Most of the neuroscience research relevant to insight practice has so far focused on attention and meta-awareness processes associated with insight, rather than the states of intellectual and experiential insight as such. Researchers identified several regions in the brain based on the assumption that the state of open monitoring, which could be described as the attentional foundation of insight meditation, primarily involves vigilance and meta-awareness and also disengagement from distraction and shifting of attention back to the object of meditation (Lutz et al., 2008). In the context of monitoring bodily processes, these regions seem to consistently involve the anterior cingulate cortex, anterior insular cortex and secondary somatosensory cortex (e.g., Farb, Segal and Anderson, 2012). The anterior cingulate cortex supports voluntary attention control, disengagement from distractions and shifting of attention, whereas the anterior insula have been implicated in bodily awareness as well as awareness of emotional states and processes. Finally, the somatosensory cortex is activated during attention focus on the sensations in the body.
In addition to this research, some studies specifically investigated the differences in attention abilities between practices targeting focused attention and those developing open monitoring. This research, for example, showed that practitioners of open monitoring meditation are better able to detect unexpected stimuli than meditators mostly practicing focused meditation practice (Valentine and Sweet, 1999). This is perhaps not surprising given that differences in broad versus narrow focus of attention are inherent to open monitoring and focused attention, respectively, but these findings confirm that the distinction is reflected not only in meditation practice, but also in the actual performance of practitioner.
Another study of attention skills in insight meditators assessed changes before and after three months of Theravada insight retreat and found improvements in their efficiency of using attentional resources (Slagter et al., 2007). Specifically, the meditators were tested in an attention blink task which examined detection of simple stimuli such as letters or numbers during a very fast computerized presentation. The task is based on previous research which showed that within 500 milliseconds after detection of a target stimulus, we have a diminished capacity to detect another target. The three months of insight meditation retreat have been found to increase the detection rate of the second stimulus which suggests that the open monitoring capacity of meditators was enhanced. This pattern of findings was further supported by investigation of ERP responses to the targets which revealed less positive amplitudes to the first target of an ERP component (the P3b) sensitive to changes in attention resources. This decrease was interpreted as a lowered demand on attention resources, which enabled allocation of attention resources to the detection of the second target.
Aside from research on open monitoring, which can be considered a pre-requisite of insight practice, some studies aimed to link the changes in attention allocation to self-related processing. For example, one study compared brain responses of participants who completed an eight-week MBSR course with those new to meditation in a task that required participants to employ two different modes of self-referential processing (Farb et al., 2007). In both modes the participants were asked to respond to self-related adjectives such as ‘confident’, but in the narrative mode they were reflecting on the adjective in a story-like mode whereas in the experiential mode they were grounding their attention on the bodily sensations in the present moment. The findings revealed significant differences in brain activation in response to the two modes, which is not surprising given the differences in instructions and objects of focus. However, the MBSR group also showed stronger activation than the non-meditation group in areas such as the anterior cingulate cortex and secondary somatosensory cortex. While the differences were interpreted in terms of self-referential processing, a caution about such interpretation is warranted here given that the difference might simply be due to different attention focus and not relate directly to how the participants construed their sense of self.
The second group of studies aimed to investigate brain correlates of self-related processing by examining the default mode of brain function which assesses brain activity when participants are not instructed to do any particular task (other than resting or keeping their gaze fixated on a cross on the computer screen) (Raichle and Snyder, 2007). Previous research on the default mode suggests that off-task activity tends to activate a default mode network (DMN) of interconnected brain areas which has been linked to mind-wandering. Interestingly, some of the modes in the DMN, particularly those in the medial prefrontal cortex, have been directly linked to self-related processing – thinking about our own and others’ mental states. Therefore, investigation of activation in the DMN, and particularly areas linked to self-related processing in meditators could more closely reflect changes in existential insight arising from meditation practice.
Building on this assumption, one study compared DMN brain activation of meditators during three meditation types and resting and compared the pattern to brain activation in meditation novices (Brewer et al., 2011). The three meditation types were focused attention, loving kindness and choiceless awareness as an insight practice building on open monitoring. The findings revealed distinct differences between meditators and novices across the four conditions with meditators consistently showing a deactivation in areas of the DMN linked to mind-wandering (medial prefrontal cortex) and increased connectivity between brain areas linked to attention control and monitoring including the dorsal anterior cingu-late, posterior cingulate and dorsolateral prefrontal cortex.
Importantly, the pattern of DMN activation was very similar across the different meditation types, which the authors of the study interpreted as possibly reflecting changes in self-related processing (Brewer et al., 2011). However, this interpretation seems to assume that the three meditation types engage self-related processing equally whereas as discussed earlier in this chapter, it might be expected that their engagement of insight-related processing is differential. Specifically, focused meditation does not strongly engage insight-related self-reflective processing, whereas choiceless awareness targets it. Loving kindness could be expected to engage the self-related processes more than focused meditation but less than choiceless awareness practice. So an alternative interpretation of the similar findings across the practices might be that they reflect similar recruitment of attention resources associated with mindfulness and meta-awareness, since all three practices need to rely on these, rather than self-related processing.
