Critical reaction two-page assignment for biological anthropology class. Directions/instructions are attached as a word docume

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Cognition and art: the current interdisciplinary approach Dahlia W. Zaidel∗

For decades discussions of cognition and art were anchored in psychological and perceptual theories alone and were focused primarily on pictorial art, but in recent years a major conceptual shift has altered the discussions. Now, insights, concepts, and findings from archaeology, anthropology, brain evolution, biology, genetics, neurology, and neuroscience together with psychology and perception are leading into deeper scholarly explorations of the topic than was done previously. The implication is that the relationship between cognition and art can be fully grasped only when scholarship from all these disciplines is included in the discussions. We now emphasize that the diverse art forms practiced ubiquitously in human societies have a communicative value with deep biological roots and that art is another expression of the symbolic cognition that is the hallmark of the human brain, but that early societal-type organization played a pivotal role in the enduring practice of art. Moreover, neurological evidence from artists with brain damage suggests that the communicative nature of art is neuronally damage-resistant, much more so than language. Rather than placing pictorial art center stage, as was done previously, the current interdisciplinary approach includes all the arts, points to sociocultural triggers for art practice, to the demographic conditions that prevailed in art’s early beginnings, and to the interplay of these evolutionarily adaptive factors with deep biological motivations in the artist. © 2013 John Wiley & Sons, Ltd.

How to cite this article: WIREs Cogn Sci 2013, 4:431–439. doi: 10.1002/wcs.1236

INTRODUCTION

Amajor characteristic of human cognition issymbolic and abstract thinking. The use of arbitrary symbols allows representation of a wide range of ideas and concepts in a multitude of styles and mediums, and to communicate them to others. Symbolic reference is the key cognition for language1 and also for art; both represent separate communicative systems in human culture, although, as is described in subsequent sections, the symbolic reference alone is not a sufficient condition for the emergence of art in human life. That is not to say that art need be symbolic and abstract in order to be considered art. However, in order to be a useful communicative system, the arbitrary nature of the reference has to be valued, accepted, and learned

∗Correspondence to: [email protected] Department of Psychology, University of California, Los Angeles (UCLA), Los Angeles, CA, USA

The authors have declared no conflicts of interest for this article.

by members of the community where the art is practiced.2,3

For decades, art and cognition have been mainly studied with emphasis on pictorial art, mostly in the viewer and generalized to the artist.4–9 The fact that art consists of multiple forms of expression, and that it is a referential system in all the visual arts (e.g., dance, theater, ornaments) plus music and writing (e.g., poems, novels) had largely been neglected. The traditional approach’s limited scope constrained further insights into the nature of art as well as into the artist’s brain and motivation, and the viewer’s interest. Deeper and wider questions have been posed in recent years to include scholarships and discussions emanating from diverse fields.10–13 The current approach is interdisciplinary and represents a conceptual shift in the way art is viewed; it assumes that a full understanding can ultimately be achieved by examining how human brain evolution and adaptation, biological needs, genetics, neurology, and neuroscience, together with visual

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perception, have shaped art in all its forms and expressions today.

It is significant to the full understanding of art that humans are the only ones to produce it spontaneously, and it is practiced to various extents in all countries today.14,15 Some societies include all members in the production while in others only a select group is involved, some continue to employ unaltered traditional methods while others experiment and innovate, some barely produce while others are enormously prolific. Recognizing that some individuals are more talented and artistically-skilled could have been one of the critical contributing factors to art’s early beginnings in human society.16

EVOLUTION OF EARLY HUMANS AND THE BEGINNINGS OF ART

The current practice of all the arts is woven into the fabric of human cultures, but art’s early beginnings were sporadic, patchy, and inconsistent, even when symbolic and abstract cognition was already expressed in other activities.17 Therein lies the challenge in uncovering the origins of art practice: What conditions prevailed when the practice emerged, what conditions led to consistent (as opposed to sporadic) practice, and what conditions have allowed it to endure? Is it alterations in the brain alone due to selective genetic mutations? Alterations in cognition? Evolution of the human brain spans several millions of years if we begin with the divergence of hominins from chimpanzees; that split is estimated based on genetic analysis to have occurred, approximately 4.1–8 millions years ago.18–20 The earliest archaeological and paleontological records for the emergence of human ancestors were found in Africa. Homo sapiens are the only hominins associated with regular art expression and the earliest fossil is dated to around 195,000 years ago and considered to be anatomical modern.

