What Dreams Are Made Of

Dreaming is a fundamental, seemingly timeless part of the human experience. For many thousands of years, humans have contemplated, theorized about, and given meaning to dreams.

Ancient cultures paid great attention to dreams. Among diverse ancient cultures, dreams took on many forms of meaning and significance. Sometimes dreams were warnings and messages from gods or divine entities. In some cases, dreams might be evidence of evil spirits.

Dreams were considered a vehicle for predicting the future, a way to communicate with the dead, a means to travel beyond the physical limits of the body. Dreams were believed to be both powerful and important.

In the 19th and early 20th centuries, physicians exploring the complicated emotional landscape of the human experience gave tremendous attention and significance to dreams. Sigmund Freud believed dreams were the necessary expression of the unconscious mind, a vehicle for the mind to explore repressed emotions and desires.

Carl Jung theorized that dreams provided a means to resolve conflicts between an individual's conscious and unconscious mind, conflicts that reflected the tensions of both the individual's internal sense of self and a sense of self in society.

By the mid-20th century, scientists were engaged in study of the cognitive and neurological mechanisms of dreaming, one part of a broader scientific exploration of sleep.

Today, new technologies enable us to observe and explore dreaming states in whole new ways.

Yet dreaming remains in many ways a deep mystery.

Despite sustained scientific exploration and attention, we still don't know the answer to the most fundamental question: Why do we dream?

For all the study and attention that dreams have received, its rather remarkable how much we don't know about dreaming -- not only about its purpose, but also about the mechanics in the brain that make dreams happen.

In this three-part series, we'll explore the world of dreams, looking at the latest science has to say about why we might dream, and the mechanics of dreaming in the brain.

We'll examine the content of dreams, and how dreams may both reflect and influence waking life. We'll look at disorders related to dreaming, and how health conditions and some medication can disrupt dreams.  Read more: