The beneficial effects of light on our ability to think is well documented, but American boffins think they may now have discovered the neural mechanism by which cognitive ability is improved, paving the way for improved management of cognitive decline.

Researchers at Michigan State University exposed rats to controlled lighting situations and studied the effects on their brains. They discovered that the rats lost 30% of the capacity of their hippocampus when performing spatial tasks after exposure to dim light. Rats exposed to bright light, however, showed significant improvement on the spatial task.

Like humans, rats are diurnal, and the researchers are confident that the test results can be extrapolated to humans. As Joel Soler, the study’s lead author puts it: “dim lights are producing dimwits.”

Sources:

1. Genetic Engineering and Biotechnology News:
   Study Sheds Light on How Darkness Produces Dimwits.

2. Hippocampus:
   Light modulates hippocampal function and spatial learning in a diurnal rodent species.