Neuroscience and biobehavioral reviews
October 1, 2023
Omer A Syed, Benjamin Tsang, Robert Gerlai
7 citations
Psilocybin, a psychedelic drug, is gaining interest for both recreational and clinical use. This review examines the potential of using zebrafish as a model organism in psilocybin research. It covers behavioral tests in zebrafish relevant to anxiety and social behavior, genetic manipulation methods for studying psilocybin's effects, known mechanisms of the drug, and its safety and toxicity profile. The review also discusses how psilocybin could be used in preclinical research for affective disorders. The authors conclude that zebrafish hold promise for future preclinical studies of psychedelic drugs.
Neuroscience and biobehavioral reviews
October 1, 2024
Sergey B Yurchenko
5 citations
Panpsychism and dualism are resurgent in neuroscience, posing metaphysical challenges for theories of consciousness. Integrated Information Theory (IIT) exemplifies a framework that combines elements of both, but many theories of consciousness implicitly lean toward panpsychism when they define consciousness universally, while those invoking strong emergence risk dualism. A remedy is proposed in the form of "bioprotopsychism," grounded in evolutionary biology, autopoiesis, and the free energy principle. This approach offers a minimalist account of consciousness through a triad of chemotaxis, efference copy mechanisms, and counterfactual active inference, linking weakly emergent conscious states to the brain's unconscious predictive processing and information content.
Neuroscience and biobehavioral reviews
January 1, 1982
A E Halaris
4 citations
Indoleamine psychotomimetics like LSD increase serotonin (5-HT) levels in rat brain nerve endings, particularly in synaptic vesicles, an effect not seen with mescaline. Pretreatment with reserpine shifts the serotonin increase to a juxtavesicular compartment. The serotonin increment originates from newly synthesized amine, as shown by experiments with synthesis blockers. Destruction of raphé cell bodies does not abolish LSD's effect early after lesioning, but destruction of cortical serotonin neurons with 5,7-dihydroxytryptamine does, indicating an intact nerve terminal is required. An LSD 'autoreceptor,' possibly a presynaptic serotonin receptor that inhibits release, is postulated.
Neuroscience and biobehavioral reviews
October 1, 2025
Peter Jedlicka, Martha Nari Havenith
3 citations
Spiritual and religious practices represent a major cognitive transition in evolution, rooted in complex brain structures, dynamics, and plasticity. This review examines neural mechanisms underlying such experiences, including meditation, prayer, near-death experiences, ecstatic epilepsy, psychedelic states, and spirituality changes after brain lesions. It addresses whether these experiences can be neurobiologically explained, discussing predictive processing theory's suggestion that ecstatic states may involve impaired prediction. The beneficial and therapeutic effects of spiritual routines are placed in evolutionary medicine context. The authors argue that fruitful neurospirituality research avoids both excessive reductionism and dualism, favoring limited reductionism balanced by integrative approaches from dynamical systems, complex systems, and network theory.
Neuroscience and biobehavioral reviews
June 1, 2025
Resh S Gupta, Wendy Heller, Todd S Braver
3 citations
Inconsistent findings linking anxiety, cognitive control, and mindfulness may stem from imprecise definitions and measurements of these concepts. This review argues that anxiety, cognitive control, and mindfulness are each multidimensional, and studies often examine different dimensions using varied behavioral or neural measures, leading to mixed results. The authors propose a framework that aligns specific anxiety dimensions with particular mindfulness states and interventions, predicting distinct effects on proactive versus reactive cognitive control. They suggest using precisely targeted experimental paradigms and metrics to test these relationships, and outline novel studies to rigorously evaluate the framework.
Neuroscience and biobehavioral reviews
July 1, 2026
Marcus J Glennon, Catherine I V Bird, Prateek Yadav et al.
2 citations
Setting up a psychedelic research study involves a long, arduous, and Kafkaesque process with many unstandardised challenges. These complexities challenge existing assumptions about psychiatric prescribing, the placebo effect, and definitions of selfhood. This review brings together major UK psychedelic research teams to formalise these unique considerations, addressing sociocultural, political, legal, pharmacological, safety, study design, and experiential facets. It identifies continuing areas of debate and provides a practical, experience-based guide with recommendations for policymakers and future researchers intending to set up a psychedelic study or clinical trial.
Neuroscience and biobehavioral reviews
March 1, 2026
Andrew Laurin, Hugo Bottemanne, Samuel Bulteau et al.
