The Neuroscience of Meditation

Understanding Individual Differences

Yi-Yuan Tang, Rongxiang Tang

• Publisher: Academic Press
• Year: 2020
• ISBN:
  9780128182673
• Topic: Ciencias biológicas
• Subtopic: Neurociencia

The Neuroscience of Meditation: Understanding Individual Differences explores the individual differences in learning and practicing meditation, while also providing insights on how to learn and practice effectively. The book comprehensively covers the research in brain areas and networks that mediate the positive effects of meditation upon physical and mental health. Though it examines how people differ in how they learn and practice meditation, it underscores how underlying mechanisms differ in learning and practicing meditation and how they remain unclear to researchers. This book addresses the research gap and explores the brain science behind meditation.

• Examines the biological mechanisms that give rise to individual differences
• Incorporates brain imaging and physiological recordings for further measurement of individual differences
• Covers the genetic association between meditation learning and practice
• Explores how meditation changes over the lifespan—from children to seniors

Chapter 1

Theoretical frameworks of individual differences in interventions

Abstract

Individual differences in response to medical treatment and procedures are widely recognized by physicians and healthcare professionals. Even for psychological interventions offered within clinical contexts, individual variability can often be observed by therapists. Notably, not only are such differences visible at a one-on-one patient to therapist level, but also are present in group-based interventions where multiple individuals receive the same standardized curriculum taught by the same instructor. To facilitate the understanding of empirical studies of individual differences in psychological interventions, especially in meditation (Chapters 1–10), we seek to first establish the theoretical background and rationale for conducting individual differences research in meditation. Although meditation is not only regarded as a psychological intervention for clinical purposes, it is useful to discuss the perspective of individual differences from a clinical standpoint as individual differences are heavily emphasized within clinical contexts. Therefore the goal of this chapter is to: (1) discuss important conceptual frameworks of individual variability relevant for psychological interventions; and (2) identify potential individual attributes pertinent to the observed differences in intervention responsiveness across individuals.

Keywords

Meditation; individual differences; patient-centered care; aptitude-treatment interaction; precision medicine; personalized medicine

Individual differences are ubiquitous in everyday life, but are often overlooked when medication, intervention, or treatment is deemed suitable and appropriate for the general population. As such, individual needs and preferences are often overlooked by the individuals themselves and those providing the treatment. Indeed, when we operate under the assumption that an intervention works for everyone, we unintentionally fall into the trap of thinking a universal panacea exists for the targeted symptoms and would work the same for different individuals. In reality, people are far more complex and diverse, which can lead to differential responsiveness to the same treatment approach, subsequently affecting the extent of the treatment’s effects on the targeted outcomes. For instance, even for medication (e.g., penicillin) that commonly work for most of the population, exceptions such as drug allergy and nonresponsiveness occur in a small percentage of people. When it comes to psychological interventions we are even more likely to not think about whether our unique preferences and characteristics would make us less suitable for, and less responsive to, a specific intervention. Aside from clinical applications, the presence of individual differences can also be found in scientific investigations. However, individual variability is often not carefully considered when it comes to empirical studies of psychological interventions, as most studies only examine group-level effects of the intervention on specific outcomes and assume it is equally effective and suitable for everyone within the studied group.

As one kind of group-based psychological interventions for improving psychological symptoms and health, meditation has been actively applied and practiced within clinical settings. It is also being widely practiced as a mental training or lifestyle intervention by people from the healthy population who seek to enhance psychological well-being and cognitive function. Similar to other kinds of psychological interventions, the benefits of meditation have been mostly generalized to the population level in prior research, yet mixed outcomes are increasingly being reported by studies (MacCoon et al., 2012; MacCoon, MacLean, Davidson, Saron, & Lutz, 2014; Rosenkranz et al., 2013). For instance, the positive effects on sustained attention were not significant when comparing the mindfulness-based stress reduction (MBSR) (a meditation-based intervention) with an active control intervention (MacCoon et al., 2012). Likewise, the MBSR program does not seem to be more effective than active control intervention in reducing psychological distress and physiological symptoms (Rosenkranz et al., 2013). Typically, when examining the effects of an intervention, a randomized controlled trial design with an active control intervention is used for the experiment so that we are able to compare our intervention effects against that of a similar alternative in order to minimize potential confounding variables. The benefits in enhancing psychological well-being and attention were not replicated as in other studies that also utilized active control interventions for comparison. Looking at the effect sizes of meditation studies, several meta-analyses of different studies on meditation benefits have shown that the degree of improvement in psychological health and aspects of cognitive function following meditation have varied from small to moderate (Chiesa, Calati, & Serretti, 2011; Gu, Strauss, Bond, & Cavanagh, 2015), suggesting that there is a considerable amount of variability across studies.

