Neuroimage
July 1, 2019
Lucie Bréchet, Denis Brunet, Gwénaël Birot et al.
The temporal structure of self-generated cognition is a key attribute to the formation of a meaningful stream of consciousness. When at rest, our mind wanders from thought to thought in distinct mental states. Despite the marked importance of ongoing mental processes, it is challenging to capture and relate these states to specific cognitive contents. In this work, we employed ultra-high field...
Neuroimage
June 24, 2019
Carla Pallavicini, Martina G. Vilas, Mirta Villarreal et al.
66 citations
Classic serotonergic psychedelics are remarkable for their capacity to induce reversible alterations in consciousness of the self and the surroundings, mediated by agonism at serotonin 5-HT2A receptors. The subjective effects elicited by dissociative drugs acting as N-methyl-D-aspartate (NMDA) antagonists (e.g. ketamine and phencyclidine) overlap in certain domains with those of serotonergic...
Neuroimage
May 25, 2019
Louis-David Lord, Paul Expert, Selen Atasoy et al.
249 citations
Growing evidence from the dynamical analysis of functional neuroimaging data suggests that brain function can be understood as the exploration of a repertoire of metastable connectivity patterns ('functional brain networks'), which potentially underlie different mental processes. The present study characterizes how the brain's dynamical exploration of resting-state networks is rapidly modulated...
Neuroimage
May 15, 2019
Léa M Martinon, Jonathan Smallwood, Deborah McGann et al.
Human cognition is not limited to the processing of events in the external environment, and the covert nature of certain aspects of the stream of consciousness (e.g. experiences such as mind-wandering) provides a methodological challenge. Although research has shown that we spend a substantial amount of time focused on thoughts and feelings that are intrinsically generated, evaluating such...
Neuroimage
April 5, 2019
Duan Li, George A. Mashour
103 citations
Ketamine is a unique drug that has psychedelic and anesthetic properties in a dose-dependent manner. Recent studies have shown that ketamine anesthesia appears to maintain the spatiotemporal complexity of cortical activation evoked by transcranial magnetic stimulation, while a psychedelic dose of ketamine is associated with increased spontaneous magnetoencephalographic signal diversity....
Neuroimage
April 4, 2019
Ottavia Dipasquale, Pierluigi Selvaggi, Mattia Veronese et al.
79 citations
One of the main limitations of pharmacological fMRI is its inability to provide a molecular insight into the main effect of compounds, leaving an open question about the relationship between drug effects and haemodynamic response. The aim of this study is to investigate the acute effects of 3,4-methylenedioxymethamphetamine (MDMA) on functional connectivity (FC) using a novel multimodal method...
Neuroimage
March 1, 2019
Heonsoo Lee, Daniel Golkowski, Denis Jordan et al.
ABSTRACT Recent modeling and empirical studies support the hypothesis that large‐scale brain networks function near a critical state. Similar functional connectivity patterns derived from resting state empirical data and brain network models at criticality provide further support. However, despite the strong implication of a relationship, there has been no principled explanation of how...
Neuroimage
January 11, 2019
Michele A. Colombo, Martino Napolitani, Melanie Boly et al.
359 citations
Despite the absence of responsiveness during anesthesia, conscious experience may persist. However, reliable, easily acquirable and interpretable neurophysiological markers of the presence of consciousness in unresponsive states are still missing. A promising marker is based on the decay-rate of the power spectral density (PSD) of the resting EEG. We acquired resting electroencephalogram (EEG)...
Neuroimage
December 1, 2018
Tomer Fekete, D. Omer, Kazunori O’Hashi et al.
&NA; Critical dynamics are thought to play an important role in neuronal information‐processing: near critical networks exhibit neuronal avalanches, cascades of spatiotemporal activity that are scale‐free, and are considered to enhance information capacity and transfer. However, the exact relationship between criticality, awareness, and information integration remains unclear. To characterize...
Neuroimage
September 1, 2018
Christine Blume, Renata Del Giudice, Malgorzata Wislowska et al.
While it is a well-established finding that subjects' own names (SON) and familiar voices are salient during wakefulness, we here investigated processing of environmental stimuli during sleep including deep N3 and REM sleep. Besides the effects of sleep depth we investigated how sleep-specific EEG patterns (i.e. sleep spindles and slow oscillations [SOs]) relate to stimulus processing. Using...
Neuroimage
July 7, 2018
Tammi R. A. Kral, Brianna S. Schuyler, Jeanette A. Mumford et al.
ABSTRACT Meditation training can improve mood and emotion regulation, yet the neural mechanisms of these affective changes have yet to be fully elucidated. We evaluated the impact of long‐ and short‐term mindfulness meditation training on the amygdala response to emotional pictures in a healthy, non‐clinical population of adults using blood‐oxygen level dependent functional magnetic resonance...
Neuroimage
July 1, 2018
Qihong Zou, Shuqin Zhou, Jing Xu et al.
Rapid eye movement (REM) sleep has been frequently associated with dreaming. However, mounting evidence obtained from behavioral, pharmacological, and brain imaging studies suggests that REM sleep is not indicative of the dream report and may originate from diverse neural substrates in brain functionality. The aim of the current study was to investigate the functional systems associated with...
