The activation synthesis theory of dreaming Flashcards
Who created the theory and what is the theory??
Hobson and McCarley came up with a neuropsychological theory of dreaming, called the activation synthesis theory.
They took the view that dreams occur when the mind tries to make sense (synthesis) of the brain activity happening during sleep ( activation ) . Contrast to Freud, they believe dreams have no actual meaning.
What does research show ?
Where do these signals come from ?
neuronal activity changes significantly just before and during REM sleep. At this point of the sleep cycle, powerful electrical signals pass through the brain like a wave. In readings from brain scans, they appear as sudden spikes.
The signals arise from the pons in the brainstem and from the neurons that moves the eyes, then to activate the limbic system as well as travelling up to the occipital lobe in the higher part of the brain
What does Hobson and McCarley’s theory say that these spikes were?
sending a random surge of stimulation through the brain at frequent intervals. This activates the whole cerebral cortex, and as a result the higher brain tries to attach some meaning to what it happening .
What leads us to dreaming ?
The effort to give signals meaning is what leads us to dreaming.
In order to produce synthesis, the brain draws upon its own stored memories. However, these spikes activate many parts of the brain at the same time, the outcome is often strange.
Examples
The randomly produces spikes may be like those produced when running, a sleeping person could then synthesis those signals in there mind and dream of running.
If they had an argument with neighbour that day, brain may pick up of that memory and produce a dream of running after or away from the neighbour.
Why do content of dreams shift so suddenly?
As the pons continues to fire random signals at the higher parts of the brain, they have to constantly make sense of the brain, this is why content of dreams shift so suddenly.
state 2 criticisms of the theory
Theory considered too reductionists - dreams highly complex, although bizarre but full of meaning.
Critics say its wrong to reduce this down to simple neuronal processes
Compared to more holistic Freudian theory, its too simplistic.
The theory is challenged by the evidence that dreams are not as random as the neuronal activity in the brain, research suggests dreams can be highly coherent and often direct relationship to experiences from the day.
State 3 criticisms of the theory
Theory is challenged by evidence that there is some continuity to peoples dreams. Some people have recurring dreams and dreams with similar themes. People wake up and go back to sleep again and sometimes pick up on the same dream. Patterns like this go against the idea of randomness
Dreams occur in non REM stages, although brain activity is reduced in other stages of dreaming, there is evidence of dreaming even if not as vivid. The fact that we have better recall for dreams in REM sleep may be because we are more likely to wakeup up than NON REM.
Patients with damage to brainstem don’t stop dreaming which contradicts the theory, even though usual signals are not being sent to the brain of these patients, they still have dreams. This is better explained by theories which suggest that dreams organise events from the day into memories especially if parts of the brain used for this, are still functioning.
