Mice that were exposed to heavy metal became aggressive and murderous

One study conducted by David Merrill exposed mice to heavy metal 24 hours a day. The band chosen was Anthrax. The purpose of the study was to see how the heavy metal would affect their ability to learn new things.

Shockingly, the experiment could not be finished because instead of completing the Maze, the heavy metal mice all killed each other.
In further experiments, Merrill exposed the mice to heavy metal for only 10 hours a day. Even though the mice did not become homicidal in this experiment, they were much worse at solving the maze than when they had first encountered it.

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