These mixed findings point to two possible explanations: (1) meditation does not have an effect on individual well-being and cognition (or only has a subtle effect); and (2) meditation does not induce the same level of benefits in every individual and the extent of improvement may be affected by preexisting individual differences. The first explanation has been proposed by skeptics, who think that the observed positive effects of meditation could either be spurious findings or an exaggeration of subtle benefits resulting from meditation practices. Regardless of which explanation may be true, the implications for clinical practices and recreational practices of meditation are profound as we would not want to waste resources and time on an intervention that is not going to be effective or anywhere better than the existing programs for promoting health and well-being. If we chose the first explanation, we have to rule out the possibility that mixed findings may be due to neglecting individual differences in the observed effects. Because group-averaged results are largely affected by the study sample—and it is possible that some study samples had individuals who were more responsive to the intervention than other study samples—this can lead to subtle or no effects on the outcomes of interest. Unfortunately, there has been a lack of knowledge regarding individual differences in response to meditation or on individual factors associated with intervention effectiveness, making it difficult to confirm either of the possibilities. Even when individual differences have been considered in the past, the study results were mostly preliminary and have yet to reach a wider audience for the studies to have a substantial influence on the scientific community and the public. Hence increasing awareness of these issues and considering individual differences are crucial for scientific investigation to accurately evaluate the effects of meditation and for clinical application of meditation practices in treating problematic symptoms to be more effective.

We will introduce the theoretical background of individual differences in treatment responsiveness and its relation to meditation research and application. To facilitate better understanding of the topic, we start by describing two notable conceptual models and frameworks particularly relevant for considering individual differences in terms of treatment planning and treatment effectiveness, namely (1) patient-centered care, and (2) aptitude (or attribute)×treatment interaction. We also discuss precision medicine, a national initiative proposed by the US government, which further demonstrates the growing societal awareness for individual variability in response to treatments, as well as governmental support for scientific research in this exciting area.

Patient-centered care

Within a medical setting healthcare services are typically provided at the level of individual, where physicians and other professionals closely interact with the patient to discuss a treatment plan and offer the necessary services. It is therefore not surprising that individual differences and preferences are widely respected and valued within healthcare systems. The patient-centered care approach is a prominent example advocating the importance of attending to individuals’ preferences, values, characteristics, and needs when providing treatment and care to patients (IOM, 2001; Rathert, Wyrwich, & Boren, 2013). It underscores the idea that patients should be at the center of the treatment process, not the middle, and should also be able to make decisions regarding their treatment and have their preferences respected and honored whenever possible (Steiger & Balog, 2010). Notably, patient-centered care does not limit the forms of treatment only to medical procedures, it is also intended to emphasize the value of respecting individuality and differences and being responsive to individual needs across any form of treatment and treatment context. This approach is relevant for psychological interventions such as cognitive behavioral therapy (CBT) and meditation-based programs that are often used within clinical settings for treating symptoms of psychiatric disorders. However, it is important to realize that the concept of patient-centered care has been around for more than 50 years and has been widely embraced by physicians, clinicians, healthcare organizations, and governments. Since 2001, the Institute of Medicine has included patient-centered care as one of the six critical aims for improving the health care system in the 21st century (IOM, 2001).

