PLoS ONE
February 18, 2015
Fernanda Palhano-Fontes, Kátia C. Andrade, Luís Fernando Tófoli et al.
461 citations
Ayahuasca, a psychedelic brew used traditionally by Amazonian Amerindians, significantly reduces activity in key hubs of the Default Mode Network (DMN), specifically the Posterior Cingulate Cortex (PCC)/Precuneus and medial Prefrontal Cortex (mPFC), as measured by fMRI in ten experienced subjects. Functional connectivity within the PCC/Precuneus also decreased after intake, while the orthogonality between the DMN and task-positive network showed no significant change. These findings suggest that the altered state of consciousness induced by Ayahuasca, similar to effects from psilocybin, meditation, and sleep, involves modulation of DMN activity and connectivity.
Human Brain Mapping
September 16, 2011
Dráulio Barros de Araújo, Sidarta Ribeiro, Guillermo Cecchi et al.
241 citations
Ayahuasca, a hallucinogenic brew containing serotonergic agonists and reuptake inhibitors, triggers vivid visual imagery during ceremonies. Using functional magnetic resonance imaging while participants performed a closed-eyes imagery task, the brew produced a robust increase in activation across occipital, temporal, and frontal brain areas. In the primary visual area, activation levels matched those of natural image viewing with eyes open. This effect correlated with individual perceptual changes measured by psychiatric scales. Activity in areas BA30 and BA37, linked to episodic memory and contextual associations, was also potentiated. Modulation of BA10, involved in prospective imagination and working memory, was detected. The findings suggest Ayahuasca seeings arise from an extensive network for vision, memory, and intention, lending a sense of reality to inner experiences.
European Neuropsychopharmacology
January 16, 2015
José Carlos Bouso, Fernanda Palhano-Fontes, Antoni Rodrı́guez-fornells et al.
221 citations
Regular use of the psychedelic brew ayahuasca is associated with thinning of the posterior cingulate cortex (PCC), a key hub of the default mode network. In a comparison of 22 regular ayahuasca users and 22 matched controls, MRI scans revealed significant cortical thinning in midline brain structures among users. The degree of thinning correlated with both the intensity and duration of ayahuasca use and with scores on self-transcendence, a personality trait linked to spirituality and transpersonal feelings. While direct causation cannot be established, the findings suggest that sustained psychedelic use may induce structural brain changes underlying attentional processes, self-referential thought, and previously reported personality shifts in long-term users.
Scientific Reports
January 15, 2014
Natália Bezerra Mota, Raimundo Furtado, Pedro Maia et al.
159 citations
Analyzing speech graphs from dream reports can distinguish people with schizophrenia from those with bipolar disorder and non-psychotic controls. People with schizophrenia showed reduced speech connectivity in both waking and dream reports, which correlated with negative and cognitive symptoms. People with bipolar disorder were indistinguishable from controls in waking reports but showed significantly less connectivity in dream reports. Dream-related speech graph attributes outperformed psychometric scores and waking data for sorting groups. The findings suggest that dreaming exposes differences in memory processing across individuals while waking dampens distinctions, and point toward a fast, low-cost, language-invariant tool for psychiatric diagnosis.
Scientific reports
October 9, 2017
Vanja Dakic, Juliana Minardi Nascimento, Rafaela Costa Sartore et al.
137 citations
5-MeO-DMT, a serotonin-like molecule found in traditional Amerindian medicine, alters the protein landscape of human cerebral organoids. Out of 6,728 identified proteins, 934 were differentially expressed after treatment. Computational analysis confirmed previously reported anti-inflammatory effects and revealed modulation of proteins involved in long-term potentiation, dendritic spine formation, cellular protrusion, microtubule dynamics, and cytoskeletal reorganization. These findings provide initial molecular insights into how this compound may affect human brain metabolism.
Scientific Reports
August 2, 2013
Fábio V. Caixeta, Alianda Maira Cornélio, Robson Scheffer-Teixeira et al.
134 citations
Blocking NMDA receptors with ketamine alters how different brain rhythms interact in the hippocampus, a region critical for memory and attention. In awake rats, ketamine (25, 50, and 75 mg/kg) increased fast brain oscillations (gamma and high-frequency oscillations) across all layers of the CA1-dentate axis, while changes in slower theta waves depended on location. Ketamine also increased phase coherence of fast oscillations across hippocampal layers. The coupling between theta waves and fast oscillations changed in a dose-dependent way: theta-high-frequency coupling increased at all doses, but theta-gamma coupling increased only at the lowest dose and was disrupted at the highest dose. These findings indicate that NMDA receptor blockade disrupts neural coordination patterns linked to cognitive functions impaired in schizophrenia.
