others engage with a life narrative and its transformation. Yet across most, if not all, spiritual accounts, it appears that a sense of self is still present that receives or participates in the experience, something that has the spiritual experience when the normal self is absent. Some form of the self seems to be a necessary reference point. Even when one loses all sense of self during spiritual experiences, afterwards, there is the tendency to describe it as if something happened to some aspect of the person. Of course, it is difficult to know what such a description implies about the remaining sense of personal identity that persists even in cases of a complete merging with the environment, cosmos, or God. But even if it seems that the self goes away completely, there is someone, some aspect of the percipient person, who has the experience. One could propose that this experient during a spiritual experience is the spiritual self. This article explores what the biological bases of that spiritual self might be and how its biological functions and characteristics relate to spiritual experiences.

Why Should the Self Be Key to Spiritual Experiences?

This section frames spiritual experience in reference to the self, showing that self-related processes are fundamental to both consciousness and spirituality. A review of neuropsychological research is used to show that spiritual transcendence emerges from self-attenuation—what Brik Johnstone and Daniel Cohen (2019) call selflessness.

The role of the self in spiritual experiences parallels the essential role of the self in consciousness. Consciousness is typically for something, and that is the self as the focus of awareness and the system of auto-reference. By analogy, the experience of the spiritual is typically for something, and that is the self, which serves as the basis for our understanding of the world, including its spiritual dimensions.

If we conceptualize the spiritual in terms of a spiritual entity, the role of the self is also central. A spirit is a social entity conceptualized with characteristics very similar to those of a human’s, with spirits possessing many human qualities. The relationship of spirits to humans, particularly in the form of gods, exemplifies a broad set of social concerns. Understandings of concepts of spiritual entities from the perspective of the evolved psychology and cognitive science of religion see spirits as reflecting functions of innate operating systems that evolved to manage social relations. Spirits reflect our highly developed self-capacities for relating to social others—recognizing social others, inferring their intentions (“mind reading”), and internalizing their expectations into our own qualities, values, and behaviors. Self-capacities are necessary for perceiving others, spiritual entities, and their qualities, which centrally reflect the capacities of the self (i.e., intentions, agency, desires, emotions, morals, goals, communication, etc.). The most significant differences between the self and spirits involve the spirits’ lack of physical bodies, instead being nonphysical agents, and the general presumption that spirits have capacities beyond those of humans (i.e., access to knowledge beyond normal human capabilities).

Selflessness and Spiritual Experiences

Johnstone and Cohen propose that it is not just the self but rather a broader condition of the self called selflessness that underlies experiences of spiritual transcendence. The significance of selflessness for spiritual experiences is attested to in religious traditions worldwide, which, despite diverse conceptual frameworks, generally contend that the loss of some sense of oneself is a key factor in attaining access to spiritual and other transcendent experiences. This self-loss is illustrated in various of Newberg’s publications, which report a decrease in activity in the parietal lobe during spiritual experiences of different traditions, for example meditation for Buddhists and prayers for Franciscan nuns. Both groups reported strong spiritual experiences that included a sense of loss of the self, although they expressed this in distinctive terms reflecting the beliefs of their specific religious tradition.

Johnstone and Cohen (2019) review evidence suggesting that religious practices attenuate the right parietal lobe (rPL), resulting in a reduction in certain aspects of self-functioning and an attenuation of the self, which enhances the experience of spiritual connection. Johnstone and Cohen review neurological findings that show that such experiences of a diminution of one’s sense of self involve changes in the rPL and its management of self-related information. Johnstone and Cohen find that reductions in rPL are associated with reductions in one’s sense of self and an enhanced potential for spiritual transcendence. They summarize their model of selflessness and spiritual transcendence as beginning with a sense of self derived from neuropsychological integration produced through rPL functions. Spiritual experiences occur more frequently with a minimization of this sense of self, which can be compromised by injury, disease, or certain behavioral practices (e.g., meditation). This heightened selflessness leads to experiences that are understood as spiritual encounters or transcendence.

Johnstone and Cohen (2019, 101) conclude that “selflessness operates as a universal neuropsychological foundation for spiritual transcendence across multiple cultures, ethnicities, and faith traditions, even if such experiences are interpreted differently depending on religious context.” “[D]iminishing of the sense of the self experienced during spiritual transcendence is one neurophysiological/neuropsychological link that explains the similarity of such experiences across different faith traditions” (Johnstone and Cohen 2019, 29). This link between selflessness and spiritual experience suggests that it is the suspension of self-processes that enables access to spiritual experiences rather than the self-processes producing the spiritual experience. This is attested to by studies reviewed later that report increases in spiritual experiences and greater engagement with spiritual practices among individuals with right-hemisphere disorders, resulting in a reduction of right-hemisphere neurophysiological functions that cause a decrease in one’s sense of self and increases in selflessness.

Neuropsychology of the Self and Spiritual Experiences

Here we review evidence for the central role of the rPL in integrating self-referential information and how attenuation of these processes facilitates the emergence of spiritual experiences. This loss of parietal inhibition enhances limbic and DMN activity, contributing to core phenomenological features of spiritual and mystical experiences. Research indicates that spiritual experiences depend on suspending ordinary forms of the self, illustrating how spiritual states arise from the attenuation of habitual self-processes.