2 citations
A review proposes that post-traumatic stress disorder (PTSD) involves disrupted body awareness, specifically the sense of body ownership and sense of agency, which current models overlook. Using predictive processing theory, it distinguishes two PTSD subtypes. In non-dissociative PTSD, hyperprecise trauma-related prior beliefs and heightened interoceptive signals (due to amygdala and anterior insula hyperactivity) produce rigid self-representations, with cognitive processing ranked as prior, interoception, then exteroception. In the dissociative subtype, emotional over-inhibition and anterior insula hypoactivity weaken priors and interoception, while exteroception dominates (exteroception, interoception, prior). Sense of agency impairments are specific to the dissociative subtype, linked to angular gyrus hyperactivity and glutamate hypofunction. The framework suggests a dimensional model of body consciousness disruption across the PTSD spectrum and discusses therapeutic implications for top-down and bottom-up interventions.
Neuroscience and biobehavioral reviews
March 1, 2026
Hagar Tal, Malcolm Wright, Shawn Prest et al.
2 citations
Computational models of advanced meditation, particularly those using Active Inference, increasingly point to precision weighting—the confidence assigned to different model parameters—as a shared mechanism that shapes shifts in experience. Early models emphasize top-down attentional modulation toward interoception or specific objects, while later models focus on layer-specific precision re-weighting within the meditator's hierarchical generative model to target more specific phenomenology. Despite progress, minimal phenomenal experiences such as nonduality and cessations remain largely unaddressed. Few models account for increased cognitive flexibility or learning from meditation, and mechanisms behind informal practice, affective processes, and compassion traditions are underexplored.
Neuroscience and biobehavioral reviews
February 1, 2026
Jonathan M. Lieberman, Matthew D. Sacchet
2 citations
Advanced meditation, cultivated through long-term expertise, provides a unique experimental window into the core mechanisms of consciousness. Two classes of meditative phenomena are highlighted: advanced concentrative absorption (related to jhāna), where highly abstract awareness persists while typical features of consciousness fade, and meditative endpoints (related to nirodha), involving a temporary suspension of consciousness. These states serve as precise, replicable anchors for a minimal model framework that aims to identify the simplest possible form of conscious experience. Integrating advanced meditation into neuroscience offers a promising path toward isolating the neural mechanisms supporting consciousness in its most reduced and fundamental forms.
Neuroscience and biobehavioral reviews
January 1, 2026
Netta Pinhas, Nofar Eidlman, Avigail Barnea et al.
2 citations
Microdosing—taking very low doses of psychedelics like psilocybin or LSD without full-blown effects—has been promoted as a way to boost thinking skills. A meta-analysis of 14 studies with 1,614 participants found that microdosing actually reduced cognitive control, with no improvement in other cognitive domains. The type of substance, dose, or duration of microdosing did not change this result, and effects were similar whether measured while on the drug or after. This suggests microdosing may disrupt top-down cognitive control, consistent with models of how psychedelics reduce mental rigidity. More research is needed to separate temporary drug effects from lasting changes.
Neuroscience and biobehavioral reviews
May 1, 2025
C Schiemer, M J Summers, K B Stefanidis
2 citations
Acute cannabis administration alters brain electrical activity measured by EEG, particularly reducing the amplitude of the P3 event-related potential and affecting theta frequency band power (4-7 Hz) in a dose-dependent manner. A systematic review of 16 studies found that P3 amplitude decreases consistently across various THC doses, with small-to-moderate effect sizes, suggesting it may serve as a marker of recent cannabis consumption. Oscillatory theta power also changes after cannabis use, with some evidence of dose-dependent effects. However, great heterogeneity in participant characteristics and reported data limits firm conclusions, and effects in highly tolerant users, such as medicinal cannabis patients, require further study.
Neuroscience and biobehavioral reviews
July 1, 2026
Bruno Moses, Manoj K. Doss, Enzo Tagliazucchi
1 citation
The entropic brain hypothesis suggests that brain entropy—the uncertainty in brain state distributions—increases during psychedelic states and other states of expanded consciousness, while decreasing in states of diminished consciousness. Many neuroimaging studies have reported heightened entropy under psychedelics, leading some to consider entropy a reliable biomarker of the psychedelic state. This paper argues that view is oversimplified. It reviews evidence for entropy metrics, then identifies four challenges: entropy changes are not specific to psychedelics; current methods do not capture multidimensional conscious states; multiple entropy metrics exist with different interpretations and limited consistency; and there is little evidence linking brain entropy directly to phenomenal richness. The authors conclude the concept warrants further investigation and offer suggestions for future research.
