Synesthesia, and Psychedelics, and Civilization! Oh My!

The Coast to Coast AM radio host George Noory just interviewed David Eagleman.  I only heard part of the interview, but what little I gleaned seemed quite interesting.

Dr. Eagleman spoke of synesthesia.  He said that around four percent of the population has synesthesia which is a fairly high number (more common than scientists used to think).  He pointed out that it isn’t considered a neurological disorder because there is no negative consequences for those who have it and in fact there are benefits.  Those with this condition (who are called synesthetes) actually have improved memories because abstract information is grounded in sensory experience (this relates to localized memory which is an ancient mnemonic device).  There are many ways senses and concepts can link together and almost everyone experiences this in mild forms.

I wondered if it might’ve been more common in the past.  Maybe our modern rational ego has helped to compartmentalize the mind and thus created more clear demarcations separating perception and thought.  This possibly could relate to Julian Jaynes theory about the bicameral mind.  Jaynes theorized that a natural function of the human brain was hearing other voices, and that a shift in early civilization changed something fundamental in how our brain operates (or rather how we operate our brain).  The theory is that primitives used to hear voices outside of them and the world was experienced animistically.  As such, there was no clearly defined separate sense of self, no inidividual ego with a sense of being in absolute control.  Everyone still hears other voices in their head such as the words of advice from your parents, but we’ve learned to compartmentalize our sense of self and disidentify with these other voices.  Schizophrenics don’t have this ability.

This relates to psychedelics as well.  Psychedelics loosen the constraints that civilization has placed on our brains.  Any normal person under the influence of psychedelics will experience such things as synesthesia, animistic perception, external voices, etc.  Psychedelics are able to to do this because they are processed in our brains like any other neurochemical.  In fact, the most common psychedelic in nature  is DMT and the human brain produces it in small quantities.  Terrence McKenna theorized that psychedelics helped to develop human consciousness.  McKenna’s theory might find support in other theories that synesthesia is common to all humans early in their individual development (which might be a carryover from when humans permanently lived in such a state of mind).  Other theories claim that language itself originated in synesthesia as language began with concrete experiences and vocalizations that then became abstracted.

Further related to all of this are Ernest Hartmann’s boundary types.  People tend towards either thin or thick boundaries which correlate to personality factors, but certain substances can influence our boundaries.  Psychedelics create thinner boundaries and amphetamines create thicker boundaries.  Besides perceptual alterations, thin boundaries also are necessary for the simple ability to sympathize with others.  Interestingly, creative types tend to have thinner boundaries and have an extremely higher rate of synesthesia.

If you want to check out some of my previous analysis of the topic of human experience of the world, then here is a blog post of mine from


And here is some interesting info I found around the web:

A developmental theory of synaesthesia, with long historical roots
by A.O. Halcombe, E.L. Altschuler, & H.J. Over (full paper)

The recent surge of scientific investigation into synaesthesia, ably reviewed by Hochel and Milan (2008), is representative of an increasing recognition that our various sensory modalities are intimately interconnected rather than separate. The origin of these interconnections is the subject of an intriguing theory by Maurer and Maurer (1988). They suggest that all of us begin life as synaesthetes, with subsequent neural development reducing the connections among the senses. We present some historical roots of the idea that human life begins with the senses intertwined. The influential 18th-century philosopher Jean-Jacques Rousseau described an early theory of child development in his book Emile (1762), hypothesizing that if “a child had at its birth the stature and strength of a man . . . all his sensations would be united in one place, they would exist only in the common ‘sensorium’.” A half-century later, a young Mary Shelley (1818) brought this idea into popular culture with the Frankenstein creature’s recollection of his early experience: “A strange multiplicity of sensations seized me, and I saw, felt, heard, and smelt, at the same time; and it was, indeed, a long time before I learned to distinguish between the operations of my various senses.” William James in The Principles of Psychology (1890) expressed a similar idea. In this context, the assumption of many 20th-century scientists that the senses were largely separate appears to be an historical aberration.

Terence McKenna’s “Stoned Ape” Theory of Human Evolution (or here)

Perhaps the most intriguing of Terence McKenna’s fascinating theories and observations is his explanation for the origin of the human mind and human culture.

To summarize: McKenna theorizes that as the North African jungles receded toward the end of the most recent ice age, giving way to grasslands, a branch of our tree-dwelling primate ancestors left the branches and took up a life out in the open — following around herds of ungulates, nibbling what they could along the way.

Among the new items in their diet were psilocybin-containing mushrooms growing in the dung of these ungulate herds. The changes caused by the introduction of this drug to the primate diet were many — McKenna theorizes, for instance, that synesthesia (the blurring of boundaries between the senses) caused by psilocybin led to the development of spoken language: the ability to form pictures in another person’s mind through the use of vocal sounds.

About 12,000 years ago, further climate changes removed the mushroom from the human diet, resulting in a new set of profound changes in our species as we reverted to pre-mushroomed and frankly brutal primate social structures that had been modified and/or repressed by frequent consumption of psilocybin.

Graveyard of the Gods

Metaphor is based in the relationship between metaphier and metaphrand, strengthened by paraphier and paraphrand. A metaphor’s effectiveness in conveying meaning is not inherent to the structure of language or the words themselves, but the range of associations and connections between all elements (some of which are mostly unconscious) – the most receptive and accustomed to these elements will be most affected by metaphor. Cross modal abstraction increases the power of metaphor by bolstering the connective elements of the words we choose (the metaphiers and paraphiers) when attempting to express something – this probably why such as high percentage of artists display synesthesia (1 in 7 artists as opposed to 1 in 200 normal population).

Globalization, Romanticism, and Owen Barfield
by Jim Davis

Abram (1996), McLuhan (1964), et al argue that the phonetic alphabet led to a kind of synesthesia, wherethe visual was transformed into written symbols experienced as sounds. Early cultures were auditory cultures, wherelanguage was only spoken. The phonetic alphabet enabled an efficient writing system. It also resulted in thediminution of memory as the sole repository of tradition, and the fixing of standardized and “official” versions inauthoritative text. Following this line of thinking, the spread of the corresponding consciousness tracks the spread ofliteracy and the technology of writing reproduction.