Activation synthesis theory

Activation Synthesis Theory is a neurobiological theory of dreams, put forward by Allan Hobson and Robert McCarley in 1977, which states that dreams are a random event caused by firing of neurons in the brain. This random firing sends signals to the body's motor systems, but because of a paralysis that occurs during REM sleep, the brain is faced with a paradox. It synthesizes a narrative by drawing on memory systems in an attempt to make sense of what it has experienced.

The original 1977 theory denied that dreams have meaning or are related to our real world environments. But this point drew criticism from other dream experts. In response, in 1988, Hobson published a revised theory acknowledging that dreams do reflect past memories, fears, hopes, and desires.