Scientific reports
November 12, 2024
András Sárközy, Jonathan E Robinson, Gyula Kovács
Motion-induced blindness (MIB) is an illusion where a peripheral target disappears from awareness when viewed against a moving background. This study measured how long a target remained visible at eight positions around the visual field. Disappearance times and frequencies varied significantly with target location: targets on the cardinal axes (horizontal and vertical) vanished less often and for shorter periods than those on oblique axes, and targets on the horizontal meridian vanished less than those on the vertical. These polar angle asymmetries in MIB suggest that conscious visual perception is not uniform across the visual field, with specific consistencies between visual field location and the timing of perceptual disappearances.
Scientific reports
October 23, 2024
Natali D Kisaki, Yasmim A Serra, Isa R S Rodrigues et al.
Male mice voluntarily drank ayahuasca over water when offered every other day, regardless of concentration. Extending the interval between exposures to every five days reversed this preference, producing aversion to ayahuasca, especially at higher concentrations. Frequency of exposure and concentration together influenced total ayahuasca intake during later re-exposure. These results indicate that both how often and how much ayahuasca is available determine preference in mice, which may inform therapeutic or ritualistic use.
Scientific reports
June 12, 2026
Derek H Arnold, Loren N Bouyer, Merlin Monzel
People with Aphantasia, initially characterized as having a deficit in visual imagination, often also report lacking imagined sensations in other modalities such as sound, taste, smell, touch, and body movement. These patterns of imaginative inability vary individually. Many Aphantasics report visual dreams, suggesting the deficit might be specific to volitional waking imagined sensations. This study assessed the multisensory profiles of Aphantasics' dreams and found a typical correspondence between reported multisensory dream contents and volitional waking imagined experiences, though with considerable heterogeneity. Some Aphantasics show tight associations between dream and waking imagined sensations, while others show little or no correspondence, challenging researchers to explain these diverse outcomes.
Scientific reports
June 5, 2026
Amaury C Mengin, Julie Rolling, Walid Oulehri et al.
Among 59 patients discharged from intensive care after severe COVID-19, levels of post-traumatic growth were relatively high three months later, while only 3.4% met criteria for post-traumatic stress disorder. A near-death experience occurred in 20.3% of participants. Post-traumatic growth was associated with the presence of a near-death experience, intense and intrusive memories, and higher PTSD symptom levels. The findings suggest that near-death experiences and higher distress may contribute to post-traumatic growth after ICU hospitalization.
Scientific reports
November 28, 2025
Theresa Rieger, Josefine Feuerstein, Niko A Busch et al.
The visual awareness negativity (VAN) is a brain response linked to conscious perception, typically seen when comparing perceived versus unseen visual stimuli. This study tested whether the VAN also appears during visual illusions—when people report seeing something that is not physically present. Using the sound-induced flash illusion, where a single flash accompanied by two beeps often creates the illusion of a second flash, electroencephalography (EEG) was recorded from 47 participants. Comparing illusion trials (where participants reported seeing two flashes) with non-illusion trials (where they saw only one), an enhanced negativity over posterior electrodes was observed between 250 and 300 milliseconds.
Scientific reports
November 3, 2025
Ryoichi Watanabe, Yusuke Moriguchi
Visual consciousness—the transition from unconscious to conscious perception—emerges more slowly and gradually in 5–6-year-old preschoolers than in adults. Seventeen preschoolers and 16 adults completed color and category discrimination tasks at varying stimulus onset asynchronies. Objective accuracy and subjective awareness ratings were measured. Preschoolers showed significantly larger thresholds for both objective discrimination and subjective awareness, and their emergent processes were significantly more gradual, regardless of task type. Thus, young children require longer stimulus exposure to become consciously aware of colors and objects, and their transition to consciousness is less abrupt than in adults.
Scientific reports
September 29, 2025
Nerea L Herrero, Yohann Corfdir, Aylin A Vázquez-Chenlo et al.
During sleep, consciousness can re-emerge as non-ordinary states such as lucid dreams, sleep paralysis, out-of-body experiences, and false awakenings. In an exploratory study, overnight brainwave recordings were taken from people who frequently experience these states, capturing ten episodes. Eye movement markers identified periods of lucidity. Analysis of brainwave power showed that these states are distinct from wakefulness but share features with both stage 1 and REM sleep. The findings suggest that these non-ordinary states have unique neurophysiological signatures that blend characteristics of different sleep stages.
Scientific reports
March 6, 2025
Pablo Rodríguez-San Esteban, Jose A Gonzalez-Lopez, Ana B Chica
Machine learning can decode whether someone consciously perceives a near-threshold visual stimulus from their EEG brain signals, and using time-frequency representations of the signal improves decoding accuracy over raw voltage, especially in theta and alpha frequency bands. In a task where participants viewed faint Gabor gratings and reported whether they saw them, the model successfully detected the presence or absence of a stimulus and the participant's subjective perception, but could not decode the grating's orientation. Unconscious processing of unseen stimuli was evident both behaviorally and neurally, but these unconscious representations were less stable over time and appeared only at early perceptual stages around 100 milliseconds and during response preparation.
Scientific reports
May 8, 2024
Annika Hense, Antje Peters, Maximilian Bruchmann et al.
Sustained visual awareness is associated with a negative event-related potential (ERP) that persists for the entire duration a stimulus is consciously perceived. In a visual task, participants viewed line stimuli presented for 500 or 1000 milliseconds. Some participants were informed that the lines sometimes contained a face, enabling them to see the face through visual one-shot learning, while uninformed participants did not perceive the face. Comparing brain activity between groups showed an enhanced negativity over occipitotemporal electrodes that lasted as long as the stimulus was presented. This sustained visual awareness negativity (SVAN) indicates that awareness-related brain signals correspond to the duration of a conscious percept, not just a transient onset response.
