Journal of Neuroscience
April 6, 2011
Fadel Zeidan, Katherine T. Martucci, Robert A Kraft et al.
The subjective experience of one's environment is constructed by interactions among sensory, cognitive, and affective processes. For centuries, meditation has been thought to influence such processes by enabling a nonevaluative representation of sensory events. To better understand how meditation influences the sensory experience, we used arterial spin labeling functional magnetic resonance...
Journal of Neuroscience
March 23, 2011
Carlo Sestieri, Maurizio Corbetta, Gian Luca Romani et al.
545 citations
The default mode network (DMN) is often considered a functionally homogeneous system that is broadly associated with internally directed cognition (e.g., episodic memory, theory of mind, self-evaluation). However, few studies have examined how this network interacts with other networks during putative "default" processes such as episodic memory retrieval. Using functional magnetic resonance...
Journal of Neuroscience
March 2, 2011
Robert Leech, Salwa Kamourieh, Christian Beckmann et al.
801 citations
The posterior cingulate cortex (PCC) is a central part of the default mode network (DMN) and part of the structural core of the brain. Although the PCC often shows consistent deactivation when attention is focused on external events, anatomical studies show that the region is not homogeneous, and electrophysiological recordings in nonhuman primates suggest that it is directly involved in some...
Journal of Neuroscience
February 2, 2011
José L. Moreno, Mitsumasa Kurita, Terrell Holloway et al.
122 citations
Epidemiological studies indicate that maternal influenza viral infection increases the risk for schizophrenia in the adult offspring. The serotonin and glutamate systems are suspected in the etiology of schizophrenia, as well as in the mechanism of action of antipsychotic drugs. The effects of hallucinogens, such as psilocybin and mescaline, require the serotonin 5-HT 2A receptor, and induce...
Journal of Neuroscience
January 26, 2011
Lucia Melloni, Caspar M Schwiedrzik, Notger G Müller et al.
Previous experience allows the brain to predict what comes next. How these expectations affect conscious experience is poorly understood. In particular, it is unknown whether and when expectations interact with sensory evidence in granting access to conscious perception, and how this is reflected electrophysiologically. Here, we parametrically manipulate sensory evidence and expectations while...
Journal of Neuroscience
October 6, 2010
Cullen L. Schmid, Laura M Bohn
172 citations
Hallucinogens mediate many of their psychoactive effects by activating serotonin 2A receptors (5-HT 2A R). Although serotonin is the cognate endogenous neurotransmitter and is not considered hallucinogenic, metabolites of serotonin also have high affinity at 5-HT 2A R and can induce hallucinations in humans. Here we report that serotonin differs from the psychoactive N -methyltryptamines by its...
Journal of Neuroscience
August 25, 2010
Silvia Sorce, Stefania Schiavone, Paolo Tucci et al.
Subanesthetic doses of NMDA receptor antagonist ketamine induce schizophrenia-like symptoms in humans and behavioral changes in rodents. Subchronic administration of ketamine leads to loss of parvalbumin-positive interneurons through reactive oxygen species (ROS), generated by the NADPH oxidase NOX2. However, ketamine induces very rapid alterations, in both mice and humans. Thus, we have...
Journal of Neuroscience
July 28, 2010
Claudio Acuna-Goycolea, Karl Obrietan, Anthony N Van den Pol
Cannabinoids, the primary active agent in drugs of abuse such as marijuana and hashish, tend to generate a distorted sense of time. Here we study the effect of cannabinoids on the brain's circadian clock, the suprachiasmatic nucleus (SCN), using patch clamp and cell-attached electrophysiological recordings, RT-PCR, immunocytochemistry, and behavioral analysis. The SCN showed strong expression...
Journal of Neuroscience
July 28, 2010
Jayna M. Amting, Steven G. Greening, Derek G. V. Mitchell
Emotional stimuli, including facial expressions, are thought to gain rapid and privileged access to processing resources in the brain. Despite this access, we are conscious of only a fraction of the myriad of emotion-related cues we face everyday. It remains unclear, therefore, what the relationship is between activity in neural regions associated with emotional representation and the...
Journal of Neuroscience
June 9, 2010
Cameron H Good, Carl R. Lupica
Ventral tegmental area (VTA) dopamine (DA) neurons play a pivotal role in processing reward-related information and are involved in drug addiction and mental illness in humans. Information is conveyed to the VTA in large part by glutamatergic afferents that arise in various brain nuclei, including the pedunculopontine nucleus (PPN). Using a unique rat brain slice preparation, we found that PPN...
Journal of Neuroscience
March 17, 2010
Simon van Gaal, K Richard Ridderinkhof, H Steven Scholte et al.
Cognitive control processes involving prefrontal cortex allow humans to overrule and inhibit habitual responses to optimize performance in new and challenging situations, and traditional views hold that cognitive control is tightly linked with consciousness. We used functional magnetic resonance imaging to investigate to what extent unconscious "no-go" stimuli are capable of reaching cortical...
Journal of Neuroscience
November 18, 2009
Angela R. Laird, Simon B. Eickhoff, Karl Li et al.
577 citations
The default mode network (DMN) comprises a set of regions that exhibit ongoing, intrinsic activity in the resting state and task-related decreases in activity across a range of paradigms. However, DMN regions have also been reported as task-related increases, either independently or coactivated with other regions in the network. Cognitive subtractions and the use of low-level baseline...
Journal of Neuroscience
October 21, 2009
Antoine Lutz, Heleen A. Slagter, Nancy B. Rawlings et al.
