Michael Lifshitz

Functional neuroanatomy of meditation: A review and meta-analysis of 78 functional neuroimaging investigations

Meditation is a family of mental practices that encompasses a wide array of techniques employing distinctive mental strategies. We systematically reviewed 78 functional neuroimaging (fMRI and PET) studies of meditation, and used activation likelihood estimation to meta-analyze 257 peak foci from 31 experiments involving 527 participants. We found reliably dissociable patterns of brain activation and deactivation for four common styles of meditation (focused attention, mantra recitation, open monitoring, and compassion/loving-kindness), and suggestive differences for three others (visualization, sense-withdrawal, and non-dual awareness practices). Overall, dissociable activation patterns are congruent with the psychological and behavioral aims of each practice. Some brain areas are recruited consistently across multiple techniques-including insula, pre/supplementary motor cortices, dorsal anterior cingulate cortex, and frontopolar cortex-but convergence is the exception rather than the rule. A preliminary effect-size meta-analysis found medium effects for both activations (d=0.59) and deactivations (d=-0.74), suggesting potential practical significance. Our meta-analysis supports the neurophysiological dissociability of meditation practices, but also raises many methodological concerns and suggests avenues for future research.

The self-regulating brain and neurofeedback: Experimental science and clinical promise

Neurofeedback, one of the primary examples of self-regulation, designates a collection of techniques that train the brain and help to improve its function. Since coming on the scene in the 1960s, electroencephalography-neurofeedback has become a treatment vehicle for a host of mental disorders; however, its clinical effectiveness remains controversial. Modern imaging technologies of the living human brain (e.g., real-time functional magnetic resonance imaging) and increasingly rigorous research protocols that utilize such methodologies begin to shed light on the underlying mechanisms that may facilitate more effective clinical applications. In this paper we focus on recent technological advances in the field of human brain imaging and discuss how these modern methods may influence the field of neurofeedback. Toward this end, we outline the state of the evidence and sketch out future directions to further explore the potential merits of this contentious therapeutic prospect.

Empirical neuroenchantment: from reading minds to thinking critically

While most experts agree on the limitations of neuroimaging, the unversed public—and indeed many a scholar—often valorizes brain imaging without heeding its shortcomings. Here we test the boundaries of this phenomenon, which we term neuroenchantment. How much are individuals ready to believe when encountering improbable information through the guise of neuroscience? We introduced participants to a crudely-built mock brain scanner, explaining that the machine would measure neural activity, analyze the data, and then infer the content of complex thoughts. Using a classic magic trick, we crafted an illusion whereby the imaging technology seemed to decipher the internal thoughts of participants. We found that most students—even undergraduates with advanced standing in neuroscience and psychology, who have been taught the shortcomings of neuroimaging—deemed such unlikely technology highly plausible. Our findings highlight the influence neuro-hype wields over critical thinking.

Neurofeedback, Self-Regulation, and Brain Imaging: Clinical Science and Fad in the Service of Mental Disorders

Neurofeedback draws on multiple techniques that propel both healthy and patient populations to self-regulate neural activity. Since the 1970s, numerous accounts have promoted electroencephalography-neurofeedback as a viable treatment for a host of mental disorders. Today, while the number of health care providers referring patients to neurofeedback practitioners increases steadily, substantial methodological and conceptual caveats continue to pervade empirical reports. And yet, nascent imaging technologies (e.g., real-time functional magnetic resonance imaging) and increasingly rigorous protocols are paving the road towards more effective applications and a better scientific understanding of the underlying mechanisms. Here, we outline common neurofeedback methods, illuminate the tenuous state of the evidence, and sketch out future directions to further unravel the potential merits of this contentious therapeutic prospect.

