Dream Evolution and Graphical Imagery

Dream Evolution Introduction

Dream Evolution and Graphical Imagery attempts to explain why dream content is mainly graphical. This is accounted for by the evolution of dreaming.

Dream Evolution – Why Are Dreams Mainly Graphical?

I was always perplexed by the mystery that if our dreams are so meaningful why are they presented in such a convoluted manner? Why don’t dreams just state what they mean in plain simple English or whatever native language the dreamer speaks? The same brain that formulates complex plots, clever metaphors and amazing graphics does not seem to be able to translate the content into our native language, not even subtitles.

Instead, we receive these images which appear to have nothing to do with our lives: Tyrannosaurus Rex, Russian Commandos, aliens destroying earth; all in plots that do not seem to make any sense at first glance.

dream evolution Dream Evolution | Taking Control of Life

I was totally shocked the first time a psychoanalyst interpreted one of my dreams. He accurately portrayed what was going on in my life at that time from a dream that seemed interesting, but what I thought had nothing to do with my life. Much of what he said I wanted to deny, but I knew that it was true. My dream betrayed some of my dreaded truths which I was ashamed to admit.

Dream Evolution

I am not a scientist so forgive my ignorance of certain facts. I had originally guessed that dreaming might have evolved over 500,000 years ago with humans, I did not realize that so many other creatures also dreamed. Since that time, I have read research articles from MIT and the University of Chicago that not only prove that birds and mice dream, but the scientists can figure out what these creatures are dreaming about.

Researchers place electrodes in the brains of the birds and record the firing of their neurons both during the day and at night while they are dreaming. In one of the studies, the same pattern of neurons which fired while the birds were singing their “birdsong” were, also, firing at night while the birds were dreaming. The birds are practicing or learning their songs, presumably to attract mates.

Rats that have been trained to go through mazes dream about going through the maze at night. Researches can predict exactly where the rat is in the maze during the dream based on the identical neuron patterns firing when the rat was physically in the maze.

The implication here is that anatomical structures and chemical processes for dreaming had to be developed prior to the divergence between the species that would become man and those that would become birds. This divergence took place approximately 250 million years ago during the Jurassic period.

Since most mammals dream and birds dream, that would mean that the dreaming function also existed 250 million years ago. Chances are that dream evolution started 100 million years or so prior to the split. Since dreaming seems to be heavily linked with learning and committing experiences into long term memory, it was probably an essential part of survival that creatures at this time learn from their experiences as quickly as possible.

Scientists estimate that the first signs of a brain developing was 500 million years ago in worms.

Dream Evolution

An example of an early dreamer. The Cynognathus was a member of the Synapsid line that eventually evolved into mammals. It is one of the mammal-like reptiles that existed toward the end of their reptile existence before the divergence to mammals was completed. From Wikipedia Creative Commons

“These extinct synapsids are often referred to as “mammal-like reptiles” because some have a superficially reptilian appearance. However, all are descendants of a common ancestor that existed after the divergence between Synapsida and Reptilia, which means they are all more closely related to extant mammals than to any reptile. A more accurate name for these extinct species is “non-mammalian synapsids,” which reflects the fact that they are members of the synapsid lineage, but are not mammals.” (X)

“Non-mammalian synapsids are an extremely important part of the fossil record because they document the evolutionary history of many of the distinctive features of mammals, such as the presence of a bony secondary palate, the incorporation of bones from the lower jaw into the middle ear, teeth with complex occlusion patterns, and upright limbs. Morphological features, such as the presence of a single opening behind the eye socket around which jaw musculature attaches, help us recognize members of the synapsid lineage in the fossil record.“ (

The Fossil Non-mammalian Synapsid Collection at The Field Museum


My guess is that a few hundred million years ago, the creatures that were capable of dreaming were on the basic level of what rats and birds are today, practicing basic survival skills.

Evolutionary Chart showing that the Amniota was the last common link between Reptiles and Mammals. Birds diverged from reptiles somewhat later, but must have carried the function of dreaming through reptile like species until they diverged. Amniota were egg laying species. The Cynognathus pictured would fall in the Cynodontia grouping.


