The Activation Synthesis theory of dreaming

• Reductionist theory
• Hobson and McCarley (1977) suggested a neurobiological theory of dreaming called the activation synthesis theory. They took the view that dreams occur when the brain tries to make sense (synthesis) of brain activity happening during sleep (activation). Therefore this theory states that dreams have NO MEANING.           
• Neurological activity changes significantly just before and during REM sleep
• Powerful electrical signals passing through the brain

  1. Arise from the pons in the brainstem

  2. From neurons that move the eyes

  3. Activate the limbic system (emotion)

  4. Travel up to the occipital lobe in the higher part of the brain

  5. Stimulate the whole cerebral cortex
• Higher brain areas try to attach some meaning to the electrical signals
• Dreaming


  The effort for us to give signals meaning
• To produce this synthesis the brain draws upon its own stored memories
• Because the spikes activate many areas of the brain the dream content maybe bizarre
• Random electrical signals


  • Signals produced when running
• Random electrical signals

  Can be synthesised in the mind and dreamed of as running
• Having an argument with a friend that day


  The brain might pick up on that memory and produce a dream of running away from that friend
• As the pons continues to fire randomly, we have to continuously try to synthesise them
• This is why the content of the dream can shift so suddenly