Neuroimage
June 9, 2018
S. Prashad, Elizabeth S. Dedrick, F. Filbey
&NA; Studies have shown altered task‐based brain functioning as a result of cannabis use. To date, however, whether similar alterations in baseline resting state and functional organization of neural activity are observable in cannabis users remains unknown. We characterized global resting state cortical activations and functional connectivity via electroencephalography (EEG) in cannabis users...
Neuroimage
May 15, 2018
Otto Muzik, Kaice T Reilly, Vaibhav A. Diwadkar
The defense of body temperature against environmental thermal challenges is a core objective of homeostatic regulation governed by the autonomic nervous system. Autonomous mechanisms of thermoregulation are only weakly affected by top-down modulation, allowing only transient tolerance for extreme cold. There is however, anecdotal evidence of a unique set of individuals known for extreme cold...
Neuroimage
May 1, 2018
Gregor Wilbertz, Madhura Ketkar, Matthias Guggenmos et al.
The phenomenon of bistable perception, in which perception alternates spontaneously despite constant sensory stimulation, has been particularly useful in probing the neural bases of conscious perception. The study of such bistability requires access to the observer's perceptual dynamics, which is usually achieved via active report. This report, however, constitutes a confounding factor in the...
Neuroimage
April 1, 2018
Ezequiel Mikulan, Eugenia Hesse, Lucas Sedeño et al.
Neural synchrony in the γ-band is considered a fundamental process in cortical computation and communication and it has also been proposed as a crucial correlate of consciousness. However, the latter claim remains inconclusive, mainly due to methodological limitations, such as the spectral constraints of scalp-level electroencephalographic recordings or volume-conduction confounds. Here, we...
Neuroimage
February 15, 2018
Michał Bola, Adam B. Barrett, Andrea Pigorini et al.
Loss of consciousness can result from a wide range of causes, including natural sleep and pharmacologically induced anesthesia. Important insights might thus come from identifying neuronal mechanisms of loss and re-emergence of consciousness independent of a specific manipulation. Therefore, to seek neuronal signatures of loss of consciousness common to sleep and anesthesia we analyzed...
Neuroimage
January 12, 2018
Charlotte Murphy, Elizabeth Jefferies, Shirley-Ann Rueschemeyer et al.
288 citations
The default mode network supports a variety of mental operations such as semantic processing, episodic memory retrieval, mental time travel and mind-wandering, yet the commonalities between these functions remains unclear. One possibility is that this system supports cognition that is independent of the immediate environment; alternatively or additionally, it might support higher-order...
Neuroimage
October 3, 2017
Federico Cavanna, Martina G. Vilas, Matías Palmucci et al.
151 citations
The scientific study of human consciousness has greatly benefited from the development of non-invasive brain imaging methods. The quest to identify the neural correlates of consciousness combined psychophysical experimentation with neuroimaging tools such as functional magnetic resonance imaging (fMRI) to map the changes in neural activity associated with conscious vs. unconscious percepts....
Neuroimage
September 1, 2017
Remko Van Lutterveld, Edwin Van Dellen, Prasanta Pal et al.
85 citations
This study aims to identify novel quantitative EEG measures associated with mindfulness meditation. As there is some evidence that meditation is associated with higher integration of brain networks, we focused on EEG measures of network integration. Sixteen novice meditators and sixteen experienced meditators participated in the study. Novice meditators performed a basic meditation practice...
Neuroimage
July 12, 2017
Candace R. Lewis, Katrin H. Preller, Rainer Kraehenmann et al.
105 citations
Psilocybin, the active compound in psychedelic mushrooms, is an agonist of various serotonin receptors. Seminal psilocybin positron emission tomography (PET) research suggested regional increases in glucose metabolism in frontal cortex (hyperfrontality). However, a recent arterial spin labeling (ASL) study suggests psilocybin may lead to hypo-perfusion in various brain regions. In this...
Neuroimage
January 18, 2017
Hannah J. Scheibner, Carsten Bogler, Tobias Gleich et al.
136 citations
Focused attention meditations have been shown to improve psychological health and wellbeing and are nowadays an integral part of many psychotherapies. While research on the neural correlates of focused attention meditation is increasing, findings vary on whether meditations are associated with high or low activity in the default mode network (DMN). To clarify the relationship between focused...
Neuroimage
2017
Lucie Charles, Raphaël Gaillard, Isabelle Amado et al.
The ability to detect our own errors is an essential component of action monitoring. Using a masking paradigm in normal adults, we recently discovered that some error-detection processes can proceed without awareness, while other markers of performance monitoring such as the Error-Related Negativity (ERN) are tightly linked to conscious perception. Interestingly, research on cognitive deficit...
Neuroimage
July 15, 2016
Aviva Berkovich-Ohana, Michal Harel, Avital Hahamy et al.
Recently we proposed that the information contained in spontaneously emerging (resting-state) fluctuations may reflect individually unique neuro-cognitive traits. One prediction of this conjecture, termed the "spontaneous trait reactivation" (STR) hypothesis, is that resting-state activity patterns could be diagnostic of unique personalities, talents and life-styles of individuals. Long-term...
Neuroimage
July 1, 2016
Anselm Doll, Britta K. Hölzel, Satja Mulej Bratec et al.
Mindfulness practice is beneficial for emotion regulation; however, the neural mechanisms underlying this effect are poorly understood. The current study focuses on effects of attention-to-breath (ATB) as a basic mindfulness practice on aversive emotions at behavioral and brain levels. A key finding across different emotion regulation strategies is the modulation of amygdala and prefrontal...