Simplified phylogeny showing relationships among tetrapods. Groups with living members are shown in bold; extinct groups are in plain type. Modified from Angielczyk (2009). From “The Field Museum”






Dreams appear to be triggered by emotions. Fear, desire or seeking, anger, love, yearning – normally something that happens in the dreamer’s current life triggers a certain emotion and this becomes the trigger for a certain dream theme or topic.

“Emotions are an internally directed sensory modality that provides information about the current state of the bodily self, as opposed to the state of the object (outside) world.” (X)

For the most part dreams typically express the dreamer’s emotional state in graphical form. Although they are often accompanied by some language, the metaphorical graphics tend to carry the main message and most of the content. The brain selects or creates metaphorical graphics which it matches to the emotional state that the dreamer is experiencing. There is no error, the unconscious self knows exactly what it is sensing.

We may be able to remain in denial during the day, but the reality of our lives is dealt with during the dream process. However, this is where repression might come in – if reality conflicts to strongly with the ego or self-image denial will take over when awake.

Emotional Apparatus of the Brain

“The hippocampus belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory,

Psychologists and neuroscientists generally agree that the hippocampus plays an important role in the formation of new memories about experienced events (episodic or autobiographical memory).[40][48] Part of this function is hippocampal involvement in the detection of new events, places and stimuli.[49] The hippocampus also encodes emotional context from the amygdala. This is partly why returning to a location where an emotional event occurred may evoke that emotion. There is a deep emotional connection between episodic memories and places.[50]

Experiments using intrahippocampal transplantation of hippocampal cells in primates with neurotoxic lesions of the hippocampus have shown that the hippocampus is required for the formation and recall, but not the storage, of memories.” [53] (X)

Image from “Medical News Today”



Since the hippocampus processes experiences into long-term memory or episodic memory – during dreaming it, also, appears to access older memories that fit a similar pattern on an emotional level and incorporates them into the dream plot – hence we end up at the house we grew up in or the grade school we attended in some dreams. The hippocampus appears to store the essence or tag of an episodic event, but, complete memories are often stored in multiple places through out the cortex = association cortices within the proximity of where the sensory functions lie. The auditory portion of the event would be in the temporal lobe in proximity to the hearing apparatus, etc.


Hippocampus from Wikipedia Commons

Temporal Lobe – Left Hemisphere from Wikipedia Commons


The Ventromedial Prefrontal Cortex

The following excerpt is from Wikipedia and is included to give the reader an idea of the interconnectivity of the brain. These areas are active during dreaming which is a highly intensive process requiring high speed transmission through the neurons. The axons between the ventromedial prefrontal cortex and the limbic area is covered with myelin (see below).


“The ventromedial prefrontal cortex (vmPFC) is a part of the prefrontal cortex in the mammalian brain. The ventral medial prefrontal is located in the frontal lobe at the bottom of the cerebral hemispheres and is implicated in the processing of risk and fear.

The ventromedial prefrontal cortex is connected to and receives input from the ventral tegmental area, amygdala, the temporal lobe, the olfactory system, and the dorsomedial thalamus. It, in turn, sends signals to many different brain regions including; The temporal lobe, amygdala, the lateral hypothalamus, the hippocampal formation, the cingulate cortex, and certain other regions of the prefrontal cortex.[4] This huge network of connections affords the vmPFC the ability to receive and monitor large amounts of sensory data and to affect and influence a plethora of other brain regions, particularly the amygdala.

The amygdala plays a significant role in instigating the emotional reactions associated with anger and violence.

Ventromedial areas of the pre-frontal cortex have not yet been clearly established, although the associated with pure emotion regulation

The temporal lobe is involved in processing sensory input into derived meanings for the appropriate retention of visual memory, language comprehension, and emotion association

The temporal lobe communicates with the hippocampus and plays a key role in the formation of explicit long-term memory modulated by the amygdala (X)”

The function of dreaming ties heavily in with the function of learning long term memory conversion appears to take place in the hippocampus, the hippocampus may have been the main cortex prior to the evolution of what is now known as the neocortex. The hippocampus is very active during the dream state and therefore is thought to, also, be laying down long term memory patterns while we dream. It would make sense that the hippocampus served a similar function for creatures 250 to 300 million years ago. Memory would have to be formed for survival.

