Table of ContentsView AllTable of ContentsOrigins of the TheoryThe Sleeping BrainKey Things to RememberReaction to the TheoryAre Dreams Meaningless?The AIM Model of Dreaming
Table of ContentsView All
View All
Table of Contents
Origins of the Theory
The Sleeping Brain
Key Things to Remember
Reaction to the Theory
Are Dreams Meaningless?
The AIM Model of Dreaming
Close
The activation-synthesis theory is a neurobiological explanation of why we dream. The question of why people dream has perplexed philosophers and scientists for thousands of years, but it is only fairly recently in history that researchers have been able to take a closer look at exactly what happens in the body and brain during dreaming.
Harvard psychiatrists J. Allan Hobson and Robert McCarley first proposed their theory in 1977, suggesting that dreaming results from the brain’s attempt to make sense of neural activity that takes place during sleep.
So what sort of things are happening in the sleeping brain? A wide variety of neural activity takes place as we slumber.
Sleep helps the brain perform a number of activities includingcleaning up the brainand consolidating memories from the previous day. Activation-synthesis theory suggests that the physiological processes that take place as we sleep are the cause of dreams.
Brain Activity Plays a Role in Dreaming
How does brain activity during sleep lead to dreaming?
Common Characteristics of Dreams
Hobson also suggested that there are five key characteristics of dreams. Dreams tend to contain illogical content, intense emotions, acceptance of strange content, strange sensory experiences, and difficulty remembering dream content.
What Is the Activation-Synthesis Model of Dreaming?
To summarize, the activation-synthesis theory essentially made three key assumptions:
So why does the brain try to make meaning from these random signals that take place during sleep?
“The brain is so inexorably bent upon the quest for meaning that it attributes and even creates meaning when there is little or none in the data it is asked to process,” Hobson suggested.
The initial publication of their research stirred up considerable controversy, particularly among Freudian analysts. Because many dream researchers and therapists invest considerable time and effort trying to understand the underlyingmeaning of dreams, the suggestion that dreams were simply the brain’s way of making sense of activity during sleep did not sit well with many.
While the activation-synthesis model of dreaming relies on physiological processes to explain dreaming, it does not imply that dreams are meaningless.
According to Hobson, “Dreaming may be our most creative conscious state, one in which the chaotic, spontaneous recombination of cognitive elements produces novel configurations of information: new ideas. While many or even most of these ideas may be nonsensical, if even a few of its fanciful products are truly useful, our dream time will not have been wasted.”
Thanks to modern advances in brain imaging and the ability to monitor brain activity, researchers now understand more about the sleep-wake cycle, the different stages of sleep, and the different states ofconsciousness.
The more recent version of the activation-synthesis theory is known as the AIM model, standing for activation, input-output gating, and modulation.
This newer model tries to capture what happens in the brain-mind space as consciousness changes through waking, non-REM, and REM sleep states.
A Word From Verywell
The reasons and meanings behind dreaming have fascinated philosophers and researchers for centuries. Activation-synthesis theory added an important dimension to our understanding of why we dream and stressed the importance of neural activity during sleep.
As new technology emerges for studying the brain and sleep processes, researchers will continue to make new advances in our understanding of why we dream, in knowledge regarding states of consciousness, and in comprehending the possible meaning behind our dreams.
7 Theories About Why People Dream
4 SourcesVerywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Hobson JA, McCarley RW.The brain as a dream-state generator: An activation-synthesis hypothesis of the dream process.Am J Psychiatry.1977;134(12):1335-1348. doi:10.1176/ajp.134.12.1335Oniz A, Inanc G, Taslica S, Guducu C, Ozgoren M.Sleep Is a Refreshing Process: An fNIRS Study.Front Hum Neurosci. 2019;13:160. doi:10.3389/fnhum.2019.00160American Psychological Association. APA Dictionary of Psychology.AIM Model.Washington, DC: American Psychological Association 2020 https://dictionary.apa.org/aim-modelHobson, JA.REM sleep and dreaming: Towards a theory of protoconsciousness.Nature Reviews Neuroscience. 2010;10(11): 803–813. doi:10.1038/nrn2716
4 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Hobson JA, McCarley RW.The brain as a dream-state generator: An activation-synthesis hypothesis of the dream process.Am J Psychiatry.1977;134(12):1335-1348. doi:10.1176/ajp.134.12.1335Oniz A, Inanc G, Taslica S, Guducu C, Ozgoren M.Sleep Is a Refreshing Process: An fNIRS Study.Front Hum Neurosci. 2019;13:160. doi:10.3389/fnhum.2019.00160American Psychological Association. APA Dictionary of Psychology.AIM Model.Washington, DC: American Psychological Association 2020 https://dictionary.apa.org/aim-modelHobson, JA.REM sleep and dreaming: Towards a theory of protoconsciousness.Nature Reviews Neuroscience. 2010;10(11): 803–813. doi:10.1038/nrn2716
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Hobson JA, McCarley RW.The brain as a dream-state generator: An activation-synthesis hypothesis of the dream process.Am J Psychiatry.1977;134(12):1335-1348. doi:10.1176/ajp.134.12.1335Oniz A, Inanc G, Taslica S, Guducu C, Ozgoren M.Sleep Is a Refreshing Process: An fNIRS Study.Front Hum Neurosci. 2019;13:160. doi:10.3389/fnhum.2019.00160American Psychological Association. APA Dictionary of Psychology.AIM Model.Washington, DC: American Psychological Association 2020 https://dictionary.apa.org/aim-modelHobson, JA.REM sleep and dreaming: Towards a theory of protoconsciousness.Nature Reviews Neuroscience. 2010;10(11): 803–813. doi:10.1038/nrn2716
Hobson JA, McCarley RW.The brain as a dream-state generator: An activation-synthesis hypothesis of the dream process.Am J Psychiatry.1977;134(12):1335-1348. doi:10.1176/ajp.134.12.1335
Oniz A, Inanc G, Taslica S, Guducu C, Ozgoren M.Sleep Is a Refreshing Process: An fNIRS Study.Front Hum Neurosci. 2019;13:160. doi:10.3389/fnhum.2019.00160
American Psychological Association. APA Dictionary of Psychology.AIM Model.Washington, DC: American Psychological Association 2020 https://dictionary.apa.org/aim-model
Hobson, JA.REM sleep and dreaming: Towards a theory of protoconsciousness.Nature Reviews Neuroscience. 2010;10(11): 803–813. doi:10.1038/nrn2716
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