Posture alters human resting-state

Neuroimaging is ubiquitous; however, neuroimagers seldom investigate the putative impact of posture on brain activity. Whereas participants in most psychological experiments sit upright, many prominent neuroimaging techniques (e.g., functional magnetic resonance imaging (fMRI)) require participants to lie supine. Such postural discrepancies may hold important implications for brain function in general and for fMRI in particular. We directly investigated the effect of posture on spontaneous brain dynamics by recording scalp electrical activity in four orthostatic conditions (lying supine, inclined at 45°, sitting upright, and standing erect). Here we show that upright versus supine posture increases widespread high-frequency oscillatory activity. Our electroencephalographic findings highlight the importance of posture as a determinant in neuroimaging. When generalizing supine imaging results to ecological human cognition, therefore, cognitive neuroscientists would benefit from considering the influence of posture on brain dynamics.

Brain correlates of hypnosis: A systematic review and meta-analytic exploration

HIGHLIGHTSWe conducted a comprehensive review and meta‐analysis of brain‐imaging studies on hypnosis.Hypnotic phenomena are associated with modulations of core brain networks supporting higher‐order cognition.Our meta‐analytic results further reveal that hypnosis relates to increased activity in higher‐order visual areas.We present an overarching synthesis linking these neural patterns to top‐down models of hypnosis. ABSTRACT Imaging of the living human brain elucidates the neural dynamics of hypnosis; however, few reliable brain patterns emerge across studies. Here, we methodically assess neuroimaging assays of hypnosis to uncover common neural configurations using a twofold approach. First, we systematically review research on the neural correlates of hypnotic phenomena; then, we meta‐analyze these collective data seeking specific activation and deactivation patterns that typify hypnosis. Anchored around the role of top‐down control processes, our comprehensive examination focuses on the involvement of intrinsic brain networks known to support cognitive control and self‐referential cognition, including the executive, salience, and default networks. We discuss how these neural dynamics may relate to contemporary theories of hypnosis and show that hypnosis correlates with activation of the lingual gyrus—a brain region involved in higher‐order visual processing and mental imagery. Our findings help to better understand the neurobiological substrates comprising the appellation hypnosis.

Suggestion overrides automatic audiovisual integration

Cognitive scientists routinely distinguish between controlled and automatic mental processes. Through learning, practice, and exposure, controlled processes can become automatic; however, whether automatic processes can become deautomatized - recuperated under the purview of control - remains unclear. Here we show that a suggestion derails a deeply ingrained process involving involuntary audiovisual integration. We compared the performance of highly versus less hypnotically suggestible individuals (HSIs versus LSIs) in a classic McGurk paradigm - a perceptual illusion task demonstrating the influence of visual facial movements on auditory speech percepts. Following a posthypnotic suggestion to prioritize auditory input, HSIs but not LSIs manifested fewer illusory auditory perceptions and correctly identified more auditory percepts. Our findings demonstrate that a suggestion deautomatized a ballistic audiovisual process in HSIs. In addition to guiding our knowledge regarding theories and mechanisms of automaticity, the present findings pave the road to a more scientific understanding of top-down effects and multisensory integration.

Can expectation enhance response to suggestion? De-automatization illuminates a conundrum

Disparate theoretical viewpoints construe hypnotic suggestibility either as a stable trait, largely determined by underlying cognitive aptitude, or as a flexible skill amenable to attitudinal factors including beliefs and expectations. Circumscribed findings support both views. The present study attempted to consolidate these orthogonal perspectives through the lens of expectancy modification. We surreptitiously controlled light and sound stimuli to convince participants that they were responding strongly to hypnotic suggestions for visual and auditory hallucinations. Extending our previous findings, we indexed hypnotic suggestibility by de-automatizing an involuntary audiovisual phenomenon-the McGurk effect. Here we show that, regardless of expectancy modification, the experimental procedure led to heightened expectations concerning future hypnotic response. We found little effect of expectation, however, on actual response to suggestion. Our findings intimate that, at least in the present experimental context, expectation hardly correlates with--and is unlikely to be a primary determinant of--high hypnotic suggestibility.

