Progress in brain research
January 1, 2019
Tracy Brandmeyer, Arnaud Delorme, Helané Wahbeh
143 citations
Meditation research has grown substantially over the last 30 years, emerging from contemplative and spiritual traditions. This chapter reviews meditation classifications, which remain varied and subjective, and suggests broader multidimensional models for future improvement. Phenomenological studies, though few, are increasing and link subjective experience to neurophysiology. EEG oscillatory studies are inconclusive due to heterogeneity in meditation styles and practitioners. Neuroimaging reveals common patterns during meditation and in long-term practitioners, reflecting general similarities, but most patterns differ across traditions. Research on attention and emotion regulation mechanisms is discussed. Evidence shows positive benefits for stress reduction, anxiety, depression, and pain in some clinical populations, though methodological and conceptual issues remain.
Progress in brain research
January 1, 2005
Christopher C. French
70 citations
No Summary
Progress in brain research
January 1, 2018
John Martin Corkery
62 citations
Ibogaine, a hallucinogenic alkaloid from the Iboga shrub, has been used for centuries in West African religious ceremonies for spiritual enlightenment. Since the 1960s, it has been used in detoxification treatments to reduce cravings for substances like alcohol, cocaine, methamphetamine, opiates, and nicotine, often in non-medical settings without robust clinical trials. This chapter overviews potential benefits of such research while highlighting serious adverse effects from undiagnosed conditions or concurrent drug use. It updates the 33 known deaths globally, including 5 in the UK. A safer congener, 18-MC, is undergoing clinical trials. The chapter calls for better opiate detoxification treatments amid rising opioid fatalities and urges careful risk assessments, accurate recording of outcomes, and publication of deaths.
Progress in brain research
January 1, 2009
Neil Levy, Julian Savulescu
62 citations
Neuroimaging evidence suggests that some patients diagnosed as being in a persistent vegetative state are actually conscious. This paper critically examines that evidence, arguing that while alternative interpretations remain possible, it strongly suggests consciousness in some patients. However, the ethical significance is less than often assumed. Different kinds of consciousness have different moral weight: phenomenal consciousness (qualitative feel) makes patients moral patients whose welfare matters, but only access consciousness (global availability of information to cognitive systems) confers personhood with full moral status. Further research is needed to determine whether these patients possess the sophisticated access consciousness required for personhood.
Progress in brain research
January 1, 2023
Ruben E Laukkonen, Matthew D Sacchet, Henk Barendregt et al.
56 citations
Meditation practitioners report being able to induce a total absence of consciousness lasting up to seven days, known as cessation or nirodha samāpatti. Unlike sleep, individuals in this state cannot be woken by external stimulation, experience no sense of time or tiredness, and have a stiff rather than relaxed body. Emerging from cessation is said to produce profound effects such as sudden clarity, openness, and insights. This paper outlines the historical context, presents preliminary data from two labs, sets a research agenda, and provides an initial framework for understanding these experiences. It integrates classical Buddhist concepts of nirodha and nirodha samāpatti into current cognitive-neurocomputational and active inference frameworks of meditation.
Progress in brain research
January 1, 2009
50 citations
No Summary
Progress in brain research
January 1, 2018
Joseph P Barsuglia, Martin Polanco, Robert Palmer et al.
37 citations
A 31-year-old male military veteran with moderate alcohol use disorder received sequential treatment with ibogaine hydrochloride (1550mg, 17.9mg/kg) on day 1 and vaporized 5-MeO-DMT (bufotoxin source 50mg, estimated 5-7mg) on day 3 at an inpatient clinic in Mexico. SPECT neuroimaging before and 3 days after treatment showed increased brain perfusion in bilateral caudate nuclei, left putamen, right insula, and temporal, occipital, and cerebellar regions. The patient reported improved mood, cessation of alcohol use, and reduced cravings at 5 days, sustained at 1 month, with partial return to mild alcohol use at 2 months. The findings suggest short-term therapeutic outcomes and warrant further investigation.
Progress in brain research
January 1, 2018
Felix Müller, Matthias E Liechti, Undine E Lang et al.
32 citations
Studies of hallucinogenic drugs on the resting brain show some consistent findings: psilocybin, LSD, and ayahuasca all decrease cerebral blood flow and increase global functional connectivity in the precuneus and thalamus. LSD also consistently reduces functional connectivity within distinct resting state networks. However, results for connectivity between networks and blood flow in other brain regions show little convergence. These studies are limited by small sample sizes and potential bias from unspecific drug effects on physiology and the vascular system. Current evidence suggests neuroimaging may help reveal the neural correlates of hallucinogenic effects.
Progress in brain research
January 1, 2023
Cheng-Ta Li
25 citations
Treatment-resistant depression (TRD) describes patients with major depressive disorder who do not respond adequately to antidepressant drugs. Compared to those without TRD, affected individuals have lower health-related quality of life, more functional impairment and productivity loss, and higher healthcare costs, imposing a massive burden on individuals, families, and society. A lack of consensus on the definition of TRD limits comparison of treatment efficacy across trials and results in scarce treatment guidelines specifically for TRD. This chapter reviews common issues including definitions of an adequate antidepressant trial and TRD, prevalence and clinical outcomes, staging models, variations in definitions, and up-to-date treatment options such as pharmacological strategies, psychotherapeutic interventions, neurostimulation, glutamatergic compounds, and experimental agents.
