One of the biggest influences on dreams is how much or how little you’re sleeping. Being sleep-deprived for a night or two (or more) can make parts of your brain much more active when you finally do slip into REM sleep. You’re likely to have more vivid dreams if you’ve had some restless nights. You’re also more likely to recall those dreams, too.

Being pregnant is also a catalyst for vivid dreaming. Increased hormone production affects the way your brain processes thoughts and emotions. This often leads to some intense dreams.

Mental health disorders such as depression and anxiety, as well as bipolar disorder and other mood-related conditions, can trigger intense and sometimes disturbing or negative dreams and nightmares. The medications for these conditions, including antidepressants and antipsychotics, are also associated with a higher risk of nightmares.