Neuroscience and biobehavioral reviews
June 1, 2026
Javier Hidalgo Jiménez, Karl Kristjan Kaup, Jaan Aru
1 citation
Psychedelics such as LSD and NBOH produce complex, heterogeneous effects on brain cells, challenging the idea that they simply increase cortical excitability. A systematic review of 23 in vitro and 26 in vivo electrophysiological studies found that these compounds modulate both excitatory and inhibitory processes in a cell-type- and compartment-specific manner, with biphasic, dose-dependent, and context-sensitive responses. Activation of 5-HT2A receptors triggers intricate calcium signaling, downregulating excitatory currents and firing rates in many neurons while enhancing glutamate release and activating a subset of projection fibers. Modulation of presynaptic and extrasynaptic GluN2B-containing NMDA receptors appears central to these effects.
Neuroscience and biobehavioral reviews
October 1, 2025
Anna Vaslavski, Anna Harwood Gross, Salomon Israel et al.
1 citation
MDMA temporarily raises oxytocin levels in a time-dependent way, with the peak occurring between 150 and 200 minutes after administration, then declining. A systematic review and meta-analysis of ten studies (39 effect size estimates) found that the dose of MDMA did not significantly predict changes in oxytocin. A trend suggested that samples with more female participants showed smaller increases in oxytocin. These findings indicate that MDMA's prosocial effects may be linked to this transient oxytocin elevation, which could inform the timing of MDMA-assisted psychotherapy sessions. Standardized methods and larger studies are needed to clarify these effects.
Neuroscience and biobehavioral reviews
October 1, 2025
Brian Key, Deborah J. Brown
1 citation
The commonsense idea that feelings such as pain cause behavior is challenged. No known mechanism explains how subjectively experienced pain could directly modulate neural activity or gate ion channels. The real cause of behavior is neural activity, not the feeling of pain itself. This raises whether pain has any causal function or is merely epiphenomenal. Epiphenomenalism struggles to explain why such an attention-consuming feeling would survive evolution. The authors infer from neuroscientific evidence that pain has a novel, non-causal function: it marks neural pathways that cause behavior as salient, serving as a ground but not a cause of decision-making and action. Decisions are caused by threshold detection of accumulated evidence of pain, not by pain per se.
Neuroscience and biobehavioral reviews
August 1, 2026
Clarita Bonamino, Clara Hausen, Matthew D Sacchet
Consciousness can persist, transform, and dissolve across wakefulness, sleep, and advanced meditation. An interdisciplinary perspective reveals converging phenomena that challenge binary accounts of consciousness and highlight its graded, dynamic, and trainable nature. The interface of advanced meditation, sleep, and consciousness science constitutes a promising frontier for understanding the structure, dynamics, and limits of conscious experience. Advanced meditation offers cultivable means for modulating these dimensions, while sleep provides recurring biological states in which awareness, experiential content, embodiment, and sensory input coupling systematically dissociate. Evidence from these domains highlights states such as deep absorption meditation, cessations, lucid dreaming, sleep-wake transitions, and clear light sleep that challenge binary distinctions between consciousness and unconsciousness. An integrated, mixed-methods perspective enables a more nuanced examination of graded and minimal forms of conscious experience.
Neuroscience and biobehavioral reviews
August 1, 2026
Andrew W Corcoran, Andrew M Haun, Reinder Dorman et al.
Three theories of consciousness—Integrated Information Theory, Neurorepresentationalism, and Active Inference—are compared and contrasted in a structured adversarial collaboration. The review presents each theory's core claims, the phenomena they explain, their explanatory approaches, and methodological strategies. It outlines key hypotheses to be tested across multi-site experiments, discusses observations that would support or challenge each theory, and describes how data from disparate experiments can be formally integrated to quantify evidential support. The work also provides meta-scientific insights into the mechanics of adversarial collaboration and theory-testing, including how theories may be evaluated by the scientific progress they deliver.