Progress in brain research
January 1, 2023
Vasileia Kotoula, Jennifer W Evans, Claire Punturieri et al.
17 citations
Imaging studies of treatment-resistant depression (TRD) have examined brain activity, structure, and metabolite concentrations to identify critical areas of investigation and potential treatment targets. This chapter reviews findings from structural MRI, functional MRI, and magnetic resonance spectroscopy. Decreased connectivity and metabolite concentrations in frontal brain areas appear to characterize TRD, though results are not consistent across studies. Treatments including rapid-acting antidepressants and transcranial magnetic stimulation have shown some efficacy in reversing these changes while alleviating depressive symptoms. However, few TRD imaging studies exist, often with small sample sizes or varied methods, making firm conclusions difficult. Larger studies with unified hypotheses and data sharing could improve characterization of the illness and identify new treatment targets.
Progress in brain research
January 1, 2019
Stephen Parker
15 citations
Consciousness research in cognitive neuroscience has largely focused on collaborations with Buddhist meditators, but an earlier thread from the 1960s Menninger Foundation studies with Swāmī Rāma remains underexplored. Those studies demonstrated the ability to enter deep, non-REM delta wave sleep while maintaining awareness (yoga-nidrā), offering potential benefits for relaxation and mindful awareness, and a path to deeper meditative states (samādhi) and turīya. This chapter aims to elucidate yoga-nidrā using traditional and contemporary descriptions, generate testable hypotheses, and address methodological challenges in training subjects capable of this state.
Progress in brain research
January 1, 2005
Lionel Naccache
13 citations
Recent advances in understanding the brain's role in consciousness come from studying both brain-damaged patients and healthy people. Certain neuropsychological syndromes, like blindsight, visual form agnosia, and neglect, reveal dissociations that point to principles of how consciousness works in the brain. These principles are tested in healthy subjects using experimental psychology and brain imaging. This chapter reviews findings on visual phenomenal consciousness, highlighting four general principles demonstrated through conditions like visual illusions and subliminal perception. It also outlines a scientific model of consciousness based on a 'global workspace' that integrates the reviewed data.
Progress in brain research
January 1, 2021
Guy A Higgins, Edward M Sellers
10 citations
Nicotine dependence, primarily from smoking and vaping, is a leading cause of preventable death, and current pharmacotherapies—nicotine replacement, bupropion, and varenicline—have limited efficacy. This chapter reviews serotonin-targeted approaches, including selective serotonin reuptake inhibitors (SSRIs), 5-HT2A receptor agonists like psilocybin, 5-HT2C receptor agonists such as lorcaserin, and 5-HT2A receptor antagonists like pimavanserin. Psilocybin shows the most promise for smoking abstinence, but findings are preliminary and face approval challenges. Preclinical tests indicate distinct profiles for these drugs, and emerging biomarkers may enable personalized smoking cessation treatment.
Progress in brain research
January 1, 2023
Prakash Chandra Kavi
7 citations
Conscious awareness can persist during dreamless sleep, a phenomenon documented in Indo-Tibetan meditation traditions and termed lucid dreamless sleep or Yoga Nidra. This state involves maintaining tonic alertness after sleep onset through sleep stages, including slow-wave activity, until awareness eventually fades. It is distinct from hypnagogic hallucinations and lucid dreaming, offering access to subtler states of consciousness and deeper silence. However, no sleep studies have yet validated this phenomenology, so the authors propose an experimental methodology similar to lucid dreaming experiments to test it.
Progress in brain research
January 1, 2023
Mu-Hong Chen, Pei-Chi Tu, Tung-Ping Su
3 citations
Psychedelic drugs such as ketamine and psilocybin rapidly alter consciousness and neuroplasticity by modulating N-methyl-d-aspartate receptors and 5-hydroxytryptamine receptors. The US Food and Drug Administration approved esketamine for treatment-resistant depression in 2019 and for major depressive disorder with suicidal ideation in 2020. Phase 2 clinical trials have also found rapid and sustained antidepressant effects of psilocybin in patients with treatment-resistant depression. This chapter discusses the complex relationships among consciousness, neuroplasticity, and novel rapid-acting antidepressants, along with their possible neurological mechanisms.
Progress in brain research
January 1, 2023
Michele Pellegrino, Joseph Glicksohn, Fabio Marson et al.
3 citations
Immersion in the OVO Whole-Body Perceptual Deprivation chamber, a homogeneous sensory environment, consistently produces positively connotated, bodily-oriented, and cognitively dedifferentiated subjective states in most people. Semi-structured interviews with 32 participants, analyzed by three independent evaluators, showed significant consensus on experiences such as softened boundaries across time and sensory modalities. These subjective findings align with prior electrophysiological results that reported increased delta and beta activity in the left inferior frontal cortex and left insula during immersion.