Johnstone and Cohen (2019) propose that neuropsychological processes based in the right hemisphere provide the integration of diverse sensations and information used to create the sense of a unified experience of self, and that the suspension of such self-processes of the rPL facilitate spiritual experiences. The parietal lobe is a highly connected hub that manages attention, engages in sensory information processing, produces spatial awareness, and engages memory recall, providing key information for the self. Johnstone and Cohen (2019) review evidence of the roles of the right hemisphere, particularly the rPL, in processing diverse forms of self-related information, such as self-awareness, visuospatial and body integration, episodic memory, and other functions essential for the processes that produce the self. The central importance of right-hemisphere functions for self-processes is illustrated by the extensive research establishing the predominant role of the right hemisphere (versus the left) in self-related emotional processing (LaVarco et al. 2022) and self-facial recognition (Keenan, O’Connor, and Pascual-Leone 2001). Self-recognition is a fundamental form of awareness and consciousness, and a template for recognizing the “other.” The right inferior parietal lobe (rIPL) has a central role in processing self-referential information for representation of the physical self through the integration of sensory data with memory and mental processing (Feinberg 2013). Together with the prefrontal cortex, the rIPL connects regions that are crucial for making self/other distinctions and generating subjective self-experiences (Lou et al. 2004).

The Parietal Lobe and the Embodied Self

The embodied self is a basic aspect of the multifaceted self, deeply embedded in biological processes (see Tsakiris and De Preester 2018). The parietal lobe plays a crucial role in the embodied self, as its neural networks connect it with the premotor cortex (PMC) and motor cortex. The embodied self derives from neural operations that integrate interoceptive and exteroceptive impulses, which provide a basis for feelings of having a body (Qin, Wang, and Northoff 2020). The embodied self emerges from the integration of interoceptive processes that have their core hub in the insula and connections with the thalamus. These transmit information from subcortical areas to integrate external environment information and exteroceptive self processes involving insula functions, the anterior medial prefrontal cortex, temporal–parietal junction, and the PMC (Qin et al. 2020).

Parietal lobe functions are fundamental to establishing interoceptive–exteroceptive relations and body awareness, which are crucial for creating and maintaining the spatial representation between the body and the environment that defines the limits of the physical (embodied) self. The parietal–premotor loop functions produce bodily and spatial awareness, spatial self-location, agency, and the sense of presence that constitutes the embodied self. The interactions between the parietal lobe and PMC link perception and action, forming the basis of the embodied self through one’s goal-directed movements, which integrate intention and agency into bodily actions. These connections produce a sense of body ownership and agency, expressed through the actions one intends, which provide the core of the embodied self and its nonverbal sense of self-presence. The PMC supports self-agency and produces a socially embodied self through the actions of the body schema and the activation of mirror neurons. The PMC (and inferior parietal lobule) contains mirror neurons that contribute to forms of social Selfhood, including empathy, mind reading of intentions, and embodied simulation, which produce understandings of social actors and social situations.

The Roles of the Right Parietal Cortex in the Neurology of Spiritual Experiences

Johnstone and Cohen (2019) review studies that indicate some spiritual experiences are more prevalent in people with reduced activity in the rPL. Activity in areas of the right hemisphere is crucial to certain forms of self-related experience, including spiritual experiences (Newberg and Iversen 2003). The role of the suspension of the right hemisphere in spiritual experiences is illustrated in Johnstone and Cohen’s (2019) review of neuroimaging studies, which show that an overall reduction of right parietal cortex activity is associated with increases in spiritual experiences. Roles of the right hemisphere parietal lobe in normal self-functions are illustrated in research on clinical disorders of the self, which indicates that these patients often exhibit extensive damage to the right hemisphere; there are also reports of significantly more spiritual experiences in people who have suffered right-hemisphere brain injury or disease, specifically in the parietal lobe.

Why does reduced neurological functioning in the rPL lead to increased spiritual experiences? Johnstone and Cohen propose that integrated neuropsychological processes involving the rPL, which create a sense of self, are also the foundation for spiritual experiences of transcendence (2019, 15). This is consistent with Eugene d’Aquili and Andrew Newberg (1993) who argue that a reduction in rPL function is a crucial mediator of spiritual experiences. But it turns out that the effect is more nuanced, that it is the loss of rPL self and inhibitory functions that elicit spiritual experiences. This perspective proposes that the spiritual experience is something that emerges when specific right-hemisphere functions, which normally mediate self-experience, are held in abeyance, allowing for more primordial forms of auto-reference to emerge. These and other findings suggest that the emergence of spiritual experiences is associated with the suspension of specific brain functions.

