You know that a good night's sleep is crucial for well-being, performance, mood, and even maintaining a healthy diet. But a deep slumber may have even stranger implications than you know. In fact, the deeper your sleep, the stranger your dreams may be, according to a new report in the journal Dreaming.

In a two-day study, researchers tracked the sleep of 16 people, waking them four times each night to ask them to record their dreams. In the morning, they rated the dreams' emotional intensity and connection to their actual life.

The findings: As it got later, the participants' dreams became stranger and more emotional, morphing from true-to-life visions, like something about a book you recently read, to bizarre reveries featuring unrealistic situations (though often in familiar places or with familiar people), like a wild animal tearing up your yard.

Other research has shown that sleep-especially during the deep REM stages, which are most common late at night-is when the brain forms and stores memories. The study authors believe this may help explain why dreams that occur during this time contain such unusual and passionate scenarios. Whether or not you remember your dreams, however, may come down to your brain chemistry. French researchers found that "dream recallers" show higher level of activity in the medial prefrontal cortex and temporo-parietal junction, two areas that help you process information, than those who rarely recollect their nighttime thoughts.

Do you remember your dreams or notice that you dream more on certain nights? Tell us in the comments or tweet us @Shape_Magazine.