PLoS Biology
May 4, 2007
Heleen A. Slagter, Antoine Lutz, Lawrence L. Greischar et al.
762 citations
Intensive meditation training reduces the attentional blink—a phenomenon where a second target in a rapid stream is often missed when it appears shortly after a first target. Three months of daily mental practice led to a smaller attentional blink and decreased brain-resource allocation to the first target, measured by a smaller P3b brain potential. Individuals with the largest reduction in resource allocation to the first target showed the greatest improvement in detecting the second target. These findings indicate that mental training enhances control over limited attentional resources and supports lifelong brain plasticity.
PLoS Biology
July 9, 2015
Xavier Viñals, Estefanía Moreno, Laurence Lanfumey et al.
211 citations
Activation of cannabinoid CB1 receptors (CB1R) by delta9-tetrahydrocannabinol (THC) causes negative effects including memory deficits, limiting therapeutic use. Behavioral studies in mice lacking 5-HT2A receptors (5-HT2AR) showed a dissociation: THC's antinociceptive effects remained, but its amnesic, anxiolytic-like, and social interaction effects depended on 5-HT2AR, while hypolocomotor, hypothermic, anxiogenic, and antinociceptive effects did not. Biochemical studies revealed CB1R and 5-HT2AR form heteromers in brain regions involved in memory, altering cell signaling and G-protein coupling. Synthetic peptides disrupting heteromerization selectively prevented THC-induced memory impairments, identifying CB1R-5-HT2AR heteromers as targets to separate cognitive deficits from beneficial pain relief.
PLoS Biology
January 27, 2015
David Nutt
66 citations
The United Nations drug control conventions from 1960 and 1971, along with later additions, have inadvertently created major restrictions on medical and life sciences research. These conventions need revision to allow neuroscience to advance without hindrance and to support innovation in treatments for brain disorders. In the interim, local changes like the United Kingdom reclassifying cannabis from Schedule 1 to Schedule 2 should be implemented to enable appropriate medical research development.
PLoS Biology
October 1, 2025
Michele Angelo Colombo, Jacopo Favaro, Ezequiel Mikulan et al.
7 citations
After hemispherotomy surgery for epilepsy, which disconnects an entire brain hemisphere, the isolated cortex shows brainwave patterns typical of deep sleep or anesthesia, not wakefulness. In 10 pediatric patients, EEG recordings revealed prominent slow oscillations and a steeper spectral decay in the disconnected hemisphere, while the connected hemisphere maintained normal waking patterns. These sleep-like patterns persisted years after surgery, suggesting the isolated cortex likely lacks awareness.
PLoS Biology
July 1, 2025
Angus Leung, Ahmed A Mahmoud, Travis Jeans et al.
3 citations
Only 47 out of over 7,700 time-series features reliably distinguished wakefulness from anesthesia or sleep across all evaluation groups of flies. Most of these features were related to autocorrelation, indicating that signals during wakefulness remained correlated to their past for longer than during anesthesia or sleep. Features related to complexity or spectral power, often proposed as consciousness markers, failed to generalize across all datasets, though many showed consistent direction of effect. These results caution that many newly discovered potential consciousness markers may not generalize across datasets, and point to autocorrelation as a class of dynamical properties that does.
PLoS Biology
July 1, 2025
Simon van Gaal
1 citation
A new pre-registered study in PLOS Biology compares several proposed neuronal markers of loss of consciousness in flies across three global brain states: awake, asleep, and anesthetized. The work evaluates which neural markers can differentiate these states, testing markers previously suggested to underlie states of consciousness. The findings indicate which markers reliably distinguish between wakefulness, sleep, and anesthesia in the fly model.
PLoS Biology
July 6, 2026
Maëlan Q. Menétrey, Michael H Herzog, David Pascucci
In the Sequential Metacontrast (SQM) paradigm, later visual stimuli alter the perception of earlier ones, indicating that conscious perception can follow extended unconscious processing. Using EEG recordings in humans, researchers identified two distinct neural activity stages: an early occipital pattern around 200 milliseconds after the initial vernier, linked to unconscious processing, and a later centro-parietal pattern between 400 and 600 milliseconds after SQM onset, associated with the integrated percept and behavioral report. The transition between these patterns marks the shift from unconscious encoding of individual visual stimuli to their integrated conscious percept.
PLoS Biology
March 1, 2026
Adriana Michalak, Davide Marzoli, Francesco Pietrogiacomi et al.
Perceived sleep depth, a key part of subjective sleep quality, is traditionally linked to unconsciousness and reduced brain activity. Combining high-density EEG with a serial awakening paradigm during N2 sleep in healthy participants, the study found that deeper sleep was associated with a lower high-to-low frequency power ratio, indicating reduced cortical activation. However, this relationship weakened when dreaming occurred, suggesting immersive conscious experiences can counteract the impact of cortical activation on perceived depth. Perceived sleep depth was lowest during minimal awareness (a mere sense of presence) and highest during immersive dreaming or deep unconsciousness.
PLoS Biology
May 1, 2021
Timo Stein, Daniel Kaiser, Johannes J Fahrenfort et al.
How unconscious processing is measured—either by asking participants what they saw (subjective) or by testing whether they can discriminate stimuli (objective)—affects conclusions about the brain's representation of unseen information. Using fMRI in 43 people viewing masked faces and houses that were either subjectively or objectively invisible, category information was found in early and higher visual cortex even for objectively invisible stimuli, though representations in anterior ventrotemporal areas were weaker. For subjectively invisible stimuli, a clear posterior-to-anterior gradient appeared, with stronger category information in ventrotemporal cortex. For objectively invisible stimuli, category information remained similar across visual areas. The measurement approach thus influences the extent of unconscious processing and the neural correlates of consciousness.
PLoS Biology
February 1, 2019
M. Kohda, Takashi Hotta, Tomohiro Takeyama et al.
A fish, the cleaner wrasse, shows behaviors that may be interpreted as passing the mark test for mirror self-recognition, a cognitive ability previously known only in mammals and birds. When given a colored tag, the fish scrapes their body in front of a mirror to remove it but does not respond to transparent marks or to colored marks without a mirror. The finding challenges whether these behaviors indicate self-awareness in fish or reflect a different cognitive process, raising questions about the mark test's validity across species.
PLoS Biology
June 15, 2016
Stanislas Dehaene, Jean-Pierre Changeux
Even without sensory input, cortical and thalamic neurons exhibit structured spontaneous activity whose origins and functions are unclear. Computer simulations of a simplified model with multiple interconnected thalamocortical columns and long-range excitatory axons reveal two main activity states: spontaneous gamma-band oscillations emerge at a precise threshold controlled by neuromodulator systems, and within a spontaneously active network, sudden "ignition" of one of many possible coherent high-level activity states occurs among cortical neurons with long-distance projections. During ignition, spontaneous activity can block external sensory processing, relating to inattentional blindness, where intensely engaged subjects fail to notice salient but irrelevant stimuli. The minimal network's generic properties may clarify basic cerebral phenomena underlying consciousness's autonomy.