People often describe anesthesia as something that puts a patient in a “deep sleep.” An anesthesiologist enters the operating room, and part of their mission is to ensure that the patient is completely unaware of what is happening around them until they wake up, often several hours later. Scientists and doctors have long debated what happens to the brain under anesthetic drugs during a surgical procedure.

A new study by Yale School of Medicine’s Departments of Anesthesiology and Neurology published on May 11, 2026, in Proceedings of the National Academy of Sciences uncovers new insights which may change the way we describe being under anesthesia. The study, “Spectral mapping reveals a resemblance of the anesthetic brain state to both sleep and coma,” reveals that being anesthetized may be more than simply being “put to sleep.” It can potentially carry more similarities to being in a coma than we originally thought.

Zhou et al. demonstrate that perineural invasion (PNI) is an adverse prognostic factor in small cell lung cancer. They identify a neuron-STMN2-β-alanine axis, where the neural microenvironment upregulates STMN2 in tumor cells, reprogramming β-alanine metabolism to enhance cell migration and drive neural invasion, revealing a potential therapeutic target.

Myelination is increasingly recognized as a dynamic and adaptive process regulated by oligodendrocytes throughout life. Beyond providing electrical insulation, myelin supports axonal metabolism and may serve as an energy reservoir under metabolic stress, highlighting the importance of physiological myelin turnover. Dysregulation of myelin dynamics contributes to a wide spectrum of neurological disorders, including demyelinating, neurodegenerative, and neuropsychiatric diseases. Growing evidence indicates that neurotransmitter signaling through G protein-coupled receptors (GPCRs) expressed by oligodendrocyte lineage cells regulates myelin formation, remodeling, and repair.

Li et al. use multimodal MRI to show that cerebral blood volume is inversely correlated with glymphatic influx across six brain states. Lower CBV is associated with expanded extra-ventricular CSF space, and caffeine produces a similar pattern in awake mice, suggesting CBV as a tonic vascular factor complementing pulsation and vasomotion.

Glioblastoma (GBM) is the most common and aggressive malignant brain tumor. Standard treatments including surgical resection, radiotherapy, and chemotherapy, have failed to significantly improve the prognosis of glioblastoma patients. Currently, immunotherapeutic approaches based on vaccines, chimeric antigen-receptor T-cells, checkpoint inhibitors, and oncolytic virotherapy are showing promising results in clinical trials. The combination of different immunotherapeutic approaches is proving satisfactory and promising. In view of the challenges of immunotherapy and the resistance of glioblastomas, the treatment of these tumors requires further efforts. In this review, we explore the obstacles that potentially influence the efficacy of the response to immunotherapy and that should be taken into account in clinical trials.