Activation Synthesis Theory of dreaming

Type of theory

Neurobiological theory of dreaming

About

Focuses on random activation of neurons and the brains effort to make sense of this through synthesis

Brainstem

Central trunk of brain that continues down to the spinal cord

Synthesise

To make sense and give meaning to dreams

Why a variety of neural activity takes place during sleep

Sleep helps brain to perform activities such as cleaning up brain and consolidating memories

Pons

Electrical signals passing through the brain during REM sleep. Inside the pons, there are neurons during REM sleep that send messages to activate limbic system

Limbic system

Involves hippocampus and amygdala involved in processing emotions and motivation and memories. Signals are then passed to the occipital lobe

Occipital lobe

Signals are received from limbic system and when activated, it causes the visual and imagery aspect of dreams

Cerebral cortex

Signals sent from pons and limbic system which stimulate regions responsible for learning, thinking, and organising info. Dreams are cerebral cortex’s attempt to find meaning in random signals it receives during REM sleep

Activation process

Activation of neurons

Parts of the brain involved with the activation process

• Occipital lobe activated

• Cerebral cortex stimulated

• Limbic system activated

Parts of the brain involved with the synthesis porcess

• Cerebral cortex

Process of activation synthesis

• High levels of neural activity in REM sleep (A)

• Signals arrive from pons which neurons are activated and they stimulate parts of brain:

  • Signals → Activates occipital lobe causing visual aspect of dreams (A)

  • Signals → Stimulates cerebral cortex responsible for learning, thinking and organising (A)

  • Signals → Activates limbic system responsible for emotions and motivation and memory (A)

• Synthesis process occurs where cerebral cortex attempts to make sense of activity using memories and experience hence dream experience (S)

Patients with damage to the brainstem don’t stop dreaming (Criticism)

• People who had brain damage can still dream even if usual signals aren’t sent

• Contradicts the theory

Evidence shows there’s some continuity to people’s dreams (Criticism)

• Some people have recurring dreams of a similar theme

• Suggests dreams aren’t completely random

Dreams can occur in NREM sleep (Criticism)

• Evidence shows of people dreaming in other stages of sleep even if they are not as vivid

• Therefore it isn’t a result of neural activity as it only occurs in REM sleep