At the same time, some scholars argue that there is evidence for isolated symbolic mentation in an earlier member of the Homo genus, notably Homo erectus, and trace it to 1.7 million years ago, to Africa.21 The tools produced by H. erectus belong to what is known as the Acheulian industry. However, it is not only tool artifacts that bespeak of symbolic cog- nition. Behaviors such as organized hunting habits, cooking, camp site spatial arrangement, use of red ochre, and many other related activities trace their ear- liest appearance to around 300,000 years ago, a time corresponding to the Middle Stone Age in Africa.17,22

Despite a current absence of fossils that point to those traces as belonging to anatomically modern humans,

the possibility that they do belong cannot be ruled out. ‘. . . . African MSA [Middle Stone Age] technology shows logic and inventiveness, and that ecological and economic aspects of the record [archaeological] reflect human innovation, and abstract thought in the form of systematic planning depth, conceptualization of the future, and formalized social relationships among individuals and groups. . . . these features demon- strate a capacity to imbue aspects of experience with meaning, to communicate abstract concepts, and to manipulate symbols as part of everyday life’ (Ref 17, p. 137). Despite all of this, consistent and abundant art-related artifacts are not associated with the MSA, rather, as judged by the archaeological record, art pro- duced consistently and continually appeared hundreds of thousand years later.

Gradual adaptations to the prevailing ecologi- cal and demographic reality of the early anatomically modern humans in the ensuing thousands of years in Africa left behind symbolic behavioral markers including development of social group dynamics.24–26

The latter is considered central to the eventual con- sistent, and enduring, practice of art. Many thousand of years following the emergence of H. sapiens, the climate in Africa changed drastically leading to adap- tive survival strategies: Mega droughts lasting many centuries wreaked devastation on food resources and thus created conditions that forced migration in search of food within the continent.27 Innovative alterations in survival methods resulting from the within-Africa migrations such as those leading to cooperative group living despite increase in group size and inclusion of kin and nonkin in the same group (nonhuman pri- mates live with kin members), fishing as a source for food, new vegetable sources, and to production of art-related artifacts. Use of perforated shells as beads, deliberately incised geometrical patterns with clear lines, application of many different shades of red ochre, long-distance transportation of high-quality goods, were found in the Blombos Cave, South Africa, and dated to around 77,000 ago.23,28 In the western part of South Africa, fragments of engraved ostrich egg shells dated to 60,000 years ago were found.29

Widely spaced human settlements in South African sites close to the coastline reveal distinct technologi- cal industry consisting not only of high-quality stones tools but also of varied tools, namely those made from bones and shells, sharper blades for weapons, spears and arrows, and ground demarcations indicat- ing group-oriented existence.24,30

In addition, archeological information from that time period in South Africa points to social rela- tionships consistent with hierarchical organization, possibly with status, rank, and roles.31–34 The increase

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in size of individual groups and their composition (kin and nonkin in the same group) implies cooper- ation and good survival strategies for the group as a whole.35 Scholars suggest that body decorations and ornaments served a purpose in differentiating group members from other members, in designating social layers (e.g., status), and, importantly, in provid- ing visually identifiable signs.10,16,36 Thus, this social aspect of early human life, rather than mere esthetics, may have been the major contributor to a culture where art expression is valued.

However, the road from Africa to the copious, varied, consistent, and enduring art making, which occurred 45,000–35,000 years ago in western Europe, in a period known as the Upper Paleolithic, was slow and stretched not only years-wise but also continent-wise. That art was not unlike what we are accustomed to see today. It would seem that once a certain high threshold was crossed, art became a valued and an enduring part of human cultural practices. Then it consisted of representational figurines, carved pendants, etched stones, bones, and antlers, shaped wood, pierced beads made of ivory and shells, and various other materials. Significantly, the Upper Paleolithic was a time when there was long-term stability in human population size.37 The scholarly consensus is that the richness and variety reflect cumulative effects of, by then, genetic inheritance of artistic talent, inherited cognition enabling social, cultural, and economic skills acquired in the preceding thousands of years in South Africa and dispersed through migration. This, together with various prevailing favorable European demographic conditions further enabled growth in art practice.17

But humans could not have suddenly reached a cognitive artistic interest that enabled them to create such a wealth of art.22 Brains evolve slowly.38 The cognition had to have been already present.22,24 Some scholars argue that a genetic brain-related mutation enabling abstract cognition sparked this artistic output,39,40 and some propose that this was due possibly to increased food sources rich in lipids.41–43

