The Origins of Human Art and Symbolism: Entoptic Phenomena and the Neurocognitive Model.

Designs that are found universally and thought to originate or be inspired by naturally-occuring visual effects within the eye. (Source:

Designs that are found universally and thought to originate or be inspired by naturally-occuring visual effects within the eye. (Source:

Entoptic visuals are a physiological effect that can be produced naturally in the visual processing center of any human. Not to be confused with optical illusions, they are visual sensations produced by mechanisms within the eye, namely in relation to the retina and under certain conditions.

Representation of “floaters”, caused by vitreous coagulations in the eye. (Source:

They often occur in linear zig-zag patterns, dots, and other abstract shapes, and can be caused by mechanisms including the movement of white blood cells in capillaries in front of the retina or floating coagulations of vitreous jelly within the eye. Other shapes produced by these documented phenomena include hourglass or bow-tie shapes, arcs, squiggly lines, and the “Purkinje Tree”, which is a visual imprint of the blood vessels within one’s own eye that can be seen when light shines into the pupil from an opportune angle. One can also produce a phosphene, or the perception of light and veiny or zig-zag-like lines by applying pressure to the closed eye.[2]

Most of these phenomena are caused by the viewing of a plain, solid background such as a clear sky. Needless to say, the phenomena could easily be encountered in daily life when outdoors. Another interesting phosphene-related visual phenomenon called “Prisoner’s Cinema” is known to occur when one is confined in darkness for extended periods of time. It presents as a “light show” in the darkness that can be amorphous but eventually takes familiar human or animal forms. It has commonly been noted by people practicing intense meditation or activities requiring long-term mental focus, such as pilots, astronauts, and truck drivers.[6] It is easy to imagine how the conditions of life in a cave might produce this effect, and the possible connection to cave art has been noted by researchers.[5] It is certainly reminiscent of some more abstract cave art forms, such as Chauvet Cave’s pointillism-style bison discussed in my post on hand motifs. More interestingly, all of the described entoptic phenomena thus far are also known to be produced by the brain during epileptic fits, migraines, and altered states of consciousness.[1]

Other researchers have studied art produced by schizophrenic patients and found striking similarities to entoptic figures. This has been linked to another type of entoptic imagery, called a ‘form-constant,’ thought to be produced in the visual cortex. These images are often geometric in style and linked to the nervous system. The “viewer” might associate them or mentally connect them with a familiar image or pattern, in which case they’re considered visual hallucinations. This type of entoptic imagery is often noted during altered states produced by use of entheogens or “natural” trance states induced by behaviors such as meditation and fasting.[8] It is also seen in schizophrenics.[7]

Entoptic imagery and schizophrenics: image from study by M. J. Horowitz, 1964.

Entoptic imagery and schizophrenics: image from study by M. J. Horowitz, 1964.

Research into entoptic visuals caused by mental imbalances and entheogens has shown that certain structural similarities found in entoptic imagery are experienced by many different individuals and through many different methods of induction. These similar visuals, or ‘form-constants’, were shown in 1964 in a study by M.J. Horowitz.[7]


Close-up of common entoptic-like cave designs. (Source:

The striking similarity of many of these entoptic images to humanity’s earliest-known symbolic imagery and geometric designs has caught the attention of a number of neurocognitive researchers. These researchers have incorporated them into a cognitive neurological framework that places entoptics and several other cognitive mechanisms at the critical juncture of humanity’s first verified demonstration of symbolic practice. That is, these designs “came first,” so to speak, physiologically and later were given symbolic meaning and totemic functions within a social system.[1] They might also be associated with the rise of early animistic belief or possibly shamanistic behaviors associated with hallucination and trance states, as seen in a number of documented cultures globally.[8]