As one of the key objectives for improving the quality of health care, the philosophy of patient-centered care has been gradually realized in medical practices and has been quite successful in terms of patients’ satisfaction, relation to treatment providers, and treatment outcomes (Epstein & Street, 2011; Rathert et al., 2013; Rocco, Scher, Basberg, Yalamanchi, & Baker-Genaw, 2011). For instance, a systematic review of patient-centered care indicated that nearly all reviewed studies showed a positive relationship between patient-centered care and the patient’s satisfaction and well-being (Rathert et al., 2013). Although the impacts of patient-centered care on long-term clinical outcomes still require more thorough investigation, an overall positive trend in different outcome measures can be widely observed in most studies. The idea, however, was not without pushbacks. The debate between proponents and skeptics on whether focusing on individual needs and preferences may contradict the purpose of evidence-based treatment that is typically standardized for the general population eventually came to the conclusion that when it comes to treatment, one should consider “both the art of generalizations and the science of particulars” (Epstein & Street, 2011). The philosophy of patient-centered care has profound impacts on how we think about standardized treatment programs when providing them to individuals and how we should evaluate the outcomes of these treatment programs at the level of individuals. However, it is important to recognize that the concept of patient-centered care is easier to understand than to implement in practice, since providing patient-centered care often requires infrastructural changes to the existing healthcare facilities, as well as adequate personnel training in order to offer high-quality treatment and services (Epstein & Street, 2011). Otherwise the devoted efforts to pursue patient-centered care may appear superficial and merely theoretical. For the purpose of our discussion the conceptual implications of patient-centered care for psychological interventions is much more important than the implementation aspect of this framework.

Psychological interventions are also considered within the patient-centered care framework. When one thinks about psychological intervention or psychotherapy that does not involve medication, the image that often comes into mind is an individual-based interaction with the treatment provider, typically a clinical psychologist or therapist who devotes undivided attention to the patient and designs treatment plans specifically tailored to the needs of the individual. Within the field of psychotherapy there has always been an emphasis on individual needs and characteristics, which is consistent with the philosophy of patient-centered care (Epstein & Street, 2011). Although not all psychological interventions or therapies are focused on the individual level, group-based interventions such as meditation and CBT could also benefit from this concept of patient-centeredness. In particular, thinking through the perspective of individual patients, instructors can at least become more aware of, and attentive to, potential individual differences in needs and preferences within a group, rather than assuming that everyone in the group would share the same values and goals for the intervention. Conceptually, cherishing the value of patient-centeredness when providing psychological interventions is important for ensuring the effectiveness, satisfaction, and quality of the intervention—as is the case for medical settings.

Speaking of group-based interventions such as meditation, there has been a movement of integrating patient-centered care philosophy within complementary and alternative medicine to increase the quality and outcome of overall treatment (Maizes, Rakel, & Niemiec, 2009). Complementary and alternative medicine approaches such meditation-based interventions and other nonconventional medical therapies are frequently provided in conjunction with conventional medical treatments. Therefore, valuing and respecting individual differences in the application of meditation-based interventions would undoubtedly be pivotal for ensuring high-quality intervention. The evaluation of intervention effects could also be informed by the philosophy of patient-centered care. For instance, one encouraging work on meditation-based intervention chose to examine specific patient-centered outcomes such as self-efficacy, work productivity, and health services utilization after 1 year of intervention, rather than simply looking at conventional measures of psychological well-being (McCubbin et al., 2014). The study found that meditation-based intervention increased self-efficacy and decreased the use of health services, suggesting that such intervention is effective and that there are alternative possibilities for evaluating intervention outcomes, especially at the individual level. It also suggests examining individual-specific measures could be appropriate for future studies and potentially more sensitive for capturing improvement in well-being following interventions. Overall, the concept of patient-centered care is transforming our healthcare system and has far-reaching implications for informing both scientific research and clinical practices.

Aptitude (or attribute)×treatment interaction

We primarily discussed the philosophy of patient-centered care from a conceptual standpoint and described its promising potential for improving the outcomes of intervention. What is missing from this framework is how exactly it could be translated into helping scientific investigations to accurately evaluate intervention outcomes, since patient-centered care focuses more on improving the quality of clinical practices and intervention outcomes. However, if we look into the field of psychotherapy there is a notable conceptual framework geared toward studying individual differences in response to psychological intervention.

The aptitude (or attribute) x treatment interaction (ATI) was a research paradigm and conceptual framework proposed by Lee Cronbach in the early 1950s that linked individual differences to treatment outcomes. In this paradigm, aptitude (or attribute) refers to any relevant individual difference variables identified at the baseline (prior to any treatmen...