PLoS ONE
November 30, 2020
Natália Bezerra Mota, Janaína Weissheimer, Marina Ribeiro et al.
71 citations
Dreams during the 2019-20 coronavirus outbreak reveal psychological distress. Analyzing 239 dream reports from 67 individuals, dreams during the Coronavirus disease 2019 (COVID-19) Pandemic showed more anger and sadness words. These dreams also linked to "contamination" and "cleanness." Intriguingly, these dream characteristics explained 40% of the variation in psychological suffering related to social isolation, relevant for Psychiatry and Medicine. This underscores how the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) crisis impacts Sleep and Wakefulness Research, including mind wandering and attention, reflecting widespread Coronavirus Infections' effects.
Revista brasileira de psiquiatria (Sao Paulo, Brazil : 1999)
January 1, 2021
Alvaro V Jardim, Dora V Jardim, Bruno Rasmussen Chaves et al.
54 citations
In Brazil's first clinical trial of MDMA-assisted psychotherapy for post-traumatic stress disorder (PTSD), three patients with PTSD from sexual abuse completed treatment. The protocol involved 15 weekly therapy sessions, with three sessions including orally administered MDMA combined with psychotherapy and music, spaced about a month apart. Two months after the final MDMA session, all three patients showed clinically significant improvement, with CAPS-4 scores dropping by more than 30% from baseline. Final scores were 61, 27, and 8, down from 90, 78, and 72. No serious adverse events occurred; common side effects were somatic pains and anguish. Secondary outcomes also improved. MDMA-assisted psychotherapy could become a viable PTSD treatment in Brazil.
Psychological medicine
March 1, 2023
Isabel Wießner, Marcelo Falchi, Fernanda Palhano-Fontes et al.
53 citations
In a randomized, double-blind, placebo-controlled, crossover study, 24 healthy volunteers received 50 μg LSD or placebo. LSD produced psychedelic experiences, including altered consciousness, mystical experiences, ego-dissolution, and mildly challenging experiences, and increased aberrant salience and suggestibility, but not mindfulness. LSD-induced aberrant salience correlated strongly with complex imagery, mystical experiences, and ego-dissolution. Suggestibility changes from LSD did not correlate with other effects. The results suggest the LSD state resembles psychosis and may offer a therapeutic tool, with mystical experiences linking the psychosis model and therapeutic potential. Meaning attribution appears important for the LSD psychosis model, and psychedelic-assisted therapy might benefit from suggestions that foster mystical experiences.
Journal of Psychopharmacology
February 1, 2022
Isabel Wießner, Marcelo Falchi-Carvalho, Lucas Oliveira Maia et al.
43 citations
A randomized, double-blind, placebo-controlled crossover study gave 24 healthy volunteers 50 micrograms of LSD or an inactive placebo and tested creativity near the drug's peak using multiple tasks. LSD changed creativity in three ways: it increased novelty, surprise, originality, and semantic distances (pattern break); decreased utility, convergent thinking, and marginally elaboration (disorganization); and increased symbolic thinking and ambiguity (meaning). The findings suggest LSD shifts cognitive resources away from normal patterns toward new ones, and that LSD-induced symbolic thinking might aid psychedelic-assisted therapy.
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology
May 1, 2022
Isabel Wießner, Rodolfo Olivieri, Marcelo Falchi et al.
42 citations
A low dose of LSD (50 μg) produces both beneficial and detrimental cognitive effects 24 hours after administration. Compared to placebo, LSD sub-acutely improved visuospatial memory and phonological verbal fluency but impaired cognitive flexibility, as measured by fewer categories achieved and more perseveration on the Wisconsin Card Sorting Test. The findings suggest that LSD-assisted therapy might be explored for conditions involving memory and language decline, such as brain injury, stroke, or dementia, while also indicating a mixed 'afterglow and hangover' profile.
Frontiers in Human Neuroscience
January 1, 2013
Sérgio A. Mota-Rolim, Zé H. Targino, Bryan C. Souza et al.
42 citations
Dreams typically involve actions, known people, sounds, and colors, and often relate to upcoming plans or recent memories. Nightmares frequently feature anxiety, being stalked, or other unpleasant sensations. Lucid dreaming—knowing one is dreaming—was experienced at least once by 77% of a Brazilian sample of 3,427 people, but episodes were brief (under one minute for 48%) and control was rare (29%). Lucid dreaming was more common when people did not need to wake early or were under stress, conditions that increase REM sleep. These findings suggest lucid dreaming is a widespread but unstable human experience, consistent with data from other continents.
PLoS ONE
July 23, 2020
Joshua M. Martin, Danyal Wainstein Andriano, Natália Bezerra Mota et al.
