‘Focus on your breaths.’ ‘Inhale, exhale’ ‘Acknowledge the distracting thoughts coming into your mind and let them go.’ Sound familiar? What is it asking you to do here? Of course, it is asking you to let go of the distracting thoughts that are bombarding your mind and focus on the part of us that we take for granted - breathing. Harder said than done! How nice would it be to be able to control your attention without getting distracted? How productive would your day be? In fact, mindfulness meditation doesn’t just require our focus, it seems to improve our focus. Don’t believe me? Read on. Before we go into the nitty gritty details of it, it is important to be clear in our minds what meditation is. Meditation can be defined as a form of mental training which aims to improve a number of core psychological capacities, such as concentration and emotional regulation<1>. The term meditation encompasses a number of practices including mindful meditation, mantra meditation, yoga, tai chi and chi gong <1>. Of course, what we will concentrate on here is the mindfulness meditation. Specifically, is mindfulness medication able to help us gain focus and maintain attention? It is worth mentioning that the scientific research in meditation has only just begun. Think of it as a one-day-old baby who has just started gulping in the air of science. Many researchers in this area are avid meditators themselves. One may argue that they may be rather biased for something positive to come out of the studies. It is hard to say, especially considering that most study findings are yet to be successfully replicated. However, it is still an intriguing field to delve into. A fascinating systematic review published in 2015 in the prestigious Nature Reviews looked at 21 studies in the prior decade<1>. The studies are mainly cross-sectional, in other words, comparing data from experienced meditators to non-meditator at one given time. This type of study does not take into account of pre-existing differences amongst the two groups. However, there are some studies which are prospective, in which researchers followed the same group of people over a period of time, looking for differences between people who do not end up meditating and those who do. This type of study enables better elimination of possible confounding factors which might influence the outcomes. To grasp the neuroscience of mindfulness meditation, we need to first think about the cognitive processes involved in meditation. Attention is a word which springs to mind with mindfulness meditation. If you think about it, the whole idea of meditation and mindfulness is to focus your attention on one specific point, be it your breathing or the feeling of your heart beats. Therefore, our first step is to understand the science behind attention.
The current research on attention is thoroughly fascinating. It has been established that attention is not a single process, rather a complex cognitive process which involves three main components: alerting (a sense of vigilance and readiness for the reception of stimuli, in other words, staying alert), orienting (the capability to shift one’s focus from one stimuli to the next) and conflict monitoring (to discern the target of your focus from all the distracting stimuli around it). Let us take a second here to think about these domains in real life practice. Think back to the last time you were sitting in front of your office desk trying your best to get through all the tasks on your To-Do list. You need the ability of alerting to staying awake and alert, so you are not asleep when your boss walks in. In order to sift through different tasks, you need orienting to constantly shift your focus onto different tasks, which may be located in different folders on your desktop. Lastly, you need the ability of conflict monitoring to not get distracted by the voices and commotions around you in the office. Now you realise how important the domains of attention are in your daily life, right? So how do we test for these three domains? The most popular test is the attention network test. Here is a link for you to see how the test works. Essentially, it is a predominantly computer-based tracking game with specific components and variations to quantify one’s ability in each of these three domains. Using this test, researchers are able to identify the areas of the brain that are most active when each of these domains is being tested. How does this translate to the effect of meditation practice on enhancing attention? A lot of studies used attention network test and other similar tests as a tool to examine the effect of meditation on these crucial cognitive domains. I will go through the research looking at each of these domains and how they are affected by meditation. Effects on conflict monitoring A number of studies have suggested that mindfulness meditation enhances the level of conflict monitoring - our ability to bat away the distractions and focus our mind on what’s important. For instance, one study that follow people up for a period of time showed that only 5 days (20 min per day) of integrative body–mind training (IBMT) led to improved conflict monitoring <3>. Similar findings are found with 3 months of meditation <4> and in people who are more experienced meditators <5>. . Effects on alerting and orienting It seems that the capacity to remain alert and orienting to different stimuli may only be improved upon long-term meditation. Studies found that experienced meditators had enhanced alertness. For instance, one study found that Shamantha mindfulness training increases the ability to stay alert over time as well as orienting <6>. However, an 8-week mindfulness-based stress reduction did not seem to improve alertness, only orienting<7>. You may wonder how these improvements in attentional domains come about? Is mindfulness meditation making a lasting change to the brain areas that controls attention? In the last decade, many neuroimaging studies have attempted to answer these questions mainly using magnetic resonance imaging (MRI). Functional MRI is a specialised type of MRI that measures increased metabolic activity to particular areas of the brain in response to certain stimuli or activity. Several functional and structural MRI studies have linked the effects of mindfulness training to one area of the brain called the anterior cingulate gyrus (ACC). Interestingly and perhaps not surprisingly, ACC is a well-established area involved in conflict monitoring. Cross-sectional studies have reported enhanced activation of the brain activity in the ACC amongst experienced meditators compared to people who never meditated before <8>. As the level of meditation expertise progresses, the activity in this region may paradoxically decrease <9>.. This is plausible as it may requires increasingly less effort, i.e. metabolic activity in the brain, to achieve the same level of conflict monitoring. Other areas such as the dorsolateral prefrontal cortex, commonly activated in performing executive tasks, and parietal region, our brain’s spatial orientation centre, have also been found to have enhanced activity in meditators<1>. Despite the evidence we have discussed so far, the findings are nowhere near conclusive. The studies have shown that meditators may have better level of the performance in the three attention domains and it seems that meditation is indeed associated with changes in the brain activities in areas that controls attention. However, what is lacking in research is how the improvement in performance is related to the changes in brain activities. In other words, does meditation cause changes in the brain which directly causes the enhanced performance in attention tasks? We need more research linking the two. For now, carry on and keep meditating! References <1> Tang et al. The neuroscience of mindfulness meditation. 2015. Nature Reviews. doi:10.1038/nrn3916 <2> Fox, K. C. et al. Is meditation associated with altered brain structure? A systematic review and meta-analysis of morphometric neuroimaging in meditation practitioners. Neurosci. Biobehav. Rev. 43, 48–73 (2014). A review of structural alterations in the brain associated with meditation. <3> Tang, Y. Y. et al. Short-term meditation training improves attention and self-regulation. Proc. Natl Acad. Sci. USA 104, 17152–17156 (2007). <4> Slagter, H. A. et al. Mental training affects distribution of limited brain resources. PLoS Biol. 5, e138 (2007). <5>Van den Hurk, P. A., Giommi, F., Gielen, S. C., Speckens, A. E. M. & Barendregt, H. P. Greater efficiency in attentional processing related to mindfulness meditation. Q. J. Exp. Psychol. (Hove) 63, 1168–1180 (2010) <6> MacLean, K. A. et al. Intensive meditation training improves perceptual discrimination and sustained attention. Psychol Sci, 21, 829–839 (2010). <7> MacCoon, D. G., MacLean, K. A., Davidson, R. J., Saron, C. D. & Lutz, A. No sustained attention differences in a longitudinal randomized trial comparing mindfulness based stress reduction versus active control. PLoS ONE 9, e97551 (2014). <8> Hölzel, B. K. et al. Differential engagement of anterior cingulate and adjacent medial frontal cortex in adept meditators and non-meditators. Neurosci. Lett. 421, 16–21 (2007). <9> Brefczynski-Lewis, J. A., Lutz, A., Schaefer, H. S., Levinson, D. B. & Davidson, R. J. Neural correlates of attentional expertise in long-term meditation practitioners. Proc. Natl Acad. Sci. USA 104, 11483–11488 (2007).
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