Ketamine appears to be more effective as an antidepressant in mouse experiments if they are conducted by a male researcher, raising questions about other studies in mice

Life 8 September 2022

A researcher holding a mouse

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Laboratory mice tend to be more stressed when they can smell men, making them behave differently in experiments depending on whether they are handled by a man or a woman. The finding raises important questions about past research using mice, since animal studies generally don’t control for an experimenter’s sex.

Todd Gould at the University of Maryland began investigating this issue after his team couldn’t replicate a simple lab result. The experiment involved a “forced swim test”, in which researchers place mice in …