Evidence for this physiological origin includes the prominence of classic entoptic designs such as nested curves, cross-hatching, dots, and zig-zag patterns in the earliest known forms of human symbolic expression separate from self-adornment– for example, the incised ochre blocks at Blombos Cave from the Middle Stone Age, dated to approximately 100,000 BC and discussed in more detail in my previous post. These are humanity’s earliest known symbolic objects. They’re also accompanied by similarly-decorated objects found at other cave sites in South Africa that seemed to appear around that geographic area in the same period.[2][3]

The developmental timeframes of the sociocognitive and physiological structures necessary to make these connections are unknown and will never truly be known. However, it is likely that, given the slow pace of evolutionary change in our brains and bodies, Homo sapiens‘ transition toward symbolic behavior (assuming the validity of the neurocognitive model) developed gradually over time rather than in an abrupt or “revolutionary” way. It seems possible that human cognitive complexity and symbolic behavior began even before the Middle Stone Age, but that material evidence for it either was subject to differential preservation outside of caves or hasn’t yet been found.

The following videos describe the history and science behind entoptic phenomena, as well as how to produce them yourself!


1. Morriss-Kay, Gillian M. 2010. The evolution of human artistic creativity. Journal of Anatomy, 216, 158-176.

2. Balter, M. 2009a. Early start for human art? Ochre may revise timeline.

3. Balter, M. 2009b. On the Origin of Art and Symbolism. Science, 323, 709-711.


5. Murchie, Guy. 1998. The Seven Mysteries of Life: An Exploration in Science and Philosophy. Houghton Mifflin Harcourt. p. 237. ISBN 0-395-95791-5.




Early symbolic behavior: Blombos Cave, South Africa

Blombos Cave, South Africa. (Source:

Blombos Cave is a South African coastal site located 300 KM east of Cape Town. It is currently the oldest known site containing solid evidence of symbolic thinking and behavior by Homo sapiens, with its earliest faunal and archaeological deposits dated to the Middle Stone Age period between 100,000-70,000 BC.[1][2][3]
Though the site has been in the process of excavation since 1991, it has been more recent findings at the site that have fundamentally changed our perspectives on the appearance and origins of abstract reasoning and capabilities.

Stratigraphy at Blombos Cave. (Source:

The importance of findings at this site cannot be underestimated. Archaeologists at Blombos Cave first rocked the discipline in 2002 after finding several pieces of geometrically-incised ochre dating to 77,000 BP, calling into doubt the prevailing idea that symbolic behavior and artistic innovation was part of a “revolution” that didn’t really occur until around 40,000 BP in Europe. Archaeologists found further evidence of symbolic thinking and possibly artistic tradition when they recovered 13 more engraved ochre pieces dated to 100,000 BP, removing any doubt about the previous discovery.[1] It is thought that this material was used in powder form as body paint, a fundamental and early human symbolic behavior extensively recorded in Europe as well. [5] Whether this body paint had practical or more social purposes is unknown.

Bone tools found at Blombos Cave, Middle Stone Age phase. (Source: Wikipedia)

Artifacts associated with an ochre processing “kit” dated to the Middle Stone Age. (Source: flickering

In order to tease out distinctions of practical use vs. symbolic use, discovering archaeologists Henshilwood and Mellars analyzed the pattern types and microscopically examined the incised designs, concluding that they had been made very intentionally in controlled circumstances. The incisions were consistent with the use of a specialized pointed stone tool and indicating some purpose other than powder grinding. Later excavations have found evidence of an “ochre workshop,” demonstrating the importance of these symbolic behaviors within the community.[3] Their meaning is not subject to speculation, but the geometric incised designs are consistent with those found at other Middle Stone Age sites, such as Wonderwerk cave and Klasies River cave. In addition to ochre artifacts, archaeologists also recovered bone tools, incised bone, a cluster of 24 perforated Nassarius Karussianus shell beads likely used for self-adornment, and retouched bifacial points. [6]

Incised ochre from Blombos Cave, dated to the Middle Stone Age. (Source:

Neurocognitive scientists associate these sorts of designs with the development of cognitive structures required for symbolic association and artistic tradition.[5] The findings at these caves have produced a paradigm shift in our understanding of the temporal and geographic origins of human artistic capabilities. It was long thought that this capability emerged in Europe at around 40,000 BC; however, this eurocentric notion has been upended.


