No doubt, you've had dreams that were culled directly from your real life. In fact, you've likely had one in the past week. Some of them may have even replayed events that happened that same day. Relationship and job stress can play out in your dreams on a nightly basis when you're in the midst of turmoil. Sometimes dreams mirror events as they happened in your waking life; sometimes there's a slight twist. Other times, they're filled with imagery and symbolism. There are no constants when it comes to dreams because they're highly personal and vary from person to person, which is why they're difficult to study or quantify with any certainty. It's also tough because we know so little about how the brain operates -- whether it's dreaming or figuring out a math problem.
Here's what we do know: Dreams definitely play out events from our waking lives. To understand how this happens, we should take a look at the way the brain processes memories. We all know that we have both long- and short-term memory, but there are subdivisions under those umbrellas that show us a little more about how our brain works. Under the long-term heading, we have episodic and declarative memory. Declarative deals with things you can state (or declare) that you know. Think "the sky is blue," "two plus two is four," and "my favorite food is steak." Episodic memories are there because of an experience you had -- "I'm afraid of seagulls because of the time I went to beach when I was 12, and one of them bit my finger."
Both of these types of memories are stored in the hippocampus region of the brain, and if you've damaged that area somehow, you won't be able to form new declarative or episodic memories. This is why permanent amnesiacs often can't remember things like the name of their dog or their home address. Because dreams are often culled from real life, some researchers believe that the brain is pulling from the recently learned declarative memories. But that's where amnesiacs come in to seemingly disprove that theory. If you aren't able to remember what you ate for lunch that day when you're awake, then you probably shouldn't be able to recall it in a dream either, right? Not necessarily, according to studies performed with amnesiacs. Learn more on the next page.