The Enlightened Mouse

The use of animal models as surrogates for humans in scientific experiments goes back centuries. If animals and humans aren’t that different, the thinking goes, we can learn about human biology by studying the biology of our mammalian relatives. According to “Of Mice and Mindfulness” (Reynolds, NY Times – Well, 18 May 2017), the animal model approach might even be used to learn how human brains respond to various mental states, including meditation.

Previous research on humans had revealed a positive correlation between meditation and the amount of white brain matter in a region of the human brain called the anterior cingulate cortex, a part of the brain involved in regulating emotions. Because humans lead such complicated lives, though, researchers could not say whether meditation caused this change in brain matter.

Enter the mouse.

Researchers at the University of Oregon have bred lab mice with a very special trait: some of their brain neurons are sensitive to light. Because these neurons respond to light signals, the researchers thought it might be possible to induce a meditative brain state in these mice by exposing the mice to light that oscillates on-off at the same frequency as the brain waves that appear in human meditators.

So far the researchers have reported (“Rhythmic brain stimulation reduces anxiety-related behavior in a mouse model based on meditation training” PNAS, 7 Mar 2017) that mice who were regularly exposed to very low frequency light oscillations of 1 Hz or 8 Hz (the latter is the same frequency as theta waves) displayed fewer behaviors associated with anxiety compared to mice who were not treated with light pulses and mice who were treated with higher frequency (40 Hz) oscillations.

While the researchers couldn’t ask the mice whether they were meditating or not, the behavioral changes are significant clues to their experience. Subsequent studies should be able to establish whether the “theta wave” light treatment also produces measurable changes in the mice brains.

Thanks, Robin, for passing this along.