Right Parietal Lobe Inhibition and Inhibition Loss in Spiritual Experiences

The roles of the parietal lobe functions in producing the bodily self and the sense of physical presence illustrate how its dysfunction changes central mechanisms of self-referential processing that are relevant for the psychological processes of spiritual experience. The loss of spatial orientation functions in the parietal lobe is associated with the emergence of intense spiritual experiences, interpreted as involving a loss of one’s sense of a separate self, which results in a powerful experience of connections with others, the cosmos, and even God. The compromise of the parietal lobe’s boundary-defining functions undermines the experience of separateness and allows a sense of merger of the self with the environment (D’Aquili and Newberg 1999). The loss of parietal–premotor connectivity and the contributions from the PMC during spiritual experiences may reflect the dramatic changes in one’s sense of agency from the inability to implement one’s intentions. The PMC functions of forming motor intentions and initiating action are suspended in some mystical states with a sense of reduced agency, characterized by a loss of volitional control, resulting in states of passivity and surrender where one feels influenced by spiritual forces. The downregulation of the rPL leads to the loss of its habitual functions in forming a sense of the physical self and body separate from the environment. The loss of the embodied self leads to a dissolution of the sense of “body-as-agent” and feelings of having boundaries between the self and the world. Of particular importance may be the loss of function of the right angular gyrus in the parietal lobe, which plays a crucial role in distinguishing the self from others and the environment. The reduction in its functions contributes to the sense of unity with spiritual entities that typically accompanies spiritual experiences. Compromising the functions of the temporo-parietal junction, which has a critical role in the formation of the embodied self, would undermine a sense of the body separate from the environment. A frequent aspect of spiritual experiences involving a reduction in the sense of a separate self appears to reflect the abatement of rPL processes that normally sustain aspects of the self.

The notable ineffability and inability to express mystical experiences may also be directly related to the downregulation of the rPL. The rPL connections with the motor and speech production areas (including those in the left hemisphere) are a major connectivity relationship in the brain. Speech production and articulation require several levels of motor planning, including the supplementary motor area (SMA) for speech; the PMC for performing the articulatory movements; and the primary motor cortex for control of the muscle actions of the tongue, jaw, and lips and coordination of their actions with the larynx and diaphragm. Loss of parietal connectivity with these regions would impede the ability to formulate and express ideas about the experience.

The role of rPL inhibition in spiritual experiences reflects the functions it, and especially several of its key components, has as significant regulatory hubs that exercise top-down modulation. In addition to the rIPL, several nodes in the right parietal cortex usually exercise inhibitory influences on DMN (Corbetta, Patel, and Shulman 2008; Leech and Sharp 2013), including the temporoparietal junction (TPJ), which has functions of perspective-taking, theory of mind, and agency, and the posterior parietal cortex, which engages spatial attention and sensorimotor integration. These regulatory functions exert inhibitory control over left-hemisphere regions, including the left frontal language network and verbal processing, as well as the left-hemisphere DMN, limbic areas, sensorimotor cortex, and the visual–spatial network. The loss of regulatory control by the rPL over limbic regions results in the loss of inhibition of this latter region. The loss of rPL inhibition is associated with a range of altered states of consciousness (ASC; such as meditation and spiritual/mystical experiences, psychedelics) as well as specific psychiatric and neurological conditions, including ego dissolution and depersonalization. This disinhibition is expressed in increased limbic salience, characterized by heightened emotional intensity and enhanced meaning-making. A specific effect of the loss of parietal inhibition is the increase in activity in the posterior cingulate cortex and its functions involving self-referential cognition (Leech and Sharp 2013). Reduced inhibition of the amygdala and hippocampus enhances their functions of attributing salience, making ordinary events feel highly significant.

Research suggests that diminished activity in the rPL results in increased connectivity and activity in the DMN and limbic lobe (see Newberg, d’Aquili, and Rause 2001a). The loss of parietal inhibition over the DMN releases its functions, shifting attention inward with increases in introspection and contemplative absorption, enhanced internal imagery, intensified emotional salience and response, and expanded self-reflection in autobiographical memory and narrative thought.

Due to its essential role in spatial body representation, the loss of rPL connectivity leads to alterations in the sense of self-location. The combined effects of loss of parietal functions and enhanced DMN and limbic functions produce the core of what Newberg and colleagues have found in diverse mystical, meditative, and spiritual experiences, such as dissolution of a self–world boundary, with a decreased sense of being a “localized” self that leads to experiences of oneness, wholeness, unity, and transcendence. The loss of normal rPL inhibition has the effect of increasing activity in the DMN and limbic lobe, which is directly related to the experiential effects associated with a variety of ASC. These experiential effects include enhanced imagery and affective memory, vivid self-experience with altered self-location, self-boundary dissolution and unity experiences, intensified emotions, and increased introspection with heightened significance. Loss of rPL inhibition in the right-hemisphere DMN and limbic structures causes increased limbic intensity, resulting in heightened emotionality, emotional salience, and internal narrative self-talk, as well as increased meaningfulness.