499 citations
The capacity to stabilize the content of attention over time varies among individuals, and its impairment is a hallmark of several mental illnesses. Impairments in sustained attention in patients with attention disorders have been associated with increased trial-to-trial variability in reaction time and event-related potential deficits during attention tasks. At present, it is unclear whether...
Journal of Neuroscience
September 1, 2009
Kurt E Weaver, Andrew G Richardson
The medial prefrontal cortex (mPFC), which encompasses the anterior paracingulate cortex and extends rostrally along the medial frontal wall, has recently received a considerable amount of scientific inquiry as a distinct subregion of the frontal lobe. This is, in part, because the mPFC is involved
Journal of Neuroscience
June 3, 2009
Atheir I. Abbas, Prem N. Yadav, Wei-Dong Yao et al.
131 citations
Here, we report that postsynaptic density protein of 95 kDa (PSD-95), a postsynaptic density scaffolding protein, classically conceptualized as being essential for the regulation of ionotropic glutamatergic signaling at the postsynaptic membrane, plays an unanticipated and essential role in mediating the actions of hallucinogens and atypical antipsychotic drugs at 5-HT 2A and 5-HT 2C...
Journal of Neuroscience
October 1, 2008
Martijn Van den Heuvel, René Mandl, Judith Luigjes et al.
The default mode network is a functionally connected network of brain regions that show highly synchronized intrinsic neuronal activation during rest. However, less is known about the structural connections of this network, which could play an important role in the observed functional connectivity patterns. In this study, we examined the microstructural organization of the cingulum tract in...
Journal of Neuroscience
June 1, 2008
Individual differences in psychotic effects of ketamine are predicted by brain function measured under placebo.
Journal of Neuroscience
May 14, 2008
Wulf Hevers, Stephen H Hadley, Hartmut Lüddens et al.
Phencyclidine (PCP) and ketamine are dissociative anesthetics capable of inducing analgesia, psychomimetic behavior, and a catatonic state of unconsciousness. Despite broad similarities, there are notable differences between the clinical actions of ketamine and PCP. Ketamine has a lower incidence of adverse effects and generally produces greater CNS depression than PCP. Both noncompetitively...
Journal of Neuroscience
March 12, 2008
Stéphane Doly, Emmanuel Valjent, Vincent Setola et al.
140 citations
The “club drug” 3,4-methylenedioxymethamphetamine (MDMA; also known as ecstasy) binds preferentially to and reverses the activity of the serotonin transporter, causing release of serotonin [5-hydroxytryptamine (5-HT)] stores from nerve terminals. Subsequent activation of postsynaptic 5-HT receptors by released 5-HT has been shown to be critical for the unique psychostimulatory effects of MDMA....
Journal of Neuroscience
March 5, 2008
K. Phan, Mike Angstadt, J. Golden et al.
The cannabinoid (CB) system is a key neurochemical mediator of anxiety and fear learning in both animals and humans. The anxiolytic effects of Δ9-tetrahydrocannabinol (THC), the primary psychoactive ingredient in cannabis, are believed to be mediated through direct and selective agonism of CB1 receptors localized within the basolateral amygdala, a critical brain region for threat perception....
Journal of Neuroscience
October 24, 2007
Francis Rodriguez Bambico, Noam Katz, Guy Debonnel et al.
325 citations
Preclinical and clinical studies show that cannabis modulates mood and possesses antidepressant-like properties, mediated by the agonistic activity of cannabinoids on central CB1 receptors (CB1Rs). The action of CB1R agonists on the serotonin (5-HT) system, the major transmitter system involved in mood control and implicated in the mechanism of action of antidepressants, remains however poorly...
Journal of Neuroscience
January 4, 2006
Joseph M. Breier, Michael G. Bankson, Bryan K. Yamamoto
The specific mechanisms underlying (+)-3,4-methylenedioxymethamphetamine (MDMA)-induced damage to 5-HT terminals are unknown. Despite the hypothesized role for dopamine (DA) and DA-derived free radicals in mediating this damage, it remains unclear why MDMA produces long-term depletions of 5-HT in brain regions that are sparsely innervated by DA neurons. We hypothesized that the precursor to DA...
Journal of Neuroscience
December 14, 2005
Susana Mato, David Robbe, Nagore Puente et al.
Alterations of long-term synaptic plasticity have been proposed to participate in the development of addiction. To preserve synaptic functions, homeostatic processes must be engaged after exposure to abused drugs. At the mouse cortico-accumbens synapses, a single in vivo injection of Delta9-tetrahydrocannabinol (THC) suppresses endocannabinoid-mediated long-term depression. Using biochemical...
Journal of Neuroscience
May 1, 2005
Satu Palva, Klaus Linkenkaer-Hansen, Risto Näätänen et al.
The cortical processing of consciously perceived and unperceived somatosensory stimuli is thought to be identical during the first 100-120 ms after stimulus onset. Thereafter, the electrophysiological correlates of conscious perception have been shown to be reflected in the N1 component of the evoked response as well as in later (>200 ms) nonstimulus-locked gamma-band (28-50 Hz) oscillatory...
Journal of Neuroscience
January 19, 2005
Olaf Blanke, Christine Mohr, Christoph M. Michel et al.
573 citations
The spatial unity of self and body is challenged by various philosophical considerations and several phenomena, perhaps most notoriously the "out-of-body experience" (OBE) during which one's visual perspective and one's self are experienced to have departed from their habitual position within one's body. Although researchers started examining isolated aspects of the self, the neurocognitive...