Perhaps closer to the assessment of insight-related changes in the brain were recent studies that investigated different gradients of the self-boundaries (including differentiation between internal and external world and location in time and space) in experienced meditators and associated brain activation. The researchers first asked an experienced meditator to describe three different states of self-construal and then assessed whether these could be linked to dissociable brain patterns (Dor-Ziderman et al., 2016). When differences across the three states were obtained, the same instructions were applied in assessments of ten more advanced meditators to see if the same overarching pattern arises. The results across meditators revealed similar differences with increases in the right lateralized beta frequency generated by the temporo-parietal junction and the medial parietal cortex associated with more advanced levels of insight. These two brain regions have been previously linked to thinking about self and others and to self-transcending experiences, respectively. This study was perhaps the closest so far to actually linking self-related experiential changes (rather than changes in attention processing) to modulations of activity in the brain.
Research into the neurocognitive correlates of dream yoga practices could possibly become a fourth type of meditation research targeting insight-related changes. However, research on lucid dreaming has over the last three decades mostly focused on the possibility of inducing such a state and its applicability in the treatment of problems such as nightm
ares. No studies so far particularly targeted the investigation of self-related processing changes with lucid dreaming and derivative practices. The research on lucid dreaming has shown that this state naturally occurs and is also trainable. For example, one study reported that in a sample of 919 participants 51% of them reported having a lucid dream previously (Schredl and Erlacher, 2011). Women were more likely to report the experience of lucid dreaming, however, this might be related to a better ability to recollect the lucid dream rather than a difference in the frequency of lucid dreams between women and men.
A similar pattern was confirmed in a recent meta-analysis (cumulative) study looking at the reports across studies which investigated frequency of lucid dreaming occurrence without training. The study found that 55% of participants reported having a lucid dream at least once and 23% reported experiencing lucid dreams once or more per month (Saunders et al., 2016). Over 30 studies have also shown that it is possible for participants (between half and two-thirds of them) without any meditation background to develop lucid dreaming within a few weeks of practice (Stumbrys et al., 2012). While most studies only focused on the development of the ability to have lucid dreams, some studies also investigated the possibility of transforming dreams in the context of therapy for nightmares with a moderate success. None of these studies investigated the more advanced practices of traditional dream yoga, which examine the nature of self and reality.
A few psychophysiological studies have also documented brain correlates of lucid dreaming. For example, an early study on lucid dreaming showed that lucid dreaming is associated with the REM (rapid eye movement) phase of sleep (La Berge et al., 1981). This was inferred from responses provided by five participants who were trained in lucid dreaming and were also able to signal to the researchers that they were in a lucid dream by their eye movements. This approach was further replicated by other researchers, for example, one recent study trained six participants in lucid dreaming and investigated their brain activity during lucid dreaming – they signalled to the researchers that they were lucid in the dream by horizontal eye movements (Voss et al., 2009). Their brain activation during lucid dreaming was assessed using EEG and compared to brain activation when awake and during non-lucid dreaming (usual REM sleep). The findings revealed that lucid dreaming is associated with a pattern of brain activation that shares some features of being awake and some features of a non-lucid REM sleep. Specifically, lucid dreaming produced similar patterns of coherence in brain activity as being awake. Lucid dreaming was also associated with distinct activity in frontal and fronto-lateral areas which may reflect the metacognitive aspect of the state. The findings were, however, not specifically related to the self-construal.
Overall, current understanding of changes in brain function and structure with insight practices is quite limited. Most neuroscience studies investigated changes in attention processes contributing to states (open monitoring) supporting self-inquiry from which insight can arise. Other studies investigated changes in the default mode of brain function as a result of meditation which are often interpreted in terms of changes in self-referential processing but without direct links to phenomenological modulations in self-construal. So both research on attention and DMN changes related to insight currently falls short of investigating insight-related processing as such. A few studies attempted to map detailed phenomenological changes in the construal of self (changes in self-boundaries); more research of this type is needed, particularly if it is grounded in an overarching theory of phenomenological changes with insight progression. Finally, research on lucid dreaming seems to present interesting, and so far untapped, opportunities in investigating insight shifts. This is because previous studies documented that the state is trainable and associated with distinct psychophysiological patterns, yet they did not investigate trainability of participants in more advanced practices of dream yoga linked to the testing of dream reality and awake reality. Such studies could be conducted with experienced meditators skilled in dream yoga to assess brain correlates of advanced insight states.