41 citations
Dream reports collected after rapid eye movement (REM) sleep are typically longer, more vivid, and more story-like than those from non-REM sleep, but traditional measures may be confounded by report length. By analyzing 133 dream reports from 20 participants as non-semantic directed word graphs, researchers found that REM dream reports have greater connectedness—words recur with longer range—compared to N2 sleep reports. Graph measures predicted dream complexity, with higher connectedness and lower randomness linked to more complex reports. The largest connected component improved models using report length alone for predicting sleep stage and complexity. Graph analysis offers an automated method to complement traditional dream report analysis.
Frontiers in Psychology
March 8, 2016
Natália B. Mota, Adara Resende, Sérgio A. Mota-Rolim et al.
38 citations
People with psychosis report more control over their lucid dreams than non-psychotic individuals, contrary to the hypothesis that lucid dreaming might be therapeutically beneficial for psychotic patients. Among 45 subjects with psychotic symptoms (25 with schizophrenia, 20 with bipolar disorder) and 28 non-psychotic controls, psychotic lucid dreamers reported controlling their dreams more frequently (67% of schizophrenia and 73% of bipolar patients) than non-psychotic lucid dreamers (23% of controls). However, lucid dreamers with psychosis showed no clinical advantage, even on measures of judgment and insight. The findings suggest psychosis may enhance the ability to control internal reality, and that training lucid dreaming in psychotic populations could potentially strengthen delusions and hallucinations rather than provide therapeutic benefit.
Conscious Cogn
December 8, 2020
Camila Sanz, Carla Pallavicini, Facundo Carrillo et al.
34 citations
Language produced under the influence of LSD shows increased entropy and reduced semantic coherence, consistent with a state of heightened neural entropy. Non-semantic analysis of speech organization revealed increased verbosity and a reduced lexicon, changes more similar to manic psychoses than to schizophrenia, as confirmed by direct comparison with reference samples. Features related to language organization allowed machine learning classifiers to identify speech under LSD with accuracy comparable to that obtained by examining semantic content. These results provide a quantitative characterization of disorganized natural speech as a landmark feature of the psychedelic state.
Frontiers in psychology
January 1, 2020
Sergio A Mota-Rolim, Kelly Bulkeley, Stephany Campanelli et al.
31 citations
Religions have long recognized lucid dreaming (LD) as an important conscious state, predating modern scientific study by millennia. Hindu texts over 2,000 years old divide consciousness into waking, dreaming (including LD), and deep sleep. Tibetan Buddhists practice Dream Yoga to recognize dreams, overcome fears, and control dream content. Islam regards LD as a valuable mental state for mystical experiences. Christian theologian Augustine described LD as a preview of the afterlife. Spiritism in the nineteenth century linked LD to out-of-body experiences. Abrahamic religions view dreams as communication with God, while Indian traditions cultivate self-awareness through LD induction techniques. These historical religious insights can inform current scientific research on LD phenomenology.
Frontiers in Neuroscience
May 8, 2019
Sérgio Mota‐rolim, Achilleas Pavlou, George Nascimento et al.
25 citations
Lucid dreaming is rare but pleasurable and has potential clinical uses, such as treating nightmares in PTSD. Researchers have been developing portable devices to induce lucid dreams. These devices detect REM sleep via EEG and then deliver visual, auditory, or tactile cues to alert the dreamer without waking them, or use transcranial alternating current stimulation of the frontal cortex. This review covers 10 such devices: DreamLight, NovaDreamer, Aurora, Remee, REM-Dreamer, ZMax, Neuroon, iBand, LucidCatcher, and Aladdin.
Psychopharmacology
June 1, 2022
Isabel Wießner, Marcelo Falchi, Fernanda Palhano-Fontes et al.
22 citations
LSD alters the stream of thought in multiple ways, increasing chaos, meaning, and abstractness at different times after ingestion. In a randomized, double-blind, placebo-controlled crossover study with 24 healthy participants, 50 μg LSD compared to placebo induced facets of mind-wandering labeled 'chaos' (discontinuity of mind, decreased sleepiness and planning), 'meaning' (deep thoughts), and 'sensation' (thoughts about odors and sounds). LSD also increased free association for abstract words, reflecting an 'abstract flow.' Chaos was strongest from 2 to 6 hours after dosing, meaning from 2 to 4 hours, sensation at 2 hours, and abstract flow at 4 hours. The findings suggest a late therapeutic window around 4 hours for psycholytic therapy.
bioRxiv (Cold Spring Harbor Laboratory)
December 6, 2019
Felipe Augusto Cini da Silva, Isis M. Ornelas, Encarni Marcos et al.
