Neuroscience and Psychology of Meditation in Everyday Life
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The studies we have discussed show that meditation practice can lead to both state and trait changes in the mind and brain, but meditation-related traits are present even without any meditation training. Mindfulness is a good example of this. We will discuss definitions of mindfulness in detail in the next chapter; here it will suffice to say that mindfulness can be described as the ability to notice our emotions, thoughts and sensations in a non-reactive way and regulate our attention to these. While research studies show (see examples above in this section) that mindfulness is a modifiable state as well as a trait, they also suggest that mindfulness is a disposition all of us have to some degree regardless of whether we have been engaging in formal mindfulness practice. In other words, some people are naturally more mindful than others even without any mindfulness training.
In research, assessments of the mindfulness disposition have been used in examining brain activation which can be associated with this trait. For example, in a neuroscience study with participants without previous meditation training researchers investigated the possible relationship between mindfulness disposition and processing of emotions (Creswell et al., 2007). Participants were asked to view faces with angry or sad emotional expressions and respond to them either by labelling the emotion depicted or the gender of the face in the picture. The findings revealed that in the emotion-labelling task participants with higher mindfulness disposition (naturally more mindful) showed stronger activation in prefrontal brain areas (particularly medial prefrontal cortex) associated with cognitive control and monitoring of thoughts and emotions. More mindful participants also showed decreases in the activation of the amygdalae linked to the stress response. Interestingly, there was a negative relationship between the activation in the prefrontal areas and the amygdalae – the higher the activity in the prefrontal cortex the lower the activity in the amygdalae. This indicates a possible neural mechanism of emotion regulation with the prefrontal areas downregulating the activity in the amygdalae during affective labelling as a possible mindful emotion regulation strategy. However, the mindfulness disposition wasn’t related to differences in brain activity in the gender-labelling task. These findings provided interesting insights into how mindfulness disposition could be involved in regulation of emotions, with other studies applying the same principles in investigating links between the mindfulness disposition and attention etc.
Research on dispositional mindfulness (and other meditation-related traits), however, also has some drawbacks. For instance, it is possible that findings in the study we have just discussed (Creswell et al., 2007) were influenced by other participant abilities the researchers did not assess such as general attention abilities or better emotion regulation. This could be the case since higher mindfulness is associated with better attention abilities (Malinowski, 2013). So in a way it is a case of a ‘chicken vs egg’ problem with dispositional attention and dispositional mindfulness – we cannot determine whether better attention naturally leads to more mindfulness or if it is the other way around. This is a general shortcoming of studies relying on associations between trait dispositions and brain activity – we cannot interpret their findings in a conclusive way because it is not possible to ascertain whether they were purely due to the disposition or other factors. Studies which involve assessments before and after meditation training are able to provide stronger evidence of changes resulting from meditation because we have a starting point of assessing participants’ brain activity and therefore changes observed after the training are attributable to meditation as the only factor which changed during the training time. This can be further ascertained by inclusion of a control group in a study to make sure changes observed after meditation training are not due to other factors such as different time of the year, aging, practice with the assessment tasks etc.
Interestingly, changes in states as well as traits can interact with the dispositions we have towards meditation. For example, earlier in this section we have discussed fMRI research findings from participants without any previous experience of meditation who showed state differences in brain activation when they were engaging in breath-focus meditation and in unfocused attention state (Dickenson et al., 2012). In the same study the researchers found that those participants who were naturally more mindful (higher mindfulness disposition) also showed stronger activation in brain areas associated with attention control during the brief breath-focus meditation. This suggests that disposition to mindfulness (keeping in mind the drawbacks of dispositional research discussed in the previous paragraph) may influence how readily we engage with actual mindfulness practice and associated brain changes.
Indeed, an MBSR study provided preliminary support for this suggestion in an investigation of possible links between baseline levels of trait mindfulness and well-being gains from participation in an MBSR course (Shapiro et al., 2011). The researchers found that participants who were naturally more mindful at the start of the training showed larger improvements in well-being than those with lower mindfulness disposition. These differences in gains amongst the initially more and less mindful participants were present even when assessed one year after the MBSR training was completed. However, initial research with children points to the reverse effect. In a study with primary school children (7–9-year-olds) those with lower levels of executive control to start with showed the largest improvements in executive control (regulation of behaviour, meta-cognition, etc.) after mindfulness training (Flook et al., 2010). Even though the researchers did not assess mindfulness levels directly, other research suggested that executive control performance and mindfulness are positively linked (Teper, Segal and Inzlicht, 2013). These findings need to be interpreted with caution, since both the study by Shapiro et al. (2011) and Flook et al. (2010) had small sample sizes and some aspects of their statistical analyses were not very strong, but this research highlighted the importance of investigating links between mindfulness disposition and gains from mindfulness training. Further research is needed to elucidate these associations.