Hypnosis as neurophenomenology

Hypnosis research binds phenomenology and neuroscience. Here we show how recent evidence probing the impact of hypnosis and suggestion can inform and advance a neurophenomenological approach. In contrast to meditative practices that involve lengthy and intensive training, hypnosis induces profound alterations in subjective experience following just a few words of suggestion. Individuals highly responsive to hypnosis can quickly and effortlessly manifest atypical conscious experiences as well as override deeply entrenched processes. These capacities open new avenues for suspending habitual modes of attention and achieving refined states of meta-awareness. Furthermore, hypnosis research sheds light on the effects of suggestion, expectation, and interpersonal factors beyond the narrow context of hypnotic procedures. Such knowledge may help to further foster phenomenological interviewing methods, improve experiential reports, and elucidate the mechanisms of contemplative practices. Incorporating hypnosis and suggestion into the broader landscape of neurophenomenology, therefore, would likely help bridge subjective experience and third-person approaches to the mind.

Varieties of attention in hypnosis and meditation

In their commentary, Oakley and Halligan (2011) echo their recent thoughts regarding the cognitive neuroscience of hypnosis and suggestion (Oakley & Halligan, 2009, 2010). Here we address some of the issues they raise concerning the quest for neuropsychological markers of hypnotic states, the use of hypnotic vs. posthypnotic suggestions, and the potential for other forms of atypical attention such as meditative practices to elucidate hypnosis and de-automatization. Oakley and Halligan twice allude to the paucity of data indicating a special neuropsychological ‘‘state’’ of hypnosis sometimes known as ‘‘trance’’ (2011). The authors note, however, that recent investigations show some promise of identifying a neural marker of hypnosis. Whereas some evidence, including our own research, supports the idea that hypnotic phenomena typically follow suggestions even in the absence of a formal induction procedure (Mazzoni et al., 2009; McGeown et al., 2012; Raz, Kirsch, Pollard, & Nitkin-Kaner, 2006), other research findings may serve to support a distinctive physiological marker unique to hypnosis or to hypnotic suggestions (e.g., Cojan et al., 2009; Demertzi et al., 2011; Pyka et al., 2011; Raz, Fan, & Posner, 2005; Terhune, Cardena, & Lindgren, 2010; Vanhaudenhuyse et al., 2009). Scholars, however, hardly agree even about the behavioral and phenomenological characteristics that typify ostensible hypnotic planes. For example, distinct sub-types of highly hypnotically suggestible individuals seem to diverge in their experience and behavior throughout hypnosis, challenging the view of hypnosis as a unitary concept (Terhune, Cardena, & Lindgren, 2011). In addition, the literature provides mixed accounts of how psychological factors such as context, sense of control, relaxation, and expectation relate to hypnosis (Kihlstrom, 2008). An adequate psychological model, therefore, would be instrumental to understanding hypnosis from a physiological perspective. In research settings, as in clinical practice, specific suggestions often accompany hypnosis. Few reports, however, have investigated brain and behavioral correlates of ‘‘neutral’’ hypnosis sans post-induction suggestions (Cardena, 2005; Cardena, Jonsson, Terhune, & Marcusson-Clavertz, 2012; Kihlstrom & Edmonston, 1971; McGeown, Mazzoni, Venneri, & Kirsch, 2009). These few published accounts, moreover, rarely control for the effects of implicit suggestions—for relaxation, drowsiness, and focused attention—that are ubiquitous in classic hypnotic inductions. In addition, it appears that the influence of neutral hypnosis is different from that of hypnosis with explicit suggestions. For example, in response to incongruent Stroop stimuli, highly hypnotically suggestible individuals demonstrated increased conflict-related brain activity in the anterior cingulate cortex (ACC) following neutral induction (Egner, Jamieson, & Gruzelier, 2005); conversely, when offered an explicit suggestion to perceive the stimuli as meaningless symbols, participants showed decreased fMRI signal in the ACC (Raz et al., 2005). Further research, therefore, would need to carefully tease apart such hypnotic variations. Whether or not hypnosis involves distinct neurocognitive indices, posthypnotic suggestion (PHS) provides a useful experimental alternative to hypnotic suggestion. PHS refers to a condition during common wakefulness following termination of the hypnotic experience, wherein a subject is compliant with a suggestion made during the hypnotic episode. Thus, PHS keeps cognitive performance untarnished by potential confounding factors associated with the ritual of hypnosis. Oakley