Dream Evolution – Myelin or White Matter

The basic brain design between birds, mice and humans is similar in that the same apparatus exists with the exception that humans developed large frontal lobes beginning around 2 million years ago along with other large primates. The main difference between large primate brains and that of humans is the presence of white matter or ‘myelin” which is a white substance that covers the axons of neurons in several areas.

Axons are the long extensions of neurons which carry nerve impulses to the next neuron. There are billions of neurons in the brain.

Dream Evolution

From Wikipedia Creative Commons

“This myelin sheath greatly speeds transmission: the implication of the larger amount of white matter in human frontal lobes is that the regions are more profusely interconnected in humans. There is also more white matter in the human right hemisphere than the left.” This could be accounted for by the high speed required to conduct all the transmissions to produce more complex dreams than those of mice, great apes, etc.

There is a high concentration of myelin covered axons which connect the limbic system (emotional apparatus) to the frontal lobes or more specifically, the ventromedial prefrontal cortex, two very active areas while dreaming.

Myelin-Sheath – Mosbys Medical Dictionary 9th edition


Evolution of Language

It is estimated that languages have only existed for the past 40,000 years. (X) Prior to this all thinking had to be on a graphical basis, without language the only way to imagine phenomena is based on what you have seen – possibly why the prehistoric cave drawings are of animals – they had no other way of expressing themselves. To communicate the concept of a mammoth or the concept of an animal running was inexpressible in any other way.

Since dreaming had been taking place a couple hundred million years prior to the development of language, the rapid handling of graphical images is hardwired into the brain. The neuronal pathways for connecting the various sensory images of sight, sound, touch, taste and smell not only work instantly but simultaneously. Images had to form fast for creatures to survive. 99.99% of all life form that once existed have gone extinct – ‘the quick and the dead’.

The graphical neuronal pathways are innate and operate unconsciously. They are standard equipment that we are born with and develop naturally as we grow, like breathing or heartbeat – no learning or thinking required. We must learn languages, languages are secondary not primary processes. We must think when we use language.

Language must be processed sequentially – one word at a time. Graphically, complete images are transmitted in fractions of a second imparting large quantities of information rapidly.

Conclusion of Dream Evolution

We dream with a high level of graphical metaphors since high speed neuronal pathways have evolved hundreds of millions of years to take emotionally charged feelings or thoughts and convert them into meaningful patterns from our stored memories to help us navigate through our individual realities or world. Language is in its infancy in comparison with graphical images for communicating within the brain – language could not keep up with the flow of information when the unconscious is accessed. The thoughts or dream content would be lost before they could be converted into a language format.





References for Dream Evolution [edit]