9 citations
preprint
A single dose of d-LSD, a potent serotonergic agonist, increased preference for novel objects in young and adult rats several days after treatment, but did not increase preference in old animals unless followed by a 6-day exposure to enriched environment, which rescued novelty preference to young levels. Mass spectrometry-based proteomics in human brain organoids treated with d-LSD showed upregulation of proteins from the presynaptic active zone. A computational model of synaptic connectivity in the hippocampus and prefrontal cortex suggests that d-LSD enhances novelty preference by combining local synaptic changes in mnemonic and executive regions with alterations of long-range synapses, and that better pattern separation within enriched environment explains its synergy with d-LSD in rescuing novelty preference in old animals. These results advance the use of d-LSD in cognitive enhancement.
European Neuropsychopharmacology
September 1, 2009
D. Almeida Prado, Joel Porfírio Pinto, José Alexandre S. Crippa et al.
9 citations
Ayahuasca, a traditional Amazonian brew, shows promise in psychiatry, with 66% of participants reporting significant improvement in depressive symptoms after treatment. This study involved 100 individuals seeking relief from mental health issues. Participants experienced enhanced emotional well-being and altered perspectives on life, suggesting a blend of psychological and philosophical enlightenment. The findings highlight ayahuasca's potential as a medicinal tool within the broader context of psychedelics and drug studies, offering new insights into the intersection of psychology, art, and anthropology in understanding human experience.
The Journal of neuroscience : the official journal of the Society for Neuroscience
May 14, 2025
Çağatay Demirel, Jarrod Gott, Kristoffer Appel et al.
8 citations
Lucid dreaming, where a person becomes aware they are dreaming, is linked to REM sleep. To overcome previous research limitations, a new preprocessing pipeline was applied to pooled EEG data from multiple labs. Sensor-level differences between lucid and nonlucid REM sleep were minimal, but source-level analysis revealed reduced beta power (12-30 Hz) in right central and parietal areas, including the temporoparietal junction, during lucid dreaming. Alpha-band (8-12 Hz) connectivity increased compared to nonlucid REM sleep. During eye signaling of lucidity, gamma1 power (30-36 Hz) increased in right temporo-occipital regions, including the precuneus, and interhemispheric gamma1 connectivity rose. These patterns suggest shifts in network communication underlying changes in perception, self-awareness, and cognitive control.
Scientific reports
May 17, 2024
Annie C Souza, Bryan C Souza, Arthur França et al.
7 citations
The psychedelic 5-MeO-DMT alters brain activity in rats by increasing delta waves and decreasing theta waves in the hippocampus, changes that are not explained by movement. It also reduces slow and mid gamma power and disrupts theta phase modulation. The overall brain state resembles patterns seen during slow-wave sleep and REM sleep, suggesting that the drug's effects involve mixing waking behavior with sleep-like neural oscillations.
medRxiv
May 21, 2020
Natália Bezerra Mota, Janaína Weissheimer, Marina Ribeiro et al.
7 citations
preprint
Dreams during the COVID-19 pandemic contained a higher proportion of anger and sadness words and were semantically more similar to the terms contamination and cleanness compared to dreams from before the outbreak. These dream features were associated with mental suffering related to social isolation, explaining 39% of the variance in negative symptoms measured by the PANSS scale. The findings suggest that pandemic dreams reflect mental suffering, fear of contagion, and changes in daily habits.
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology
March 1, 2023
Isabel Wießner, Marcelo Falchi, Dimitri Daldegan-Bueno et al.
6 citations
Low to moderate doses of LSD alter language structure, semantics, and vocabulary over time. In a double-blind, placebo-controlled crossover study, 24 healthy volunteers (age 35±11, 33% women) received 50 μg LSD or placebo. LSD reduced verbosity, lexicon, and connectivity in speech networks from 1.5 to 4 hours, decreased semantic distances between words from 2 to 24 hours, and shifted vocabulary related to grammar, persons, time, space, and biological processes from 1.5 to 24 hours. Simpler, disconnected structure and increased semantic similarity may reflect cognitive impairments, while vocabulary changes may indicate subjective perceptual shifts. Automated language analysis could offer unconstrained insights into psychedelic cognition.
NeuroImage
October 17, 2022
Natália Bezerra Mota, Ernesto Soares, Edgar Altszyler et al.
5 citations
Visual and emotional aspects of waking memories follow different paths as people fall asleep. Healthy adults viewed an emotional image, then were awakened seconds to minutes later during wakefulness, N1, or N2 sleep stages. Semantic similarity between the image and subsequent hypnagogic imagery—the 'image residue'—persisted and even increased during N1 sleep, lasting longer with more time in that stage. In contrast, the emotional tone of the image—the 'affect residue'—gradually faded as sleep progressed, becoming neutralized and reaching its lowest point during N2. Brain theta power (4.5–6.5 Hz) during N1 was inversely related to image residue. These findings suggest that visual content and strong negative emotions may decouple at sleep onset, possibly aiding emotional processing.