Spiritual Experiences and States of the Self in the DMN

The diminution of ordinary self-functions to access spiritual experiences was originally proposed by d’Aquili and Newberg (1999) and illustrated more recently in a study (Fingelkurts, Fingelkurts, and Kallio-Tamminen 2021) that analyzed brain scans and verbal reports of spontaneous intrusions that occurred during meditative practices. These intrusions, as described in subsequent self-reports, had recurrent features that identify the basis of these experiences in relation to customary distinctions among self-types. Correspondences between the neurophysiological profiles manifested in operational synchrony analyses of EEG and the profiles revealed in self-reports identified three specific self-referential networks of the DMN. These self-referential networks are the intrusions into meditation, self-functions that are normally suspended during it, spontaneous manifestations that reflect intrinsic forms of the self. Based on these patterns, Fingelkurts, Fingelkurts, and Kallio-Tamminen (2021) propose three distinctive forms of experiential Selfhood, which they refer to as the I, Self, and Me. The following neurophenomenological descriptions are based on common patterns in self-reports and EEG reports (summarized from Winkelman 2024):

“Me”—Embodiment—representational-emotional agency. “Me” is also referred to as “minimal self,’’ “proto-self,” and “bodily self.” “Me” involves right posterior DMN, right temporal, parietal, and occipital lobes, which are the location of the mechanisms for interoceptive and exteroceptive sensory processing and emotional states and memories. The suspension of “Me” in meditation produces a loss of bodily perceptions, illustrating representation of the embodied self.

“I” —Reflection/narration—reflective agency. The “I” is involved in thinking about oneself, self-reflection, and reinterpretation of memories involved in episodic and semantic memory events, involving autobiographical storytelling. The “I” is localized in the left posterior DMN, the left temporal, parietal, and occipital lobes.

“Self”—First-person agency. “Self” provides the phenomenal sense of agency and the “phenomenal non-conceptual core in the act of knowing itself” (Fingelkurts, et al., 4). The “Self” involves anterior DMN regions, the left and right frontal lobes, and the frontal midline area.

Notably, all these forms of self are incompatible with meditative experiences, emerging as distractions from the intended focus of meditative practices. Consequently, whatever constitutes a spiritual self involves experiences that emerge following the suspension of these DMN-mediated forms of Selfhood, functions that reflect the innate functional operation of brain modules. This natural basis of the I, Self, and Me suggests that there should be other innately organized self-referential brain circuitry that provides the functional qualities and operational mechanisms that produce the phenomenal qualities of spiritual experiences.

This research (Fingelkurts, Fingelkurts, and Kallio-Tamminen 2021) also strongly suggests that it is the suspension of a range of self-related functions (aspects of Selfhood) that is a necessary precondition for spiritual experiences, and conversely, that the elicitation or operation of specific self-aspects interferes with spiritual experiences. These findings support a model of spiritual transcendence involving the suspension of ordinary neurological processes that support the sense of self.

Across diverse conceptualizations of the divine, there is a commonality in that achieving spiritual transcendence requires, in some sense, a reduction of the self. Experiences of spiritual transcendence result from conditions that impair the sense of self, with spiritual experiences occurring because the self functions that maintain a sense of separateness from others are compromised (D’Aquili and Newberg 1999).

Can it be that there is no self to the spiritual experience, or do remaining aspects of the embodied or narrative self have the experience of the spiritual? Or is the self manifested in spiritual experience not yet identified? The suspension of these specific self-processes as a requisite for spiritual experiences raises the question of what it is that experiences spiritual reality. If well-known forms of the self—embodied, narrative, “I,” “Me,” and “Self”—are suspended, this suggests that some other form(s) of the self is operative in the absence of parietal- and DMN-based forms of self.

Affective Core Self

This section proposes that the self at the basis of spiritual experiences involves the ACS—an evolutionarily ancient, subcortical, pre-reflective form of consciousness. This biological basis for spiritual experience is illustrated with a neurophenomenological model that shows how downregulation of embodied and narrative self-systems permits intensified ACS-driven interoceptive and affective processes that generate the characteristic phenomenology of spiritual feelings such as unity, bliss, peace, and transcendence.

Research on the trans-species biological aspects of the ACS (see Panksepp and Northoff 2009; Panksepp 2011a, 2011b) and its functional characteristics suggests a candidate for the spiritual self. This affective self provides a phenomenal and basic affective consciousness in relation to the environment. The ACS is a prelinguistic, preconceptual, and pre-reflective phenomenal consciousness that provides implicit and affective forms of self-related processing based in the subcortical midline structures (SCMS). The ACS is the evolutionarily oldest form of the self, manifesting even when other forms of the self are absent or in abeyance. The SCMS involves circuits found in reptiles and conserved in homologous forms in mammals and primates, serving as a basis for a “primary process” cognition shared by vertebrates (Panksepp 2011a). Humans and other animals share the SCMS, which provides the basis for the ACS, with functions to manage intrinsic affective states.

The principal brain structures of the ACS are located in medial (middle) brain regions and include notable DMN nodes such as the medial prefrontal cortex, anterior and posterior cingulate cortex, the cuneus and precuneus, as well as the brainstem, insula, hypothalamus, amygdala, hippocampus, and other limbic structures (Panksepp and Northoff 2009). These structures manage the evolutionary foundations of affectivity, mediating basic self-related processes (self-awareness, memory, affect), basic emotional responses, bodily sensations, motivation, autobiography, diverse social behaviors, and cognition.