1. Balter, M. 2009a. Early start for human art? Ochre may revise timeline.

2. Balter, M. 2009b. On the Origin of Art and Symbolism. Science, 323, 709-711

3. Henshilwood, Christopher S., et al. 2011. A 100,000-Year-Old Ochre-Processing Workshop at Blombos Cave, South Africa. Science, 334, 219-222.

4. Henshilwood, Christopher S. & d’Errico, Francesco. 2011. Homo symbolicus: the dawn of language, imagination and spirituality, Amsterdam ; Philadelphia, John Benjamins Pub. Co

5. Morriss-Kay, Gillian M. 2010. The evolution of human artistic creativity. Journal of Anatomy, 216, 158-176.


Our Artistic Relatives: Did Neanderthals Have the Cognitive Capacity to Produce Parietal Art? The Case of El Castillo Cave…

El Castillo Cave, in Cantabria Spain. (source:

El Castillo Cave, located in Cantabria, Spain, is known as the oldest cave art site in the world. It was discovered in 1903 and has since been found to contain parietal art and sequences spanning the Lower Paleolithic to the Bronze Age.

Hand stencils at El Castillo Cave. (source:

Lack of organic dating material, including lack of organic pigments, means that carbon-14 dating could not be used in determining its age. Instead it has undergone Uranium series dating via the calcite in minuscule stalactites that have formed over its parietal art. In this case, the oldest dates were found over hand motif stencils and disk-sized red ochre dots– two forms of symbolic expression that appear ubiquitously in the history of human cave art, regardless of geographic location, and which I have discussed in posts here, here, and here. The U-series dating, completed by Pike et al., gives the art a minimum age of almost 41,000 years. [1][2]

This short documentary includes more background information and video footage of El Castillo Cave, among 22 other Spanish Paleolithic cave art sites within or near Cantabria.

Lead archaeologist Alistair Pike believes that more recently-taken samples, which have not yet been analyzed, will prove to be even older– and in that case, it would prove very unlikely the human creation of these paintings. This leaves the other option: that Neanderthals were the artists and had comparative cognitive capabilities and/or grasp of symbolic thinking and behavior. Pike’s suspicion is that this is the case. In another recent study, charcoal found next to six paintings of seals in Nerja caves, Malaga, Spain, has been dated to between 42,300 and 43,500 years old. The paintings themselves will be dated in the next year or so, and if the dates match, they will take the title of oldest known paintings. Like Alistair Pike, José Luis Sanchidrián at the University of Cordoba, Spain believes the paintings are more likely to have been painted by Neanderthals than early modern humans.[5]

Chatelperronian body ornaments made and used by Neanderthals, found in Grotte du Renne Cave, France.

Chatelperronian body ornaments made and used by Neanderthals, found in Grotte du Renne Cave, France.

Likewise, sophisticated Chatelperronian artifacts recovered at the Cave of Grotte du Renne, France in the last 10 years have been found with well-identified Neanderthal remains. Opponents have asserted admixture of contexts and claimed that humans were responsible for the symbolic objects and sophisticated tools– however, recent Carbon-14 dating of the layers by Hublin et al. in 2012 has put this contention to rest and shown the stratigraphy to be intact.[3] These recent findings leave little room to debate the cognitive ability and capability of abstract, symbolic thought that Neanderthals must have possessed in order to produce these items in the first place.

