Dialogues in Clinical Neuroscience
March 31, 2014
Ronald S. Duman
248 citations
Stress and depression cause loss of synaptic connections in brain regions like the prefrontal cortex and hippocampus, partly through decreased brain-derived neurotrophic factor (BDNF). Typical antidepressants struggle to reverse these structural changes. Ketamine, an NMDA receptor antagonist, rapidly increases spine synapses in the prefrontal cortex and reverses chronic stress deficits in animal models, likely by disinhibiting glutamate transmission, boosting BDNF release, and activating synapse-forming pathways. Scopolamine, a muscarinic receptor antagonist, similarly increases glutamate transmission and synapse formation. These findings have led to testing of additional agents that influence glutamate transmission, showing rapid antidepressant effects in rodent models and clinical trials.
Dialogues in Clinical Neuroscience
June 30, 2019
David Nutt
131 citations
Classical psychedelic drugs like psilocybin and LSD, plus MDMA (ecstasy), were used extensively in psychiatric research before being prohibited. The ban stopped research and clinical treatments that had shown promise, though recreational use continued. In the past decade, groups have re-evaluated these substances in medicine. Preliminary data show promise for psilocybin in anxiety, depression, smoking, and alcoholism, and for MDMA in post-traumatic stress disorder and alcoholism. The European Medicines Agency approved psilocybin for a phase 3 study in treatment-resistant depression, and the FDA approved MDMA for PTSD. Results are expected in 2020; positive outcomes could lead to clinical approval soon after.
Dialogues in Clinical Neuroscience
December 31, 2001
Franz X. Vollenweider
127 citations
A review of brain imaging and behavioral studies finds that classic hallucinogens like psilocybin and dissociative anesthetics like ketamine produce overlapping psychotic syndromes marked by increased activity in the prefrontal cortex and changes in temporoparietal, striatal, and thalamic regions, suggesting a common final pathway. Both drug classes disrupt sensory gating in rats by acting on serotonin 5-HT(2) receptors in cortico-striato-thalamic circuitry, indicating that disruption of cortico-subcortical processing leading to sensory overload of the cortex is a shared feature of these psychoses. In contrast, the entactogen MDMA produces positive mood and activates prefrontolimbic and paralimbic structures while deactivating the amygdala and thalamus.
Dialogues in Clinical Neuroscience
September 30, 2009
Euphrosyne Gouzoulis‐mayfrank, Jörg Daumann
115 citations
High doses of MDMA (ecstasy) and stimulant amphetamines like methamphetamine (speed) are clearly neurotoxic in laboratory animals. MDMA selectively damages central serotonergic nerve terminals, while amphetamines harm both serotonergic and dopaminergic systems. In human drug users, evidence suggests residual alterations of serotonergic transmission from MDMA, with possible partial recovery after long-term abstinence, though functional impairments may persist. Subtle cognitive impairments, especially memory deficits, are the most consistent findings. For methamphetamine, preliminary evidence indicates dopaminergic system alterations may persist after years of abstinence, linked to motor and cognitive performance deficits.
Dialogues in Clinical Neuroscience
December 1, 2025
Ivona-Maria Tudorancea, Gabriela-Dumitrita Stanciu, Carla Torrent et al.
4 citations
As the global population ages, depression in older adults is increasingly common, yet conventional antidepressants often have limited effectiveness and problematic side effects. Psychedelic compounds are emerging as a potential alternative. This review examines preclinical and clinical evidence suggesting psychedelics could treat major depressive disorder in the elderly. It discusses the neurobiological mechanisms behind these effects, highlights relevant animal models, and addresses safety concerns. The authors propose strategies to improve the efficacy and safety of psychedelic therapy in future clinical trials, offering a new avenue for treating late-life depression.
Dialogues in Clinical Neuroscience
September 2, 2024
Shiven Chaudhry, Anne Weisman, Molly M. Hagen et al.
A two-hour team-based learning curriculum improved medical students' knowledge, comprehension, and ethical understanding of psychedelic therapies. Pre- and post-surveys from 63 and 50 students, respectively, showed significant gains in perceived knowledge and attitudes, while 48 matched pre/post-knowledge tests demonstrated enhanced comprehension. Qualitative feedback indicated greater comfort discussing psychedelics clinically, though some students expressed reservations about psychedelic-assisted therapy. The curriculum addresses an educational gap as psychedelic medicine becomes more relevant.
Dialogues in Clinical Neuroscience
December 1, 2025
Giulia Brizzi, Chiara Pupillo, Clara Rastelli et al.
A virtual reality simulation of a psychedelic experience, created by applying the Google DeepDream algorithm to a calming garden scene, enhanced cognitive flexibility and inhibitory control in healthy adults. Participants watched two 10-minute immersive VR videos: a standard garden and its hallucinated counterpart. After the hallucinatory video, they showed improved cognitive flexibility and reported greater absorption in the experience, though they found it less fluent. Both VR experiences reduced positive emotions, anxiety, heart rate, and sympathetic nervous system activity compared to before the videos. The combination of cognitive enhancement with a relaxed, awakened physiological state suggests such simulations might offer therapeutic benefits of psychedelics without their risks.
Dialogues in Clinical Neuroscience
May 20, 2024
L. Naccache, E. Munoz-Musat
A general model of Functional Neurological Disorders (FND) proposes that these disorders may arise from a consciously initiated voluntary top-down process that produces involuntary lasting consequences, which the patient then consciously experiences and interprets as involuntary. The model is developed within the Global Neuronal Workspace theory of consciousness, which describes interactions between conscious and non-conscious cognitive processes. A list of predictions for empirical testing is presented, and the model reinterprets the debated links between hypnotic suggestion and FND. The theoretical paper aims to bridge psychiatric and neurological perspectives on FND with advances in cognitive neuroscience of consciousness.
Dialogues in Clinical Neuroscience
March 1, 2012
Thomas Sturm
The mind-body problem, examined at the intersection of philosophy and neuroscience, centers on phenomenal consciousness or 'qualia.' Several skeptical arguments challenge the possibility of explaining qualia in purely physical terms: the knowledge argument, conceivability arguments, the multiple realizability argument, and the explanatory gap argument. None of these arguments proves very convincing, so reductive physicalism remains a defensible position, though not the only option. To avoid dogmatism and naivety, such a view requires ongoing conceptual and methodological reflection alongside empirical research.