Consciousness is known to be limited in processing capacity and often described in terms of a unique processing stream across a single dimension: time. In this paper, we discuss a purely temporal pattern code, functionally decoupled from spatial signals, for conscious state generation in the brain. Arguments in favour of such a code include Dehaene et al.'s long-distance reverberation...
BACKGROUND: Major depression has the highest rate of prevalence and incidence of morbidity among all mental disoders. The limited efficacies of current antidepressant treatments necessitate the development of alternative pharmacotherapies. Recent preclinical findings suggesting that cannabinoid CB(1) receptor agonists and endocannabinoid enhancers possess antidepressant-like properties, and...
Few and often contradictory reports exist on the long-term neurobiological consequences of cannabinoid consumption in adolescents. The endocannabinoid system plays an important role during the different stages of brain development as cannabinoids influence the release and action of different neurotransmitters and promote neurogenesis. This study tested whether long-lasting interference by...
Neuroscience LettersAugust 22, 2008Shanker Jha, Rajeev Rajendran, Kimberly A Fernandes et al.
Adult hippocampal neurogenesis is reported to be a target of antidepressants, drugs of abuse and animal models of depression, suggesting a role for this form of structural plasticity in psychopathology. Serotonergic neurotransmission, which is implicated in several psychiatric diseases, has been reported to regulate adult hippocampal neurogenesis. Amongst the serotonergic receptors, the...
The endocannabinoid system modulates neurotransmission at inhibitory and excitatory synapses in brain regions relevant to the regulation of pain, emotion, motivation, and cognition. This signaling system is engaged by the active component of cannabis, Δ9-tetrahydrocannabinol (Δ9-THC), which exerts its pharmacological effects by activation of G protein-coupled type-1 (CB1) and type-2 (CB2)...
This article develops the Synchronous Matching Adaptive Resonance Theory (SMART) neural model to explain how the brain may coordinate multiple levels of thalamocortical and corticocortical processing to rapidly learn, and stably remember, important information about a changing world. The model clarifies how bottom-up and top-down processes work together to realize this goal, notably how...
Because of the prominent psychoactive effects of cannabis and its preparations, much research has focused on the actions of cannabinoids, the primary psychoactive components of cannabis, on neuronal function. A convergence of research has identified (1) cannabinoid receptors, (2) endogenous compounds that activate these receptors (endocannabinoids), and (3) drugs that interact with these...
Evidence exists that schizophrenia is characterized by deficits in cell-cell communication and information processing. In the present study, we used the phencyclidine (PCP) animal model of schizophrenia to investigate possible defects in intracellular signaling proteins involved in neuroplasticity. Western Blot analysis has been performed to determine total and phospho-protein levels of...
Les cannabinoïdes contenus dans la plante de cannabis ont un double usage et possèdent des propriétés opposées suivant les circonstances et les doses employées. Les cannabinoïdes, essentiellement drogue récréative ou d'abus pourraient, pour certains d'entre eux, devenir des médicaments. Selon les conditions d'utilisation, ils peuvent être neurotoxiques ou neuroprotecteurs, carcinogènes ou...
Recent evidence indicates that the polysialylated neural cell adhesion molecule (PSA-NCAM) is involved in hippocampal plasticity. On the other hand, CB1 receptor activation is known to disturb some hippocampal processes involving plastic changes, such as learning and memory. Therefore, the present study investigated the effect of HU-210, a CB1 receptor agonist, on the expression of PSA-NCAM...