The SCMS connections with the limbic brain regions that control homeostatic processes and visceral responses form the foundation of affective experience, manifesting in basic emotions and moods. Limbic regions provide meta-representations of sensory affects that differ from basic emotional affects due to the attribution of valuation through associative learning. These affective processes are expressed as social feelings in our relationships with the world and others, as well as in a myriad of influences on our varied senses of self, forming our basic traits and the patterns of our personality. These basic mammalian affective dynamics are central factors in consciousness and in producing the overall organization of the personality, providing the basis for all psychological functions (Alcaro, Carta, and Panksepp 2017). These ancient affective mechanisms provide the emotions and behaviors basic to our adaptations to environmental factors, influencing the habitual orientations of our moods and other affective habits.

The roles of the SCMS in emotional management may exceed the widely acclaimed capacities of the limbic system or emotional brain, organizing the basic affective neurodynamics and personality (Alcaro, Carta, and Panksepp 2017). These ancient brain regions manage instinctual and homeostatic processes, primary-process experiences, primordial emotions, and affective feelings (Alcaro, Carta, and Panksepp 2017, 9). The ACS reflects Carl Jung’s view of an instinctual affective form of Self consciousness based in affective relations with the material world.

The Affective Core Self as the Basis of Spiritual Experiences

Evidence that the ACS is the basis of many major features of spiritual and mystical experiences is based on the integration of inferences from many different sources. While there is no simple experiment to establish that the ACS is the basis of spiritual experience, evidence can be inferred from the homologies between basic ACS effects and the frequent characteristics of spiritual experiences. Further evidence would come from a neurological model of the mechanisms by which deliberate spiritual experiences (i.e., via meditation or similar practices) produce changes in the functions of ACS components, providing a paradigm for a neurophenomenological explanation of the brain mechanisms underlying spiritual experiences.

The ACS integrates information from diverse functions mediated by numerous hubs that form the network based in the subcortical connections of the brainstem, with an insula loop, the cingulate cortex, and the thalamus. This network provides the core interoceptive circuit that links sensory and interoceptive sources with emotional systems to generate raw feeling states and assessments of their significance.

The basic hubs of the ACS include the following:

The brainstem and hypothalamus provide homeostatic regulation of stress and soothing. Specifically, these core brain areas play a role in the production of primordial affective and motivational states (anxiety, pain, fear, and panic, as well as care and wellbeing). These subcortical emotional systems operate mostly outside of conscious control and attribute arousal, emotional meaning, and salience. These interoceptive emotional processes orient the affective valance of the self.

The insula is prominent in providing interoceptive awareness—the ability to perceive and interpret internal bodily sensations, such as hunger, thirst, heart rate, and emotions, in order to understand how the self is feeling. The insula interacts with cortical representation of the ACS via the prefrontal cortex and somatosensory cortices.

The anterior cingulate and cingulate cortex support motivational–affective processes linking affect and behavior.

Global integration is provided by the thalami, which integrate core feeling states and broadcast them across the cortex to allow bodily feelings to form the basis of a unified conscious self by integrating affective processes into conscious experience.

The role of the raw feelings of the ACS in spiritual experience is illustrated by the direct relationships between the basic functions of the primary affective systems and the central emotions of spirituality, which are reflected in feelings of awe, bliss, connectedness, peace, and reverence (Panksepp 2011a, 2011b). The role of the ACS in spiritual experiences is illustrated by these homologies between spiritual emotions and the functions of the primary affective systems. There are further homologies between the basic ACS functions and characteristics and the frequent manifestations of spiritual experiences. The ACS is rooted in bodily feelings, especially emotional warmth and feelings of caring, a calm interoceptive state of positive visceral conditions and emotional stasis, which fosters an overall general wellbeing. The ACS produces feelings often associated with the sacred, such as powerful affective experiences marked by sensations of warmth, energy, tingling, bliss, and joy, accompanied by physiological calm and a profound sense of aliveness and unity, with deep embodiment and emotional resonance. ACS functions can produce experiences that are homologous with specific forms of spiritual experiences, profound emotional peace, and ego dissolution, leading to experiences of radiance, mystical rapture, contemplative absorption, and self-loss in experiences of merging into a unity of consciousness with everything.

These core aspects of ACS and spiritual experiences reflect the functions of intensified interoceptive and primary emotional circuits with downregulation of body–boundary maps and threat systems that support an experience of an envelopment by and integration and unity into a meaningful embodied consciousness. Profound meaning is associated with the various functions of the ACS component systems, which provide strong interoceptive signals, promoting autonomic calm and positive emotional salience as well as safety, with a sense of embodied vitality and feelings of unity. ACS neural circuitry regions are all located in the lowest, most ancient parts of the brain. These all have key functions related to spirituality experiences, particularly the periaqueductal gray (PAG), a central node in mammalian attachment systems and a key part of the neural substrate of the ACS. The PAG contributes to the emotional core of spiritual and mystical experiences by producing raw primordial affective states such as bliss, compassion, emotional release, peace, safety, surrender, and tenderness (see Panksepp 2011b; Engström et al. 2010; Lutz et al. 2008; Solms 2021).