Neuroscience and biobehavioral reviews
August 1, 2026
Madhur Mangalam
David Marr's influential tri-level framework for cognitive neuroscience, which separates computational goals, algorithmic implementation, and physical realization, is no longer tenable. The framework assumes cognitive goals can be specified in advance, neural processes implement algorithms, and physical substrates are interchangeable. Evidence from slime molds, planarian flatworms, bioelectric networks, and degenerate neural circuits shows these assumptions are false. The framework has survived by expanding its terminology rather than revising its theory, a pattern resembling unfalsifiability. Tinbergen's four questions reveal that developmental and evolutionary explanations were excluded. The authors argue for treating physical dynamics, morphology, and information as co-constitutive of adaptive behavior, questioning whether such behavior should be called computation.
Neuroscience and biobehavioral reviews
July 1, 2026
Athanasia Kontouli, Michael J Hove, Alexandre Lehmann et al.
Trance states induced by music, from shamanic rituals to electronic dance music raves, share common musical features and cultural narratives. Anthropological and neuroscientific evidence suggests that different forms of trance engage partially overlapping neural dynamics, including increased low-frequency brain wave synchronization and a shift from executive control networks to limbic and default mode networks. These patterns reflect the interplay of cognitive, emotional, and sensory systems, though current empirical evidence remains fragmented and methodologically heterogeneous. The review emphasizes trance as both a cultural and biological phenomenon and calls for integrating phenomenological and neurophysiological data to build comprehensive models of music-induced non-ordinary states of consciousness.
Neuroscience and biobehavioral reviews
April 1, 2026
Yanfang Xia, Boris B Quednow, Dominik R Bach
A systematic review of 100 publications found that 36 pharmacological compounds have been tested for their effects on aversive memory in healthy humans. The most studied drugs were hydrocortisone, propranolol, and D-cycloserine. Solid evidence supports propranolol's impact on memory reconsolidation, while weak evidence suggests effects of several compounds on memory encoding, consolidation, or extinction. Fifteen compounds showed significant effects in single studies without replication. The review highlights the need for greater comparability across studies.
Neuroscience and biobehavioral reviews
February 1, 2026
Mallet R Reid, Jonathan Song, Kevin F Boehnke et al.
People of color have been significantly underincluded in psychedelic-assisted therapy (PAT) research, despite facing challenges commonly addressed in PAT and often more severe symptoms. A systematic review of the past 10 years of psilocybin, MDMA, and LSD clinical trials in the United States (N = 27) found that only 3 out of 27 studies (11.11%) incorporated community-engaged research (CEnR) practices. In the rare instances CEnR was integrated, researchers used community consultation, which involves relatively little engagement with community members. The authors recommend incorporating five CEnR principles to improve representation in PAT trials: mapping and engaging local stakeholders, leveraging existing university-hospital infrastructures, co-designing research and outreach initiatives, securing dedicated CEnR resources, and establishing mechanisms for ongoing evaluation.
Neuroscience and biobehavioral reviews
November 19, 2025
Inbal Algom, Oren Shriki
Theories of consciousness offer valuable insights but lack a unifying mechanistic framework. The ConCrit hypothesis proposes that consciousness arises when neural networks operate near a critical transition point—a state of heightened sensitivity and complexity. Near-critical systems enhance the richness of internal representations and sensitivity to the system's own state, making conscious experience more likely. As the brain deviates from this critical regime, consciousness may diminish. This review examines critical brain dynamics, their theoretical and empirical links to consciousness, and outlines predictions for testing the framework.
Neuroscience and biobehavioral reviews
November 19, 2025
Daniel K Freeman, Brian Odegaard, Seung-Schik Yoo et al.
Transcranial focused ultrasound (tFUS) can stimulate the human brain non-invasively with millimeter-scale precision, targeting both cortical and deep structures. This new tool offers a potential breakthrough for studying the neural correlates of conscious perception, overcoming the coarse spatial resolution and limited depth of traditional electrical or magnetic stimulation. Because tFUS requires extensive preparation and regulatory approvals, careful experimental planning is essential. The authors provide a roadmap for using tFUS in humans to explore the neural substrate of conscious perception.
Neuroscience and biobehavioral reviews
July 1, 2022
Drummond E-Wen Mcculloch, Gitte Moos Knudsen, Frederick Streeter Barrett et al.
A large group of psychedelic imaging researchers reviewed 42 articles from 17 unique studies that used resting-state functional magnetic resonance imaging (rs-fMRI) to examine psychedelic effects. They found that nearly all studies varied in data processing and analysis methods, two datasets underpin over half of the published literature, and key outcome terms are used ambiguously. The authors recommend guidelines to improve consistency and replicability in future research, arguing that the field must balance novel methods with standardized approaches to reliably understand the neural mechanisms of psychedelics.