  1. Jump up^Bechara A, Damasio H, Tranel D, Anderson SW (January 1998). “Dissociation Of working memory from decision making within the human prefrontal cortex”. J. Neurosci. 18 (1): 428–37. PMID 9412519.
  2. Jump up^Ongur, D. (2000). “The Organization of Networks within the Orbital and Medial Prefrontal Cortex of Rats, Monkeys and Humans”. Cerebral Cortex. 10(3): 206–219. doi:1093/cercor/10.3.206. ISSN 1460-2199.
  3. Jump up^Finger, E. C.; Marsh, A. A.; Mitchell, D. G.; Reid, M. E.; Sims, C.; Budhani, S.; Kosson, D. S.; Chen, G.; Towbin, K. E.; Leibenluft, E.; Pine, D. S.; Blair, J. R. (2008). “Abnormal Ventromedial Prefrontal Cortex Function in Children with Psychopathic Traits During Reversal Learning”. Archives of General Psychiatry. 65 (5): 586–594. doi:1001/archpsyc.65.5.586. PMC 3104600. PMID 18458210.
  4. ^ Jump up to:ab c Carlson, Neil R. Physiology of Behavior. 11th ed. Boston: Pearson, 2013. Print.
  5. Jump up^Decety, J; Michalska, K (2010). “Neurodevelopmental changes in the circuits underlying empathy and sympathy from childhood to adulthood”. Developmental Science. 13 (1): 886–899. doi:1111/j.1467-7687.2009.00940.x. PMID 20977559.
  6. Jump up^Aaron D Boes; et al. (2011). “Behavioral effects of congenital ventromedial prefrontal cortex malformation”. BMC Neurology. 11 (151). doi:1186/1471-2377-11-151.
  7. ^ Jump up to:ab c d Bechara, A; Tranel, D; Damasio, H (2000). “Characterization of the decision-making deficit of patients with ventromedial prefrontal cortex lesions” (PDF). Brain. 123 (11): 2189–202. doi:1093/brain/123.11.2189. PMID 11050020.
  8. ^ Jump up to:ab c d Michael Koenigs; et al. “Damage to the prefrontal cortex increases utilitarian moral judgements” (PDF). Nature. 446: 908–911. doi:1038/nature05631.
  9. Jump up^Fellows, L. K.; Farah, M. J. (2007). “The Role of Ventromedial Prefrontal Cortex in Decision Making: Judgment under Uncertainty or Judgment Per Se?”. Cerebral Cortex. 17 (11): 2669–674. doi:1093/cercor/bhl176.
  10. Jump up^Zald, D. H.; Andreotti, C. (2010). “Neuropsychological assessment of the orbital and ventromedial prefrontal cortex”. Neuropsychologia. 48 (12): 3377–3391. doi:1016/j.neuropsychologia.2010.08.012.
  11. Jump up^Asp, E.; Manzel, K.; Koestner, B.; Cole, C. A.; Denburg, N. L.; Tranel, D. (2012). “A neuropsychological test of belief and doubt: damage to ventromedial prefrontal cortex increases credulity for misleading advertising”. Frontiers in Neuroscience. 6. doi:3389/fnins.2012.00100.
  12. Jump up^Taber-Thomas, B. C.; Asp, E. W.; Koenigs, M.; Sutterer, M.; Anderson, S. W.; Tranel, D. (2014). “Arrested development: early prefrontal lesions impair the maturation of moral judgement”. Brain. 137 (4): 1254–1261. doi:1093/brain/awt377. PMC 3959552. PMID 24519974.
  13. Jump up^Nicolle, A. & Goel, V. (2013). What is the role of ventromedial prefrontal cortex in emotional influences on reason? In I. Blanchette (Ed.), Emotion and Reasoning. Psychology Press.
  14. Jump up^Hu, C; Jiang, X (2014). “An emotion regulation role of ventromedial prefrontal cortex in moral judgment”. Front. Hum. Neurosci. 8: 873. doi:3389/fnhum.2014.00873.
  15. ^ Jump up to:ab c d Carlson, N. (2012). Physiology of Behavior (11th ed.). Harlow: Prentice Hall.
  16. Jump up^Nili, Uri; Goldberg, Hagar; Weizman, Abraham; Dudai, Yadin (2010). “Fear Thou Not: Activity of Frontal and Temporal Circuits in Moments of Real-Life Courage”. Neuron. 66 (6): 949–962. doi:1016/j.neuron.2010.06.009. ISSN 0896-6273. PMID 20620879.
  17. ^ Jump up to:ab Alexander Hänsel & Roland von Känel (2008). “The ventro-medial prefrontal cortex: a major link between the autonomic nervous system, regulation of emotion, and stress reactivity?” (PDF). BioPsychoSocial Medicine. 2 (21). doi:1186/1751-0759-2-21.
  18. Jump up^Motzkin, Julian C.; Newman, Joseph P.; Kiehl, Kent A.; Koenigs, Michael (2011). “Reduced prefrontal connectivity in psychopathy”. The Journal of Neuroscience. 31 (48): 17348–48. doi:1523/jneurosci.4215-11.2011.