We hypothesize that the positive emotional intensity of spiritual states reflects the direct effects of this and other ACS circuits. For example, the activation of the ventral striatum, which engages reward and motivation salience, has been associated with awe, bliss, and feelings of devotion (Blood and Zatorre 2001; also see Keltner and Haidt 2003). The anterior insula, which integrates interoceptive signals with emotional awareness, has been connected with the experience of a “felt being” and feelings of mindfulness (Craig 2009; Farb et al. 2007). The thalamus, the brain’s central relay, integrative, and regulatory hub, is associated with feelings of mental clarity, unity, arousal, and general mystical states (Newberg, d’Aquili, and Rause 2001b). The amygdala, a central limbic hub with functions of attributing emotional meaning, autonomic regulation, and affiliative behavior, is associated with feelings of awe, surrender, and spiritual love (Yaden et al. 2017). In conjunction with the adjacent hippocampus, these limbic structures are also primarily involved in memory consolidation, which might help explain why mystical experiences have such a profound and long-lasting effect. Finally, the brainstem is involved with affective systems, the core self, and perhaps even proto-consciousness (Panksepp 2011a, 2011b; Solms 2021).

There are diverse spiritual effects that are homologous with the core characteristics and functions of the ACS. These homologies reflect the basis of ACS in the basic affective circuitry of the mammalian affective systems and the structure of the ACS in the integration of many hubs, themselves composed of diverse functions and effects that produce an integrative experience of positive wellbeing. While the ACS is always operative, even during sleep, it primarily comes to the forefront of consciousness and identity when the other self-systems are in abeyance. While experiences of the ACS can be accessed with introspective reflection and meditative states, their powerful engagement with personal consciousness primarily occurs with the downregulation of the parietal system and its embodied self, as well as the DMN and the narrative self. Then, the salience and interoceptive systems become dominant, and thalamic integration increases, providing the core dynamics of the ACS and associated elements of spiritual experiences.

Spirituality and Forms of Selfhood

Spiritual experiences have different effects on each of the major forms of Selfhood: the minimal, embodied, narrative, and affective selves. The minimal self is experienced as a pre-reflective awareness of self-as-subject with a first-person perspective on the environment, based on identification with the body and its point of view, and the feeling that one’s thoughts, sensations, and perceptions are their own. Spiritual experiences typically have little effect on the minimal self, with the sense of being a subject of experience remaining largely intact, although this sense sometimes may be diminished.

The embodied self, acting through the body, is an agent that can act in the world by controlling the body and engaging in actions through it. The effects of spirituality on Selfhood are most pronounced in the embodied self, leading to a loss of body boundaries and body schema, as well as loss of the sense of body location, ownership, and agency. The embodied self is the one most likely to be severely disturbed, and even disappear, during spiritual states. The embodied self is based on the integration of information from the sensorimotor network that is transmitted to the parietal cortex and the premotor circuits, PMC, and SMA. Consequently, the downregulation of the rPL would directly incapacitate the neural connections that are at the basis of the embodied self. The disruption of the parietal–premotor loop that produces the embodied self allows the emergence of spiritual states.

Spiritual experiences may also dramatically reduce the narrative and autobiographical selves, which are generally reduced during spiritual experiences. Diminution of the narrative self is illustrated by reduced rumination, a decrease in self-talk (internal dialogue), and a reduction in recall of autobiographical identity, leading to a decline in egoic preoccupations and the emergence of a “quiet mind” with immersion in the present moment. Loss of the embodied and narrative self leads to spiritual experiences.

As shown earlier, it is the ACS that shows a positive relationship to characteristics of spiritual experiences. The ACS functions express spiritual characteristics in features such as overwhelming emotional warmth and feelings of caring, as well as powerful affective experiences with sensations of calm and acceptance. Frequent spiritual features such as warmth, energy, tingling, bliss, joy, and physiological calm reflect ACS functions. The ACS functions produce experiences such as a powerful sense of aliveness and unity typical of spiritual experiences, as well as radiance, mystical rapture, contemplative absorption, and self-loss, providing deep emotional integration and unity of personal consciousness with the cosmos. The core functions of the ACS produce spiritual experiences through the intensification of interoceptive and primary emotional circuits during the downregulation of body-boundary processes and threat systems, which fosters deep embodiment and support, leading to an experience of emotional resonance with an enveloping “Other.” The spiritual aspects of the ACS are notably derived from the functions it produces rather than just because of the suspension of the functions provided by the rPL and DMN, illustrating the primordiality of the ACS in generating spiritual experiences.

