Science Translational Medicine
August 14, 2013
Adenauer G. Casali, Olivia Gosseries, Mario Rosanova et al.
1,299 citations
A new index called the perturbational complexity index (PCI) can objectively measure a person's level of consciousness without requiring them to respond or interact. PCI works by using transcranial magnetic stimulation to briefly perturb the cortex and then measuring the algorithmic complexity of the resulting brain activity patterns. The index was tested on healthy individuals during wakefulness, dreaming, nonrapid eye movement sleep, and under sedation with midazolam, xenon, and propofol, as well as on patients who had emerged from coma. PCI reliably distinguished conscious from unconscious states in single individuals across all conditions, including vegetative state, minimally conscious state, and locked-in syndrome.
Science Translational Medicine
December 11, 2019
Boris D. Heifets, Juliana S. Salgado, Madison Taylor et al.
119 citations
MDMA's prosocial effects can be separated from its addictive properties by using fenfluramine, a selective serotonin-releasing compound. This finding reveals a conserved neuronal pathway that could be targeted to develop new therapeutics with limited abuse liability, offering a potential strategy for creating safer treatments that promote social connection without the risks of addiction.
Science Translational Medicine
January 10, 2024
Katie Kamenish, Roberto Arban, Aslihan Selimbeyoglu et al.
26 citations
Negative cognitive biases—where mood colors learning and memory—are a core feature of major depressive disorder, and reversing them may be key to how rapid-acting antidepressants work. In rats, a single dose of ketamine, scopolamine, or psilocybin selectively weakened a negative affective bias induced in an associative learning task. Low doses of ketamine and psilocybin, but not high doses, reversed the valence of the bias 24 hours later. Only psilocybin produced a lasting positive bias that depended on new learning. Ketamine's relearning effects required protein synthesis in the medial prefrontal cortex and could be altered by cue reactivation, pointing to experience-dependent neural plasticity as a shared mechanism for both the rapid and sustained effects of these drugs.
Science Translational Medicine
February 22, 2012
George A. Mashour
The psychedelic drug psilocybin disrupts the coordinated activity of important brain regions, which may help explain its potential for treating psychiatric disorders. This uncoupling of brain area activity offers clues for developing new therapies.