Scientific reports
April 23, 2024
Helena Hruby, Stefan Schmidt, Justin S Feinstein et al.
Floatation-REST, which minimizes sensory input by having people float in warm, salt-saturated water in a dark, silent tank, produces stronger altered states of consciousness—specifically a dissolving sense of body boundaries and distorted time perception—than simply lying on a waterbed in a dark, quiet room. In a crossover trial with 50 healthy adults, a 60-minute float session led to greater relaxation, less anxiety, and less tiredness compared to the control condition. The loss of body boundaries during floating directly contributed to the reduction in anxiety, pointing to a previously unknown mechanism behind floatation's calming effects.
Scientific reports
December 19, 2023
Antje Peters, Maximilian Bruchmann, Torge Dellert et al.
Inattentional numbness, the somatosensory equivalent of inattentional blindness or deafness, was studied with fMRI in 44 participants who received weak electrical stimulation on the left hand while performing a demanding visual task. Half were told the tactile stimuli would be above detection threshold, half below. Ten participants did not consciously perceive the stimuli. Prior information did not significantly affect awareness. Awareness of stimuli increased activation in the contralateral secondary somatosensory cortex but not in the primary somatosensory cortex or frontoparietal areas. The results suggest that somatosensory awareness relies on higher somatosensory cortex areas and does not require strong activation in extended anterior or posterior networks seen when stimuli are task-relevant.
Scientific reports
December 1, 2023
Amir Harduf, Gabriella Panishev, Eiran V Harel et al.
The sense of self is a core part of normal human consciousness, but it can be altered in psychiatric conditions like psychosis and in altered states induced by psychedelics. Using the Moving Rubber Hand Illusion with 75 participants—patients with psychosis, people with substantial psychedelic experience, and controls—the study tested how these experiences affect the bodily self. Psychosis patients showed reduced Body Ownership and Sense of Agency during voluntary movement. The psychedelic group reported long-lasting subjective changes to selfhood, but no differences from controls appeared on the bodily-self measures. Thus, while psychedelics alter the subjective sense of self, these changes do not manifest at the bodily level, whereas bodily self-processing linked to voluntary action is disrupted in psychosis.
Scientific reports
March 10, 2022
Anna Ciaunica, Luke McEllin, Julian Kiverstein et al.
During the COVID-19 lockdown, increased use of digital media and online social meetings correlated with higher feelings of depersonalisation—a sense of being detached from oneself, one's body, or the world. In a worldwide online study of 622 participants, those reporting more depersonalisation also reported enhanced vividness of negative emotions compared to positive ones. People whose lives were more affected by lockdown experienced depersonalisation more frequently. The findings suggest potential risks of overly sedentary, hyper-digitalised lifestyles that may induce feelings of living in one's 'head', disconnected from the body, self, and world.
Scientific reports
August 3, 2021
Amelia Dahlén, Mahdi Zarei, Adam Melgoza et al.
High doses of THC, a Cannabis constituent, increase psychosis risk in humans. Using adult zebrafish, which share a conserved endocannabinoid system with mammals, THC caused a concentration-dependent behavioral stereotypy, including distinctive circular swimming measured by a novel Repetition Index (RI). This RI was reduced by co-administration of the NMDA receptor agonist NMDA, suggesting THC's effects involve NMDA receptor antagonism. The GABA receptor antagonist pentylenetetrazol also reduced the RI. The cannabinoid receptor 1 inverse agonist AM251 did not reduce the behavior, while the cannabinoid receptor 2 inverse agonist AM630 significantly reduced it, pointing to cannabinoid receptor 2 as a possible mediator. The antipsychotic sulpiride also reduced the THC-induced RI. The model may help elucidate mechanisms linking Cannabis to psychosis.
Scientific reports
July 2, 2021
Carrie Cuttler, Emily M LaFrance, Amanda Stueber
Acute use of high-potency cannabis impairs memory and increases false memories, regardless of whether it contains CBD. In a study where 80 cannabis users either stayed sober or purchased and inhaled one of three high-potency products (flower with ≥20% THC without CBD, flower with ≥20% THC with CBD, or concentrates with ≥60% THC with CBD), all three cannabis products increased susceptibility to false memories. High-potency flower with CBD impaired free recall, while flower without CBD and concentrates impaired source memory. CBD did not offset cognitive impairments, and users self-titrated concentrates to produce comparable intoxication and impairment as flower.
Scientific reports
February 11, 2020
Ji-Min Lee, Pil-Jong Kim, Hong-Gee Kim et al.
Nitrous oxide administered at 50% for conscious sedation alters brain network connectivity in healthy adults. EEG recordings from 20 volunteers showed a steeper 1/f slope during sedation compared to baseline, indicating changes in brain network systems. Network connectivity parameters differed significantly in delta, alpha1, alpha2, and beta2 frequency bands, with the most pronounced functional distance changes in alpha1 and alpha2 bands. These alterations suggest nitrous oxide interferes with information integration in frequency bands important for cognitive processes and attention, which may relate to its sedative mechanism.
Scientific reports
October 4, 2018
Marion Quirins, Clémence Marois, Melanie Valente et al.
Pupil dilation is a reliable marker of conscious mental effort. In healthy volunteers, consciously detected violations of global auditory patterns triggered pupil dilation, whether participants actively counted or passively listened. This effect appeared at both group and individual levels. Unreported violations of global patterns, and local violations that do not require conscious awareness, produced no pupil dilation. The results were replicated with phonemes. Pupil dilation appears to be a somatic marker of conscious access in the auditory modality, offering a way to probe conscious processing without interrupting a person's stream of thought.