Roles of the Right Hemisphere in Spiritual Experiences

This section shows that there is a close relationship between the ACS and the functions of the right hemisphere, reflecting right-hemisphere functions in the processing of emotional and interoceptive dynamics, affective tone, and emotional meaning. While the ACS is bilateral in the lower brain regions, at the level of cortical integration and expression, it is strongly lateralized in the right hemisphere, reflecting right-hemisphere dominance in emotional regulation, autonomic monitoring, and interoceptive and body awareness. The strong autonomic reactions and states of affective arousal associated with some spiritual experiences attest to their engagement of the autonomic nervous system, reflecting right-hemisphere capacities that integrate visceral processes and information (Newberg and Iversen 2003). Right-hemisphere structures play central roles in converting the ACS processing of affective and interoceptive states into subjective experience, emotional meaning, and conscious self-awareness, particularly through the right insula’s roles in interoception, subjective feelings, and emotional bodily awareness; right anterior cingulate regulation of affective arousal; rPL roles in embodiment and self-environment differentiation; and rTPJ integration of emotions and body schema (Craig 2009; LaVarco et al. 2022; Northoff and Bermpohl 2004; Schore 2021).

The relationships of many religious and spiritual experiences to right-hemisphere processes are detailed by Iain McGilchrist (2019a, 2019b). This research illustrates the need for a nuanced view that contrasts everyday religion— which is based in the right fronto-temporal networks and involves doctrines, beliefs, and convictions—with the ecstatic religious experience, which has affective and somatic dimensions and is more localized to the right temporal region. McGilchrist reviews extensive clinical and psychological research on hemispheric differences (which we cannot cite here for reasons of word count). McGilchrist concludes that although spiritual experiences involve both cerebral hemispheres, many aspects of these experiences reflect the distinctive cognitive and meaning-making processes of the right hemisphere.

Evolutionary adaptations have given us two distinctive attention systems: a left hemisphere, narrowly focused capacity to avoid predators and manipulate the environment, and a right-hemisphere system with a broad and open sustained vigilance to relate to the environment holistically, particularly to detect novel stimuli in the background or periphery. Right-hemisphere vigilance enhances awareness, allowing the person to see authentically, to perceive situations in a fresh light without the left hemisphere imposition of expectations based on past familiarity.

McGilchrist (2019a, 2019b) suggests that the right-hemisphere capacity to perceive broadly integrates understandings, sustains ambiguity, and provides nonlinguistic insights that enhance its ability to capture and express religious thought and experience. Right-hemisphere functions have direct implications for understanding religious experiences due to the nature of their approaches to broadly understanding reality. The right hemisphere is preferentially engaged in novel experiences and knowledge acquired by personal encounter, being especially receptive to things in both physical and imaginary worlds that are different from what is already known. The right hemisphere is more open to spiritual experiences and interpretations because it is receptive to the unknown and unexpected and possibilities beyond the realm of everyday experience. “Right hemisphere is more capable of apprehending the nature of the world and the possible role of the divine in it than is the left hemisphere” (McGilchrist 2019a, 328).

The right hemisphere can simultaneously entertain what appear to be conflicting positions, including ambiguity and paradoxes that encompass the whole truth about reality, which are often expressed as core realizations of mystical traditions. The right hemisphere is open to environmental elements that are not task relevant and outside of expectations through relationships established in an interconnected context that gives them meaning. The core of religious experience involves understandings that cannot be grasped by logical thought and language. The right hemisphere provides contextual understandings, such as those conveyed in metaphor, myth, and analogy, which offer insights into pragmatics (meaning in context). The right hemisphere has a greater capacity for empathy and understanding others’ perspectives and intentions (McGilchrist 2019a, 2019b).

The spiritual “Other” and sacred reality, qualitatively apart from everyday life, are more accessible to right-hemisphere processes that emphasize an open, relational awareness of that which is “beyond” our ordinary conceptual frameworks. The right hemisphere’s relational and contextual mode of perception parallels spiritual experiences of being embedded in a broader, more inclusive whole. This inclusivity is exemplified in spiritual experiences that present a lack of distinction between the self and its environment, instead fostering an intimate relationality with others, including spiritual entities. The spiritual encounter exemplifies the right-hemisphere mechanisms of knowing through acquaintance, with the encounter of the spiritual “other” exemplifying the operation of the right-hemisphere operations involving social cognition processing, especially theory of mind.

The right hemisphere engages knowledge and truth through mythos rather than the explicit left-hemisphere logos, providing a medium for accessing truths about the world that differ from the rationality of Logos, especially as expressed in myths and visual iconic symbols that offer both contextual meanings and higher universal truths. The ubiquitous nature of spiritual experiences as something ineffable, beyond words, illustrates the abandonment of the left-hemisphere linguistic frameworks, which are replaced with the right-hemisphere nonverbal semantic systems and meaning. The understanding provided by the right hemisphere can grasp metaphor and mythic images, the implicit meanings of music and poetry, and the expression in the behaviors of drama and ritual.

Right-hemisphere capacities produce a broad awareness that enables tolerance of ambiguity and holistic processing styles, facilitating spiritual experiences and their ineffable meanings, as well as a sense of unity and wholeness. Right-hemisphere processes produce an integration of embodiment with positive affective states and holistic information processing that reflects the phenomenological qualities of strong spiritual experiences. The right hemisphere supports an information processing style conducive to spiritual experiences, characterized by a felt sense of meaning and transcendence resulting from reduced boundaries between the self and others. Right-hemisphere processes also contribute to spiritual experiences by accommodating ambiguity, even contradiction, expressed in metaphors that facilitates an understanding of nonverbal, “numinous,” and “ineffable” qualities and meanings.