The view adopted here concurs with the gradual, stretched, yet adaptive evolutionary course view.44

Some questions remain to be investigated: Who were the people who created that Upper Paleolithic art and where did they come from? The current view is that they originated in Africa, and based on archae- ological, genetic, and climatic conditions evidence, spread away from Africa into the rest of the world in multiple trickles45 as well as in major migra- tions. The major migrations are emphasized: The first major migration away from Africa was approxi- mately around 100,000 years ago and the second was

approximately around 60,000 years ago.46 The sec- ond migration ended up being more widespread glob- ally than the first, and it was possibly those humans who brought with them technological, social, and food attainment skills acquired when they adaptively survived the mega droughts in South Africa. They also brought with them their good genes, ones that enabled adaptation and survival. However, judged from the archaeological record (so far), it took another approximately 20,000 years for consistent, continu- ous, and full-blown artistic output in western Europe (the Upper Paleolithic art); additional important con- tributing factors must have prevailed. Those that have been discussed are: Increase in population density, sur- vival of artistically skilled individuals, and passing on skill learning,35,47,48 development of unifying cultural practices,49–51 development of reciprocal altruism,52

increase in complex socially-based interactions depen- dent on symbolic inference,3,16 reactions to interaction with the Neanderthals who were already living in western Europe for approximately 160,000 years and for whom there is some evidence of body decoration and advanced technological skills,16,53–56 and favor- able demographic conditions and implementation of clever hunting and fishing practices.57 All of these, and more (not all the details are known), could have contributed to the adaptive value of art expressions in human culture.

The musical, dance, and theater arts are active, essential, and integral aspects of human cultures today. The archaeological footprints of these forms are largely missing. However, ancient flutes from the Upper Paleolithic period have been unearthed and can be assumed their purpose was to make musical sounds. It is hardly possible that when visual art emerged early on, other forms of artistic expressions did not as well. Indeed, visual art practice could well have been preceded by dance, music, and spoken prose.

BIOLOGICAL ROOTS OF ART

An original idea raised and discussed in the past 30 years or so is that art shares the same exhibitory motivations seen in animals’ courtship displays.58–61

In both, communication between displayer and viewer is key and enormous effort and energy are invested in attraction to the display. Obviously, the communica- tion produced by the brain of the artist is meant strictly for the brain of the human viewer. The purpose of the exhibit in the first place is rooted in Darwin’s sexual selection evolutionary concepts.62,63 With animals, the display is a platform for exhibiting fitness and high genetic qualities (that promote survival) to potential mates so that those will be reproduced in surviving

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offspring; with artists, the display is a platform for exhibiting cognitive depth, talent, skill, and creativity all of which reflect the artistic-related genetic quality. Artists spend enormous energy creating their works, spending weeks, months, even years on a single art endeavor. What is their motivation for doing so? Ani- mals expand tremendous physical energy maintaining display traits as well as display rituals, often at great costs to their survival. Both art and animal courtships are costly energy expanders. Both are showcases for genetic quality, although artists are not directly dis- playing in order to attract a mate; they are attracting the viewer to their art (but see Refs 64 and 65). The art reflects quality of brain, mind, cognition, and genetics of the artist through culturally accepted behavior, and in this way the art is an identifying symbol of the culture or group in which it was created.

Art, as courtship displays, is interpreted best when the context within which it was expressed is known. What artists create and display is their reactions to ongoing internal and external happenings, ideas, and emotions. The Impressionists would not have produced fuzzy paintings if it were not for their rebellious reaction against the preceding realism of linear perspective that dominated European art since the Renaissance; Mondrian would not have drawn straight intersecting lines if it were not for the influence of Abstract art artists who moved even further away from the Impressionist style of depicting reality and closer to the Dada and Surrealistic schools; Debussy, Stravinsky, and Copland moved away from the musical tonal tradition that dominated in the 19th century; modern dance choreographers Isadora Duncan and Rudolf von Laban reacted to the classical ballet routines. Art works reflect artists’ reactions to their experiences, whether in caves in South Africa or in Altamira, or in a studio in Paris. Moreover, artists in a given culture can be influenced by art created in distant cultures. The art of Picasso, Modigliani, Van Gogh, Degas, and many more, including choreographers, musicians, poets, and novelists, at the end of the 19th and beginning of the 20th centuries in Europe shows the influence of art created thousands of miles away, in Pacific Ocean islands and Africa.66

These artists resonated to cultural works other than their own and acknowledged it. The underpinning of this influence is the biological–neurological communicative nature of art.