The last holdout of archaeologists against Neanderthal symbolism protest that these “sophisticated” Neanderthal groups must have lifted their ideas from the work of incoming humans. However, even if this were the case, this doesn’t support a lack of Neanderthal capability to produce art and engage in symbolic practice. Clearly, if they were able to replicate sophisticated human “products,” they must have had substantial cognitive capacity and skill in their own right. Otherwise, it wouldn’t have been possible. Were Neanderthals less creative? Perhaps. Were they the apish, stooping, small-brained brutes depicted in history’s early misrepresentations? Clearly not–archaeological evidence throughout the last century has gradually dispelled the myth. The stark differences between dated and modern forensic reconstructions of Neanderthal skulls and bodies are very telling of how attitudes have shifted. However, a curious degree of anti-Neanderthal stubbornness in the literature and still-active vitriol between each theoretical side makes apparent the fact that some bias likely remains.

Neanderthal proponents such as archaeologist João Zilhão cite behaviors proven beyond a doubt to have been performed before human arrival, including burial of the dead, possession and use of ochre and manganese pigments, and sophisticated tool technologies–for example, a specialized birch sap spear construction technique so difficult that even modern experimental archaeologists have trouble replicating it.[4]

The perforated shells from level II of Zilhão's Neanderthal site, Cueva de los Aviones (after cleaning): (1) Acanthocardia tuberculata; (2–3). Glycymeris insubrica (maximum internal diameter of the perforations: 4.2, 9.5, and 6.8 mm, respectively).

The perforated shells from level II of Cueva de los Aviones (after cleaning): (1) Acanthocardia tuberculata; (2–3). Glycymeris insubrica (maximum internal diameter of the perforations: 4.2, 9.5, and 6.8 mm, respectively).

Different views of an ancillary metatarsal of horse with an excavation break from Cueva de los Aviones (Left) and binocular microscope close-ups of its pigment-dotted tip (Center and Right).

Different views of an ancillary metatarsal of horse with an excavation break from Cueva de los Aviones (Left) and binocular microscope close-ups of its pigment-dotted tip (Center and Right).

Pierced, pigment-stained shells from  João Zilhão's 2010 excavation of 2 Neanderthal sites.

Pierced, pigment-stained shells from João Zilhão’s 2010 excavation of 2 Neanderthal sites.

The photos shown above are of artifacts found at two Neanderthal sites excavated by Zilhão in the last five years. They are located in south-east Spain: the Cueva de los Aviones and the Cueva Antón, both in Murcia and dated to 50,000+ years BP.

Zilhao also makes a fair point: “’You don’t need to have shell beads, you don’t need to have artifacts with graphical representation to have behaviour that can be defined archaeologically as symbolic,’ he says. ‘Burying your dead is symbolic behaviour. Making sophisticated chemical compounds in order to haft your stone tools implies a capacity to think in abstract ways, a capacity to plan ahead, that’s fundamentally similar to ours.'”[4]

And so, the battle continues between staunch supporters and deniers of neanderthal cognitive capability. However, if the most recent U-series dates confirm even older ages for El Castillo’s art, this might just be the smoking gun that pro-Neanderthal archaeologists have been waiting for.

Modern interpretation of a Neanderthal man.

Modern interpretation of a Neanderthal man.


1. Pike, A. W. G.; Hoffmann, D. L.; Garcia-Diez, M.; Pettitt, P. B.; Alcolea, J.; De Balbin, R.; Gonzalez-Sainz, C.; de las Heras, C.; Lasheras, J. A.; Montes, R.; Zilhao, J. 14 June 2012. U-Series Dating of Paleolithic Art in 11 Caves in Spain. Science 336 (6087), 1409–1413. doi:10.1126/science.1219957

2. Amos, Jonathan. 2012. Red dot becomes “oldest cave art.” BBC News

3. Hublin, J. et al. 2012. New Radiocarbon Dates from the Grotte du Renne and Saint Césaire support a Neanderthal Origin for the Châtelperronian. PNAS, October 29, 2012.


5. MacErlean, Fergal. 2012. First Neanderthal cave paintings discovered in Spain. New Scientist. Retrieved 10 February 2012.