Existential insight, self-regulation and existential well-being
We will now examine the insight practices from the perspective of a framework outlined in Chapter 1 which proposes that the effects of meditation practices can be investigated in terms of changes in the metacognitive self-regulatory capacity (MSRC) of the mind and shifts in modes of existential awareness (MEA) (Dorjee, 2016). In this framework, practices targeting the development of meditative insight would be primarily considered as aiming to induce shifts in the MEA. The MEA define our overarching sense of self and construal of reality, hence only insight practice that impact on our sense of self-construal would be expected to lead to changes in MEA. For this reason, the term ‘existential insight’ referring more closely to the existential construal of self and reality seems appropriate in describing practices and states of this type. In addition, the term ‘insight’ has been applied in the psychological literature for a long time in reference to sudden shifts of understanding which is not related to the construal of self or reality in the contemplative sense, so it seems appropriate to distinguish it from existential insight.
The link between existential insight and MEA means that for a state to be described as existential insight it needs to be relevant to changes in the sense of self or reality. Based on this assumption, object-oriented insight (Dahl, Lutz and Davidson, 2015) would perhaps not be considered a type of existential insight, unless it can be shown how such object-oriented insight impacts on the self-construal. This further highlights that decentring, which was included in the category of object-oriented insight (see the first section of this chapter), is probably better classified as one of the beginning stages of subject-oriented insight. This is because decentring enables the participants to experience a MEA characterized by partial dis-identification with thoughts, sensations and feelings, which modifies the sense of self. This MEA could be considered one of the initial shifts in MEA resulting from meditation practice.
Starting with initial experience of decentring and up to the highest levels of existential insight in pristine awareness, long-term meditation practice can be associated with a range of progressively more advanced shifts in MEA. These shifts can also be described in terms of increasingly deeper access in terms of the three layers of consciousness: ordinary consciousness, substrate consciousness and the nature of mind (pristine awareness). Accordingly, the main shifts in MEA involve, as the first major step, existential insight into the construed, impermanent and changeable nature of our thoughts, sensations and feelings arising during progression from the ordinary mind into the substrate consciousness. This is followed by increasingly advanced shifts in MEA targeting the deconstruction of the conditioned notions of self at the level of substrate consciousness. This process culminates in a major shift from the ground of substrate consciousness into the level of the nature of mind when the construed sense of self dissolves. At the level of the nature of mind the final existential insight goes beyond this realization by experiential dissolution of the distinctions between the self and the other (the observer and the observed) into the state of cognizant non-duality experienced in pristine awareness. According to some Buddhist teachers, even within this state, gradients of extremely advanced non-conceptual states characterized by different degrees of existential knowledge can be distinguished (Gyaltrul and Wallace, 1998).
While existential insight meditation practices do not target the MSRC, shifts in MEA can only arise when the processes of the MSRC have been sufficiently refined. This is achieved mostly through practices training mindfulness and meta-awareness (Shamatha, see Chapter 3), practices cultivating emotional qualities such as compassion (e.g., the four immeasurables, see Chapter 4) and practices modifying conceptual processing including contemplations on existential topics (but also Shamatha practices and practices working with emotions). The visualization-based practices (see Chapter 5) seem to work across the range of the three main components of t
he MSRC (attention and meta-awareness emotion regulation and conceptual processing) and also cultivate existential insight. The refined MSRC processes create the conditions for shifts in MEA through the stabilization of attention focus, enabling effortless observation of deeper layers of consciousness. This also requires refined meta-awareness as a core aspect of the MSRC, so that the meditator can notice distraction and patterns of mental processes. Development of wholesome emotional qualities stabilizes the emotional processes of the mind further and also reduces fixations on distinctions between self and other through development of equanimity in cultivating loving kindness and compassion. Visualization practices train attention and meta-awareness, cultivate wholesome emotions and at the same encourage existential insight by developing experiential understanding of the illusory nature of mind and reality. They also support connection with advanced states of existential awareness through exemplification in the form of deity mind. Building on this overall stabilization and refinement of the mind, existential insight practices can further target inquiry towards the most-advanced experiential realization of the nature of mind and reality.
In the proposed framework, the enhancement of the MSRC as a prerequisite for practices cultivating existential insight together with increasingly more advanced shifts in the MEA is associated with improvements in overall well-being. This is because self-regulation and existential well-being are the core pillars of human well-being and existential insight practices further improve existential well-being (which can be cultivated in other practices only to a limited extent). This suggests that approaches aiming to prevent illness, enhance well-being or treat illness need to target enhancements in both self-regulation and existential well-being. Long-term meditation training initially mostly develops the self-regulatory skills and to a limited extent existential well-being. More advanced meditation training particularly targets improvements in existential well-being, via existential insight practices, after self-regulatory skills have been sufficiently enhanced.
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