Trends in neurosciences
November 1, 1996
N Block
120 citations
The author argues that access consciousness and phenomenal consciousness, though conceptually distinct, might refer to the same brain process, similar to how water and H2O are different concepts of the same substance. However, recent work by Crick and Koch suggests that these two forms of consciousness may have distinct, albeit overlapping, neural correlates, even though Crick and Koch themselves implicitly reject this possibility.
Trends in neurosciences
November 1, 2024
Cecilia Anna Brunello, Cecilia Cannarozzo, Eero Castrén
29 citations
Antidepressant drugs, including slow-acting types, fast-acting ketamine, and psychedelics, all promote neuronal plasticity through activation of BDNF signaling via its receptor TRKB, though each drug targets different cells. The authors propose that some antidepressants may directly bind to TRKB and allosterically enhance BDNF signaling. Activating TRKB in parvalbumin-containing interneurons disinhibits cortical networks and reopens a juvenile-like window of plasticity. This rewiring of faulty neural circuits, combined with environmental input, may explain clinical antidepressant effects. This hypothesis could guide development of new treatments.
Trends in neurosciences
October 1, 2024
Natalia Zaretskaya
2 citations
Spontaneous brain activity before a stimulus influences whether it is consciously perceived. The prefrontal cortex and default mode network play active roles in shaping perception, not just in higher-level cognition. The findings suggest that prestimulus neural states in multiple brain networks modulate sensory processing and conscious awareness.
Trends in neurosciences
April 1, 2009
Javier González-Maeso, Stuart C Sealfon
Research on psychedelics like LSD and dissociative drugs such as PCP has converged with studies of schizophrenia, as their effects mimic core symptoms of the disorder. Some atypical antipsychotics were identified by their high affinity for serotonin 5-HT(2A) receptors, the same target as LSD-like drugs. Effects of PCP-like drugs are strongly influenced by modulation of both 5-HT(2A) and metabotropic glutamate 2/3 receptors. A serotonin-glutamate receptor complex in cortical pyramidal neurons may be the target of both psychedelics and certain antipsychotics. Recent findings on receptor, signaling, and circuit mechanisms could unify the serotonin and glutamate neurochemical hypotheses of schizophrenia.
Trends in neurosciences
June 1, 2001
F R Sharp, M Tomitaka, M Bernaudin et al.
Non-competitive NMDA receptor antagonists like phencyclidine, ketamine, and MK801 cause psychosis in humans and damage the cingulate-retrosplenial cortex in adult rodents. This damage can be prevented by GABA-receptor agonists and antipsychotics such as haloperidol and clozapine. Injecting MK801 into the anterior thalamus reproduces the cortical injury, while injecting GABA-receptor agonists there prevents injury from systemic MK801. The authors suggest that inhibiting NMDA receptors on GABAergic thalamic reticular nucleus neurons may activate thalamocortical circuits that cause injury in animals and psychosis in humans, potentially contributing to schizophrenia.