Paleolithic European cave artists: exploring identities and challenging myths

Hand painting and the appearance of the “hand” motif on rock is a phenomenon seen all over the globe, dating as far back as 32,000 BP (Aurignacian period) at several European sites, 12,000 BP in Borneo, and 9,000 BP in North America.[4]

Hand motifs in North America. (source:

Hand motifs in North America. (source:

Red ochre hand motifs are abundant in the famous cave site of Chauvet Cave, France. They are found throughout the entirety of the cave system. The works found in this particular cave were painted during the Aurignacian culture, dated to approximately 32,000 years ago. The entirety of the Brunel chamber, for example, is covered in more than 400 ochre-painted palm prints. The Red Panels Gallery’s “Panel of Hand Stencils” is comprised of several red ochre hand stencils as well as two drawings of animals–one horse and one mammoth. The hand stencils sit within the outlines of the animals.[3]

Panel of the Red Dots in Chauvet Cave, France. (Source: dons

The Panel of the Red Dots, another “hand-painted” work, is unusually abstract and is perhaps one of the earliest examples of pointillism–that is, the composition of a non-abstract form through the purposeful placement of pigmented dots. In a departure from the more commonly seen wall art composed of mostly-unmodified handprints, this large image in the shape of a bison was created by the artist(s) pressing the circular palmar portion of the hand against the wall, eventually forming an impressionistic animal-shaped piece. The consistency of the dots suggests that the painting was created by one person and was preconceived.

Hand motifs in Europe. (source:

Hand motifs in Europe, Borneo, Australia, and South America. (source:

Who were the makers of this art, how was it created, and what did it mean?

Archaeologists (demographically skewed toward male participation, historically) have long assumed that the makers of Paleolithic cave art were male, especially with the abundant depictions of animals and hunting scenes. Archaeologists uncovering these scenes over the last century have for the most part released interpretations imbued with the modern western understandings of gender divisions of labor, and imposed modern social meanings upon the artistic clues left by prehistoric peoples. Women appeared not to have a significant role in the creation of art or creation of any sort, for that matter (except for perhaps clothing, cooked food, and offspring…sound familiar?) Most explanations for the art have centered on shamanistic activity or teenage boys.[4] There is, in fact, no empirical justification for the idea of male-dominated cave art– it is likely a perception colored by our own cultural biases and history, in which male artists have played the most prominent artistic and religious roles.

Woman and child cave artists. (Image by Arturo Asencio)

Woman and child cave artists. (Image by Arturo Asencio)

New research by Penn State archaeologist Dean Snow, published in the 78th issue of American Antiquity in 2013, is turning the tables on our assumptions about the genders and identities of Paleolithic cave artists. Snow initially had the idea for studying handprint “signatures” left in caves after learning about hormone-related studies showing sexually dimorphic differences in finger ratios–of ring fingers and index fingers, specifically.

Drawings of average male and female hand morphology. Finger length ratios are often more varied and/or pronounced than those pictured. (Source: Dean Snow)

Drawings of average male and female hand morphology. Finger length ratios are often more varied and/or pronounced than those pictured. (Source: Dean Snow)

Ring finger length has been found to be highly correlated to in-utero testosterone exposure, and therefore a majority of men have a long ring finger relative to other fingers, namely in comparison to index finger length. Women, however, tend to have ring and index fingers of about equal length. Studies has found these ratios to be statistically reliable indicators of sex. Applying these studies to handprints at 8 Paleolithic cave sites, Snow found that a majority of handprints were almost certainly made by women. He was also able to distinguish, via hand morphology, that the smaller handprints were in fact not produced by adolescent boys. [1][2]
This has incredibly interesting implications for our reconstruction of social and gender roles in Paleolithic European groups. It would be interesting to see more investigations of this nature expanded to hand motif art throughout the globe, and well as in an even greater survey of European hand motif art for more evidence and theoretical fine tuning.

A short explanatory video produced by Dean Snow and Penn State University.



1. Snow, Dean. Sexual Dimorphism in European Upper Paleolithic Cave Art. 2013. American Antiquity 78(4), 746–761.