Conclusions: Spiritual Experiences as Evolution or Devolution?

The term “transcendence,” like “transpersonal,” implies going beyond the ego or the personal and moving beyond their normal functions. “When describing spiritual transcendence, it is often said that it is the ego, the self, or the individual identity that is being transcended to attain spiritual connection” (Johnstone and Cohen 2019, 40). While the concept of transcendence implies this movement beyond, we argue that the movement involved in bringing us to spiritual experiences is not beyond, as in outwards or upward. Instead, this movement is internal, a descent or retreat within cognitive and self-structures of the ACS and forms of auto-reference that preceded the ego and rational intellect.

The notion of the evolution of spiritual capacities is a complicated question because the brain areas that are downregulated in spiritual experiences, specifically the parietal lobes, include areas of the brain that have undergone significant increases relatively recently in human evolution. This is evidenced in their larger volume in humans, even in comparison to other species of the Homo lineage. This recent evolution is exemplified by the precuneus, a central hub located in the posterior parietal cortex, which is connected to both structural and functional brain networks. The precuneus is also part of the DMN and integrates information from diverse brain regions to contribute to high-level cognitive functions. The longitudinal expansion in the enlargement of the parietal region is a relatively recent development in human evolution, unique to Homo sapiens, occurring approximately 150,000–200,000 years ago (Bruner et al. 2017).

Since some functions of the parietal region appear suspended or even lost in spiritual experiences, we should question if the region is a specific source of spiritual experiences. For example, the suspension of recent evolutionary aspects of the brain, such as the parietal lobe’s precuneus during meditation (see Berkovich-Ohana, Glicksohn, and Goldstein 2020) illustrates that spiritual experiences do not derive from recently evolved human capacities. Instead, capacities for spiritual experience are masked by the more recently evolved neurological structures, with evolution changing how we relate to more basic aspects of experience that support spirituality. Humans’ spiritual experience may be viewed in this light as a reversion to an earlier capacity for experience rather than something unique to advanced human cognitive capacities and experiences.

This is illustrated in the connections between the affective self and spirituality, which Newberg (2024) examines in the common neurological foundations for ritual and sexuality. These connections are exploited by ritual to enhance experiences of attachment and sacredness through stimulating the brain’s bonding processes and contributing to experiences of unity. Ritually embedded sexual practices intensify ritual’s neurological effects on the limbic regions and parietal lobe functions that have central roles in producing the self and a sense of sacredness. Hormone release resulting from sexual orgasm and afterglow stimulates neural circuits that induce experiences of bonding, reduce self–other boundaries, and induce ASCs experienced as spiritual transformation.

Explaining the role of the parietal lobe in producing our sense of a separate identity and the role of the ACS in providing the content of spiritual experiences might be considered relatively “easy problems” of consciousness, given what we know about their specific functions (i.e., maintaining a sense of separation between our body and the environment and providing a range of positive mammalian affective qualities). Diminished parietal functions lead to experiences of greater unity and a sense of the inclusion of others within our identity. The ACS provides the positive emotional experiences of spiritual relations. This perspective provides a basis for a neurophenomenological understanding of some forms of spiritual experiences due to the loss of functions that provide a sense of separation of self from others. But more fundamental than these suspensions are the active roles of the ACS circuits in producing the experiential components of spiritual experiences.

Determining that specific brain regions are active (or inhibited) during certain “spiritual” experiences or ASC (or even psychedelic states) is a step in explaining their causal mechanisms. However, these correlations do not establish what causes the states. However, they may inform our explanations of the content and experiential qualities of these states. These explanations require the linkage of two arenas of observation: first-person experience and the associated functional brain dynamics. By linking experience to neuropsychology and identifying their homologies, we can begin a neurophenomenological science of spiritual experience. The identification here of the characteristics of spiritual experiences as homologous with the functions of the ACS and the right hemisphere is significant evidence for their deep interconnection. It extends the neurophenomenological perspectives on the self and spirituality.

These neurophenomenological relationships play an important role in elucidating the intersections between brain functions and spiritual consciousness, as well as their implications for the experience of the self. Spiritual experiences can emerge with the loss of DMN regulation and coherence, which allows consciousness to reconnect with the ancient ACS systems. The PAG anchors the raw feelings of bliss, compassion, and safety; the thalamus provides a sense of arousal and unity; the ventral striatum engages awe, devotion, reward, and motivational salience; the amygdala assigns positive emotional salience of love, surrender, and affiliation; and the insula integrates these primordial feelings into a sense of an integrated self with embodied presence.

Acknowledgments

The following sections include information sourced from ChatGPT: “Right Parietal Lobe Inhibition and Inhibition Loss in Spiritual Experiences” and “The Affective Core Self as the Basis of Spiritual Experiences,” as well as its following paragraph.

Competing Interests

The authors declare that they have no competing interests.