For example, in a new mouse-based study published in Science Advances, researchers have described a puzzling result: Ketamine anesthesia causes a remodeling of brain tissues – but only in females. About an hour after ketamine administration, microglia started establishing significantly more contact with neurons in the brains of female mice. In a previous study, researchers found that ketamine anesthesia induced anxiety traits – but, again, only in female mice. "There were only a handful of anecdotal studies showing that women experience nausea and sickness more often after ketamine anesthesia," Siegert notes. asks Bosiljka Tasic, a neurobiologist at the Allen Institute for Brain Science in Seattle and one of the study's co-authors.