Overall, the available evidence suggests that meditation can lead to both temporary changes in mind and brain states and to longer-term shifts in personality traits, cognitive functioning and brain structure. Initial findings also indicate that natural dispositions towards meditation practice may impact on the beneficial effects participants experience from meditation training. These suggestions, however, should be considered with caution because findings of studies relying on questionnaire measures of mindfulness are subject to many shortcomings such as differences in interpretations of questions and ability to reflect accurately on our mental states and traits (Grossman, 2011). There is also an ongoing debate in the field about how to best measure meditation-specific states, traits and dispositions such as mindfulness to avoid some of these limitations with one possibility being reaction-time assessments instead of questionnaires (Levinson et al., 2013). These debates are far from coming to an overarching consensus at the moment. Nevertheless, the distinctions between state and trait effects of mindfulness have practical implications for our considerations of long-term effects of meditation in everyday life, both within and outside of formal meditation sessions, and we will build on these distinctions in our discussions in the following chapters.
The quantity and quality of meditation practice
The questions about state and trait effects of meditation are closely related to how often (quantity) and how proficiently (quality) we are engaging in meditation. The quantity of meditation practice seems to be more straightforward to assess – we simply need to keep track of the minutes and hours we spend in meditation practice every day, every week etc. However, keeping track of meditation practice becomes more complicated if we broaden the amount of practice to meditation on the go – informal practice we may engage in throughout the day (we will discuss the differences between formal and informal meditation practice in more detail in the next section). But why should we try to evaluate the amount of practice in the first place? The
reasoning here is that the more we practice, the more we improve in our ability to meditate, which we would expect to translate into both state and trait changes. The trait changes could then have more profound impact on our health and well-being both within and outside of formal meditation practice.
Indeed, there is research, even though limited in numbers and scope, suggesting that more hours spent in meditation practice result in more beneficial effects on health and well-being. For example, a study which investigated the relationship between formal meditation practice and outcomes of MBSR training found that those participants who spent more time in formal meditation at home also showed larger increases in well-being from before to after the MBSR course (Carmody and Baer, 2008). Similarly, a study with military personnel who were experiencing pre-deployment stress found that those who spent more time in home meditation practice (as part of an MBSR course) showed larger reductions in negative affect and increases in positive affect (Jha et al., 2010). The study also found that those with more hours of practice outside of the MBSR classes showed increases in working memory capacity. This is an important finding given that stress is associated with a reduction in working memory capacity and military personnel from this study with less hours of practice did not show the protective effects of mindfulness on working memory (they showed a decline in working memory).
Amount of meditation practice has also been associated with differences in brain changes resulting from meditation. For instance, one fMRI study investigated links between the amount of long-term meditation practice and connectivity between brain areas which support attention control (Hasenkamp and Barsalou, 2012). The connectivity patterns examined were particularly relevant to disengagement from random mind-wandering as an off-task unfocused activity. The findings reported stronger connectivity of the attention networks in meditators with more hours of meditation, suggesting that more meditation practice is associated with more pronounced neural plasticity changes underlying attention control.
However, the relationship between the amount of meditation practice and associated changes in the brain is not always linear – more meditation practice does not always mean more brain activity (or less brain activity if the activity is associated with health detrimental effects). Indeed, a study which compared meditation beginners with experienced meditation with less and more hours of meditation practice found a non-linear pattern of brain activation differences amongst the groups (Brefczynski-Lewis et al., 2007). Experienced meditators in this study were practitioners in the Tibetan Buddhist tradition divided into two subgroups: the ‘less’ experienced subgroup with 19,000 hours of meditation practice on average and the ‘more’ experienced subgroup with the average of 44,000 hours of meditation. The meditation beginners received written instructions in meditation and were asked to practice meditation 1 hour per day for a week. Both beginners and experienced meditators were asked to practice concentrative meditation during the evaluations. The fMRI assessments of differences in brain activation between the beginners, less experienced and more experienced meditators pointed to an interesting non-linear pattern of differences in brain activation during the concentrative meditation. As expected, beginners showed less activation in brain areas related to sustained attention than experienced meditators with less hours of practice. However, experienced meditators with more hours of practice had less activation in the same brain areas linked to sustained attention than experienced meditators with less hours of practice. In fact, the pattern of brain activation in the experienced meditators with more hours of practice was similar to the pattern of meditation beginners. While the diminished brain activity in beginners may have been linked to them being less able to recruit attention control areas of the brain during meditation, similar brain activity pattern in the meditators with more hours of practice likely reflects effortless engagement in sustained attention which does not require strong recruitment of attention networks.
