Did you know that the quality of your sleep can influence your ability to learn? Different stages of sleep have different effects on our learning performance. Dr. Tamaki’s team used magnetic resonance spectroscopy to measure the flexibility of participants’ brains to learn during sleep in visual perceptual learning tasks. They found that performance declined when NREM sleep occurred without REM sleep. The excitation/inhibition ratio increased during NREM sleep, which was linked to better performance in remebering and performing tasks that we have pratciced before. On the other hand, the excitation/inhibition ratio decreased during REM sleep, which was linked to the process of solidifying what we have learned. Also, temporary sleep disturbances significantly impaired performance improvements and the excitation/inhibition ratio. These findings suggest that different stages of sleep have distinct roles in learning through various effects in the brain.