Beauty is an important attractant to works of art. How are esthetic reactions to art related to the biological roots discussed above? Do we think a beau- tiful painting is one where we subconsciously ‘see’ the talent, skill, and cognition of the artist that we infer to be of relevant genetic quality? Or is that subconscious

assessment not part of the beauty response at all? We do not know whether or not beauty reactions are uniquely human experiences, for example. In fact, beauty applies to many things: to ideas, words, nature scenery, faces, as well as to art. Nevertheless, neu- roanatomical pathways in the brain have been linked to beauty-related reactions to paintings,67–69 although it has not yet been worked out whether or not different sources of beauty share the same or different neural pathways. The fact that headway has been made in identifying some of these pathways brings us a step closer to some of the biological underpinnings of art.

While there seems to be a behavioral interaction between how beautiful a work of art appears and the attraction to it, artists do not ‘place beauty’ in their art, rather the viewer’s mind extracts the beauty, or lack of it (ugliness, say). Beauty reactions are an emergent property in the brain of the audience. While esthetics draw attention to art so as to consider its contents this does not necessarily mean that all of art is deemed beautiful. We seem to consider art for its own sake, not just for its beauty appearance, and for this reason there is lack of universality in esthetic reactions to art (unlike the universality in reactions to facial beauty). Art can be deemed beautiful if the culture in which it was created considers it good, for example. Different brain areas are active in response to beautiful versus ugly in pictures (not paintings).70 When, for example, nonartist subjects viewed paintings they considered ‘ugly’ as opposed to ‘beautiful’, the amygdala in the brain was maximally active.69 Several different regions responded actively to ‘beautiful’. The amygdala is linked to emotional modulations and to fearful responses; bilateral damage to the amygdala results in diminished fear responses as well as in diminished capacity to recognize fear in others.71,72 It would appear, then, that neuroanatomical structures (the amygdala and its related circuitry) that evolved for many millions of years to trigger a fear response for protection from predators are now active in nonnaturally occurring artifacts such as art works.

Nowhere are the social and biological underpin- nings of art more obvious than in music.73–75 Studies in which human music making and animal songs have been compared revealed profound similarities, not only in qualities such as rhythm, pitch, and length, but also in the intention, specifically in communicating a message to con-specific listeners that elicits physiolog- ical reactions associated with emotions. Indeed, the association between music listening and genetic mark- ers for social attachment has been reported,51,76 and the theoretical suggestion that the hormone oxytocin, which is linked to forming attachments, is somehow also involved in attraction to art has been made.44

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NEURAL UNDERPINNING OF ART: EVIDENCE FROM BRAIN DAMAGE AND FUNCTIONAL NEUROIMAGING

Traditionally, the link between neuroanatomical structures and their functions has been inferred through observations of behavioral consequences of brain damage. In this regard, much of what we know about the consequences of brain damage in artists is based on visual artists. Basically, once there is damage to the brain, artists exhibit similar perceptual and cognitive impairments as nonartists.77,78 Damage in the right parietal lobe, for example, frequently results in hemi-neglect of the left half of space79; neurological patients omit details in their left half of space, fail to eat food on the left half of the plate, and so on. Artists fail to complete necessary details in the left half of their paintings. The symptoms frequently last approximately 6–8 weeks, or in some cases, longer than that. Damage in the right parietal lobe can also results in impaired spatial cognition (e.g., spatial layout, diagrams, topography). The impairment can be discerned as distortions in art. When the damage is localized in the left lingual gyrus (which spans the occipital and temporal lobes) alterations in color use can be expected.10 However, the fact that both artists and nonartists show the same behavioral consequences of brain damage suggests that when the distortions and alterations are seen in post-damage art, they do not reflect deficits in art cognition per se.

With artists, we ask what aspects of the work become impaired, what aspects go unchanged? Reviewing approximately over 40 visual artists with brain damage revealed that regardless of the brain region that had been damaged, and, importantly, regardless of its laterality (left or right hemisphere), artists continue to produce their art, they do not change their genre even as their techniques are altered due to affected motoric control of the arm, or acquired visual or perceptual problems.10 They remain abstract painters if they were that before, figurative painters if they were that before the damage. Similarly, skill and creativity do not diminish regardless of hemispheric damage lateralization or localization within a hemi- sphere. Techniques sometimes do change post-damage particularly if the damage involves the motor cortex, because of altered control over manual crafting tools, and stylistic alterations in 2 patients with Alzheimer’s disease have been attributed to other reasons.80,81