Coming back to differences in effects with quantity of secular meditation training, interestingly, the length of formal in-class meditation training does not seem to be strongly associated with positive participant outcomes, unlike home meditation practice. Indeed, preliminary research did not find a significant relationship between the amount of formal in-class training in the MBSR and mindfulness-based cognitive therapy (MBCT) and participant gains in terms of health and well-being (Carmody and Baer, 2009). The standard training in MBSR involves 2.5-hour weekly sessions delivered over eight weeks (2-hour weekly sessions in MBCT). The study looked at published research with the standard or shorter than standard duration of weekly sessions (or less than the usual eight weekly sessions) and related the overall duration of the training to the size of the effects in terms of participant improvements. The lack of a quantity of training effects in the findings from this study suggests that shorter training may be equally effective in improving participants’ health and well-being and also highlights the importance of home practice which does seem to relate to participant outcomes. A contributing factor here might be the quality of engagement with the meditation practice in shorter sessions, a factor which we will consider now.
Research on quality of meditation is very limited, but initial findings suggest that qualities such as drowsiness during meditation can impact on measurable outcomes of the practice. Specifically, a study with experienced Vipassana meditators investigated brain patterns associated with distractibility by comparing ERP patterns during a focused meditation session and during a period of neutral thinking. Participants’ brain responses to a simple series of tones were recorded during both meditation and thinking. White noise sounds were randomly embedded in the sequences of the tones to measure automatic reactivity of attention to distractors. The ERP findings showed that meditators’ brains responded much less to the distractor sounds during meditation in comparison to the thinking period. Interestingly, meditators were also asked to rate how drowsy they felt when they were meditating right after completion of the session. The rates of drowsiness were then related to the modulation of the ERP index measuring brain responses to the distractor white noise. The results showed that only meditators who did not report feeling drowsy showed lower automatic response to the distractor sounds. In other words, they were less distracted during their meditation session. This suggests that absence of drowsiness as an indicator of better quality of meditation is linked to measurable changes in brain indexes of distractibility.
Interestingly, it has been recently suggested that quality of attention during meditation could be used as an assessment of mindfulness and is directly related to the health and well-being we experience. In one study (Burg and Michalak, 2011) participants (majority of them without prior training in meditation) were asked to observe their breath during short time periods of 20 to 80 seconds. While engaging in this meditation practice the participants pressed the left button whenever they noticed being on the breath and the right button when they lost track of their breath. They were also asked to fill in questionnaires assessing their depression and rumination levels. The findings of the study showed that participants who were better able to stay focused on their breath also reported lower levels of rumination and anxiety. Better focus on the task was also associated with higher levels of acceptance and acting with awareness as dimensions of mindfulness, suggesting a link between some aspects of questionnaire assessments of mindfulness.
A similar principle was assessed in a study (Levinson et al., 2013) with a larger sample of participants. They were asked to press count their breaths and press a button for each outbreath from the first breath to the eighth breath and a different button for the ninth breath, then start again from one. This assessed how well participants were able to stay focused on their breath as a possible measure of mindfulness. In addition, the researchers asked the participants approximately every 90 seconds about their meta-awareness – how aware they were of where their attention was. The findings indicated that those who performed better on the breath-counting task also repo
rted higher mindfulness on a questionnaire assessment. In addition, meditators showed higher breath-counting accuracy than meditation novices, suggesting that the task was sensitive to meditation experience.
Interestingly, these assessments of mindfulness seem to tap into some aspects of attention qualities described in the Buddhist context where the cultivation of attention skills in meditation is typically outlined in terms of relaxation, stability and clarity as basic qualities of attention (Wallace, 2006). Relaxation is characterized as a balanced way of paying attention without tension or too much laxity. Stability relates to the ability to sustain attention on an object of meditation, such as breath or a sacred statue, with continuity and without losing the focus on the object of meditation. Clarity of attention in meditation describes the vividness and detail of attention focus. Buddhist teachings on calm abiding (Shamatha) build on the distinctions between these qualities of attention and present a comprehensive account of changes in relaxation, stability and vividness of attention with progression in meditation training.