Common and distinct lateralised patterns of neural coupling during focused attention, open monitoring and loving kindness meditation

www.nature.com/scientificreports OPEN Common and distinct lateralised patterns of neural coupling during focused attention, open monitoring and loving kindness meditation Juliana Yordanova 1 ✉, Vasil Kolev 1, Federica Mauro 2, Valentina Nicolardi 2,3, Luca Simione 4, Lucia Calabrese2, Peter Malinowski 5 & Antonino Raffone 2,6 Meditation has been integrated into different therapeutic interventions. To inform the evidencebased selection of specific meditation types it is crucial to understand the neural processes associated with different meditation practices. Here we explore commonalities and differences in electroencephalographic oscillatory spatial synchronisation patterns across three important meditation types. Highly experienced meditators engaged in focused attention, open monitoring, and loving kindness meditation. Improving on previous research, our approach avoids comparisons between groups that limited previous findings, while ensuring that the meditation states are reliably established. Employing a novel measure of neural coupling – the imaginary part of EEG coherence – the study revealed that all meditation conditions displayed a common connectivity pattern that is characterised by increased connectivity of (a) broadly distributed delta networks, (b) left-hemispheric theta networks with a local integrating posterior focus, and (c) right-hemispheric alpha networks, with a local integrating parieto-occipital focus. Furthermore, each meditation state also expressed specific synchronisation patterns differentially recruiting left- or right-lateralised beta networks. These observations provide evidence that in addition to global patterns, frequency-specific inter-hemispheric asymmetry is one major feature of meditation, and that mental processes specific to each meditation type are also supported by lateralised networks from fast-frequency bands. Interest in meditation is burgeoning. Meditation and mindfulness exercises have been integrated into therapeutic interventions that target clinical conditions, including stress, chronic pain, depression and anxiety 1–5. Meditation-based programmes are also offered in non-clinical contexts, for example, workplaces, education, sports, and criminal justice systems6,7. While the majority of these programmes aim to enhance mindfulness skills, a growing number also foster compassion, including self-compassion. Typically, these programmes include a range of different meditation exercises. Although the reasons for including specific exercises in a programme often remain opaque, it is fair to assume that such choices were guided by the experience and preferences of the developers, rather than by scientific considerations. Arguably, in the early days of these intervention programmes, this approach was unavoidable because robust evidence about specific effects of distinct meditation types was unavailable. Furthermore, early meditation researchers sought insights about meditation practice in general, and in consequence did not offer a sufficiently nuanced picture of different meditation types. Meanwhile it has been acknowledged that a more fine-grained approach is needed. To put meditation and mindfulness interventions on more solid footing and encourage their evidence-based formulation and refinement, it is crucial to advance the understanding how different types of meditation work8–12. Besides considering meditations for their therapeutic effects, scientists are also interested in studying highly experienced meditators – meditation virtuosos – who have honed their mental skills over many years and are able to maintain different meditative states at will13–16. Investigating neural activity of these virtuosos during different 1 Institute of Neurobiology, Bulgarian Academy of Sciences, Sofia, Bulgaria. 2Department of Psychology, Sapienza University of Rome, Rome, Italy. 3Social and Cognitive Neurosciences Laboratory, IRCCS, Santa Lucia Foundation, Rome, Italy. 4Institute of Cognitive Sciences and Technologies, CNR, Rome, Italy. 5School of Psychology, Research Centre for Brain and Behaviour, Liverpool John Moores University (LJMU), Liverpool, UK. 6School of Buddhist Studies, Philosophy and Comparative Religions, Nalanda University, Rajgir, India. ✉e-mail: Scientific Reports | (2020) 10:7430 | https://doi.org/10.1038/s41598-020-64324-6 1 www.nature.com/scientificreports/ www.nature.com/scientificreports meditation states, offers a unique opportunity to understand what changes can be expected when people practice different types of meditation. Toward this end, the present study investigated the neural states associated with three prominent and distinct meditation types, often referred to as Focused Attention Meditation (FAM), Open Monitoring Meditation (OMM) and Loving Kindness Meditation (LKM)17–21. While FAM and OMM are integral components of standard mindfulness-based programmes, such as mindfulness-based stress reduction (MBSR)22,23, LKM is included in programmes such as Compassion Cultivation Training (CCT)24,25 or Cognitive-Based Compassion Training to Children (CBCT)26,27. The distinction between FAM and OMM was brought to prominence by Lutz et al.19, who drew parallels between Buddhist meditation traditions and secular interventions, such as MBSR. Subsequently, Vago and Silbersweig21 and Dahl et al.18 broadened this conceptual framework by including LKM practices, also referred to as “Ethical Enhancement Practices”21 or as “constructive meditations” that nurture pro-social qualities18. Focused Attention Meditation (FAM). FAM entails voluntary focusing attention on a chosen object in a sustained fashion. An important purpose of this meditation type is to enhance the cognitive skill of sustaining attention and to reduce emotional reactivity19,28. In principle, any object of the five senses as well as mental objects such as arising thoughts, feelings or even imagined visual objects can serve as reference point. As such, the exercise is not about an object per se, but about the ability to sustain focused attention. Within Buddhist contexts, the meditation type labelled here as FAM is often referred to by the Pali term Śamatha, typically translated as Calm Abiding meditation. Early stages of developing FAM or Śamatha are usually effortful, requiring meta-cognitive regulatory skills, such as recognising when the focus of attention is lost and the mind is distracted, disengaging attention from the source of distraction, and (re)orienting attention to the intended object19,29–31. Advanced practitioners are thought to require little – if any – effort to maintain focus, thus trivial regulatory skills will rarely need to be invoked19,32,33. Open monitoring meditation (OMM). While FAM maintains a specific object as reference point, during OMM attention is not explicitly object-focused. It rather involves the monitoring of the contents of experience and of mental processes in the present moment. With practice, the ability to obse (...truncated)