Artists with diffuse brain damage in diseases such as Alzheimer’s or fronto-temporal dementia continue to produce art for many years into their illness, a time when their language abilities show severe disruption or complete deterioration.82,83

This pattern reveals a neuroanatomical dissociation between the communicative underpinning of art and language. The former is preserved despite extensive neuronal loss while the latter is highly sensitive to neuronal loss (language is cerebral hemisphere- and region-specific). Similarly, profound brain damage, such as seen in autism, can in a select few individuals with the condition, spare regions that support artistic talent.84 They are known as savants. We do not yet know what those spared regions might be, but it is hardly possible that the damage itself gives rise to the observed talent, or else artistic savant cases would not be so rare. In sum, communication through art appears to involve multiple brain regions and pathways.

BRAIN, VISUAL ART, PERCEPTION, AND COGNITION

Colors and visuospatial cognition have been identified as important components of visual art. Colors are applied extensively to enhance, emphasize, and attract the viewer.7,9 What evolutionary explanations underlie artists’ choice in color palette and viewers’ preferences? A tantalizing theory proposed just a few decades ago and known as the savanna hypothesis suggests that the current human color visual preference developed when the anatomically modern H. sapiens emerged in East Africa where the environment was dominated by the savannah landscape with its characteristic colors.13,85–87 In addition, then as now, colors have come to have distinct symbolic meanings. Shades of red derived from different sources of red ochre were already used in Africa at least 90,000–70,000 years ago.25

In the brain, color cognition critically depends on the integrity of the lingual gyrus in the left hemisphere; damage in that brain region leads to color agnosia, the loss of knowledge of the meaning of colors78 and small regions in the occipital-temporal lobe junction of both hemispheres process chromatic features of objects. However, the fact that color-blind (or color deficient) artists can produce highly regarded paintings and drawings shows that colors are not an essential feature of visual art88; colors are another dimension of art and are just another way of expressing a particular artistic skill. Indeed, many art forms do not require colors (e.g., drawings, etchings, photography, cinema); colorful paintings incorporate shades of gray to depict shadows and depth, and viewers are nevertheless attracted to viewing these works.

Visuospatial cognition is another component of art tied to specific brain regions. It consists of knowledge of layouts, terrains, and maps, mental manipulation of images in the mind’s eye, translation

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from mental imagery into real space, depiction of depth in 2- or 3-dimensional space, use of diagrams to construct, and the ability to fashion realistic statuettes and sculptures from raw material. However, not all art forms require the same type of spatial cognition (e.g., abstract art). Artists before the Renaissance had not discovered linear perspective although they applied spatial cognition without it. In the European cave art they used figure overlap, size variations, and shadows. Realistic figures were shaped from ivory, wood, bone, and stone. Similarly, spatial cognition is required in constructing stone tools whether by H. erectus or early H. sapiens. Right hemisphere specialization for spatial cognition was once viewed as an essential component in both producing and perceiving the art, but because of meager supporting evidence the right hemisphere and art connection is now viewed as outdated.89,90

Indeed, as mentioned in the previous section, evidence from brain damage in artists points to the involvement of both hemispheres in art production.

CONCLUSIONS

Referential, symbolic, and abstract cognition estab- lishes the foundation for human communication in language and art. Art, in all its forms and mediums, is a communicative system that gained momentum at its

beginnings because of social–cultural developments in the life of early H. sapiens, in Africa. However, the capacity for symbolic cognition was present hundreds of thousands of years before H. sapiens began to prac- tice art consistently. The critical triggers for art are hypothesized to be visual social identifiers rather than mere esthetics. Art’s practice eventually became sub- ject to selection pressures that expanded its multiple expressions in innovative and enduring ways.

Energy-consuming efforts into producing art are likened to courtship rituals in animals, where the motivation is to display physical and genetic quali- ties (to attract mates and ensure survival of offspring). Humans invest much energy in displaying their artistic talent (genetic), skill, and cognition in order to com- municate and perpetuate art’s cultural practice. The biological underpinnings of art might also explain why artistic talent is highly resistant to neuronal damage, unlike the sensitivity of language or perception to neu- ronal damage. Even when there is a profound brain dysfunction as is the case with autism, a select few individuals with the condition do display remarkable artistic talent. In sum, art is produced spontaneously only by humans and has developed adaptively to serve humans as a culturally cohesive tool practiced ubiquitously throughout the world.

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