  19. Jump up^Chester, David S.; Lynam, Donald R.; Milich, Richard; DeWall, C. Nathan (2017-12-01). “Physical aggressiveness and gray matter deficits in ventromedial prefrontal cortex”. Cortex. 97 (Supplement C): 17–22. doi:1016/j.cortex.2017.09.024.
  20. Jump up^Insel, TR (2009). “Disruptive Insights in Psychiatry: Transforming a Clinical Discipline”. Journal of Clinical Investigation. 119 (4): 700–705. doi:1172/jci38832. PMC 2662575. PMID 19339761.
  21. Jump up^Koenigs, M., & Grafman, J. (2009). Post-traumatic stress disorder: The role of medial prefrontal cortex and amygdala. The Neuroscientist : A Review Journal Bringing Neurobiology, Neurology and Psychiatry, 15(5), 540–548. http://doi.org/10.1177/1073858409333072.
  22. Jump up^Schechter DS, Moser DA, Giacobino A, Stenz L, Gex-Fabry M, Adouan W, Cordero MI, Suardi F, Manini A, Sancho-Rossignol A, Merminod G, Aue T, Ansermet F, Dayer AG, Rusconi-Serpa S. (epub May 29, 2015) Methylation of NR3C1 is related to maternal PTSD, parenting stress and maternal medial prefrontal cortical activity in response to child separation among mothers with histories of violence exposure. Frontiers in Psychology. http://journal.frontiersin.org/article/10.3389/fpsyg.2015.00690/abstract
  23. Jump up^Grossman, M.; Eslinger, P. J.; Troiani, V.; Anderson, C.; Avants, B.; Gee, J. C.; Antani, S. (2010). “THE ROLE OF VENTRAL MEDIAL PREFRONTAL CORTEX IN SOCIAL DECISIONS: CONVERGING EVIDENCE FROM fMRI AND FRONTOTEMPORAL LOBAR DEGENERATION”. Neuropsychologia. 48 (12): 3505–3512. doi:1016/j.neuropsychologia.2010.07.036. PMC 2949451. PMID 20691197.
  24. Jump up^Northoff, G (2010). “Region-based approach versus mechanism-based approach to the brain”. Neuropsychoanalysis: An Interdisciplinary Journal for Psychoanalysis and the Neurosciences. 12 (2): 167–170. doi:1080/15294145.2010.10773640.
  25. Jump up^Quirk, Gregory J.; Russo, Gregory K.; Barron, Jill L.; Lebron, Kelimer (2000). “The Role of Ventromedial Prefrontal Cortex in the Recovery of Extinguished Fear”. The Journal of Neuroscience. 20 (16): 6225–231.
  26. Jump up^Milad Mohammed, R.; Quinn, Brian T.; Pitman, Roger K.; Orr, Scott P.; Fischl, Bruce; Rauch, Scott L. (2005). “Thickness of ventromedial prefrontal cortex in humans is correlated with extinction memory”. Proc. Natl. Acad. Sci. U.S.A. 102 (30): 10706–30. doi:1073/pnas.0502441102. These results are a possible factor for explaining why different people show different degrees of controlling their fear.
  27. Jump up^Nieuwenhuis, I. L.; Takashima, A. (2011). “The role of the ventromedial prefrontal cortex in memory consolidation”. Behavioural Brain Research. 218(2): 325–334. doi:1016/j.bbr.2010.12.009.
  28. Jump up^Milne, Elizabeth; Grafman, Jordan (2001). “Ventromedial prefrontal cortex lesions in humans eliminate implicit gender stereotyping”. The Journal of Neuroscience. 21 (12): RC150.
  29. ^ Jump up to:ab Carlson, N. (1977). Physiology of Behavior (11th ed.). Boston: Allyn and Bacon. pp. 621–622. ISBN 0-205-05706-3.
  30. Jump up^Bolla, K.; Ernst, M.; Kiehl, K.; Mouratidis, M.; Eldreth, D.; Contoreggi, C.; London, E. (2004). “Prefrontal Cortical Dysfunction in Abstinent Cocaine Abusers”. The Journal of Neuropsychiatry and Clinical Neurosciences. 16 (4): 456–464. doi:1176/appi.neuropsych.16.4.456.
  31. Jump up^Kalivas, P.W.; Volkow, N.; Seamans, J. (2005). “Unmanageable Motivation in Addiction: A Pathology in Prefrontal-Accumbens Glutamate Transmission”. Neuron. 45 (5): 647–650. doi:1016/j.neuron.2005.02.005. PMID 15748840.
  32. Jump up^Van; den Oever, M. C.; Rotaru, D. C.; Heinsbroek, J. A.; Gouwenberg, Y.; Deisseroth, K.; Stuber, G. D.; Smit, A. B. (2013). “Ventromedial Prefrontal Cortex Pyramidal Cells Have a Temporal Dynamic Role in Recall and Extinction of Cocaine-Associated Memory”. The Journal of Neuroscience. 33 (46): 18225–18233. doi:1523/JNEUROSCI.2412-13.2013. PMC 3828471. PMID 24227731.

External links