Progress in brain research
January 1, 2025
Handersson Barros, Marcelo Falchi-Carvalho, Lucas O Maia et al.
2 citations
Psychedelic experiences, particularly those from DMT, are often intense and hard to put into words, which complicates therapeutic integration. In a Phase I clinical trial, participants created mandalas as a nonverbal expressive tool. The mandalas helped them symbolically express subjective content that was difficult to verbalize, thereby supporting integration. Despite this promise, expressive tools remain underused in psychedelic clinical protocols. Including art may enhance therapeutic benefits by deepening understanding and meaning of the experience.
Progress in brain research
January 1, 2025
Nethmini Navoda Sirimanne, Nupur Dahiya, Garbis Papazian et al.
1 citation
A review of clinical trials, systematic reviews, meta-analyses, and neuroscientific studies indicates that mindfulness and meditation practices can enhance cognitive function, emotional resilience, and overall mental health in older adults. These benefits appear to arise through mechanisms such as neuroplasticity, increased gray matter density, improved autonomic balance, and reduced cortisol secretion. However, the evidence is limited by methodological variability across studies, and there are potential psychological risks such as anxiety or dissociative symptoms, as well as cultural sensitivity concerns. The authors conclude that mindfulness and meditation are effective therapeutic approaches for age-related emotional and cognitive impairments, but call for greater methodological standardization, cultural adaptation, and the use of digital platforms and virtual reality to improve accessibility and effectiveness.
Progress in brain research
January 1, 2024
Christine Flatten, Damisela Linares Gutiérrez, Sebastian L Kübel et al.
1 citation
A newly developed German questionnaire called the Inventory of Secular/Spiritual Wakefulness (WAKE-16) was tested in 36 expert meditators who primarily meditate in silence and 36 demographically matched non-meditators. Meditators scored significantly higher on the WAKE-16, indicating the instrument can distinguish between groups and thus has construct validity. Meditators also scored higher on mindfulness subscales of presence and acceptance, as well as on emotion regulation and body-related symbolization of emotions. Among meditators, wakefulness correlated with mindfulness, accepting one's own emotions, and experiencing overwhelming emotions; among non-meditators, only the correlation with accepting one's own emotions was significant. The findings support the WAKE-16 as a valid measure of wakefulness, defined as an expansive, stable state involving transformed vision, identity, and relationship to the world.
Progress in brain research
January 1, 2025
Jan Clefferson Costa de Freitas, Nathalia Cristina Medeiros Maia, Markone Brandão Da Silva Shanenawa et al.
This work identifies intersections between decolonial thought and psychedelic philosophy, arguing that visionary aesthetics, liminal phenomenologies, ancestral epistemologies, ethics of resistance, politics of freedom, and kaleidoscopic metaphysics offer conceptual horizons for decolonizing manifestations of the mind. Using an analytical-descriptive methodology, it aims to philosophically justify integrating decoloniality into the reflorescence of psychedelia. The authors propose that psychedelic experiences can be ways of understanding insurgent knowledges, while decolonial conceptions can serve as keys for interpreting psychedelic experiences.
Progress in brain research
January 1, 2025
Ana Cláudia Mesquita Garcia, Lucas Oliveira Maia
Individuals facing serious illnesses, especially at the end of life, often report existential and spiritual suffering, which is linked to lower quality of life, greater psychological distress, and requests for hastened death. Palliative care aims to provide holistic support, but existing options frequently fail to address profound disruptions in meaning, connection, and dignity. Psychedelic-assisted therapies, particularly those using psilocybin, have re-emerged as promising interventions that may alleviate such distress. This chapter reviews the historical and conceptual background of palliative care, analyzes existential and spiritual suffering, and examines scientific evidence on psychedelic therapies. It discusses practical, clinical, ethical, and legal considerations for integrating these therapies into palliative care, highlighting the need for spiritually informed treatment models and the urgency of innovative responses to improve quality of life and death.
Progress in brain research
January 1, 2025
Mohamad Alfateh Abou Haykal
Love and joyful memories profoundly affect the brainstem, which governs basic life functions and connects to higher emotions. Chemicals such as oxytocin, dopamine, and serotonin interact with brainstem activity, bolstering physical health and emotional resilience. Recalling positive memories activates relaxation responses, reduces stress, and enhances well-being. Practical strategies like mindfulness and intentional relationship-building help cultivate love and create positive memories. Emerging research suggests love and memory may serve as therapeutic tools for conditions like PTSD and anxiety. Nurturing these connections can increase joy and emotional fulfillment, linking neuroscience with personal development.
Progress in brain research
January 1, 2019
Zoran Josipovic
A non-representational reflexivity theory is proposed to explain the nature of consciousness-as-such, which is distinct from the contents of awareness and levels of arousal. The theory posits that consciousness-as-such is a non-conceptual, nondual awareness whose essential property is non-representational reflexivity, making it phenomenologically, cognitively, and neurobiologically unique and irreducible to any contents, functions, or states, including an indeterminate substrate. The precuneus network hypothesis for nondual awareness is discussed in relation to this reflexivity and other neural correlate hypotheses.