Note: It is highly recommended that you read So What’s With Jane already? A Primer on Pictorial Composition. (Part I) , “To the makers of music – all worlds, all times.” A Primer on Pictorial Composition. (Part II) , Henri Breuil and Alfred Yarbus Walk into a Bar…A Primer on Pictorial Composition. (Part III), A Spurious Affair. A Primer on Pictorial Composition. (Part IV), Fool’s Gold. A Primer on Pictorial Composition. (Part V), and Getting organized…A Primer on Pictorial Composition (Part VI) before embarking on this installment.

“How often people speak of art and science as though they were two entirely different things, with no interconnection. An artist is emotional, they think, and uses only his intuition; he sees all at once and has no need of reason. A scientist is cold, they think, and uses only his reason; he argues carefully step by step, and needs no imagination. That is all wrong. The true artist is quite rational as well as imaginative and knows what he is doing; if he does not, his art suffers. The true scientist is quite imaginative as well as rational, and sometimes leaps to solutions where reason can follow only slowly; if he does not, his science suffers.” — Isaac Asimov “Prometheus”, The Roving Mind (1983)

“I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I’ll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be.“ —Isaac Asimov, The Roving Mind (1983)

It is unfortunate that during a time when the dissemination of information is the greatest it has been in human history, there still exists deliberate efforts to insulate oneself from scientific concepts that could potentially provide great insight into one’s area of practice. I have spent many years trying to introduce contributions from present-day science into the art classroom only to find that some perceive the arts and sciences as components of a zero-sum game.  Obviously, this could not be further from the truth. However—I do understand why some might see certain scientific concepts as unwelcome guests in the studio.  Freelance writer Philip Ball effectively explores one of the perceived hazards of the merging of modern science and art in a 2013 Nature Magazine article:

“For one thing, to suggest that the human brain responds in a particular way to art risks creating criteria of right or wrong, either in the art itself or in individual reactions to it. Although it is a risk that most researchers are likely to recognize, experience suggests that scientists studying art find it hard to resist drawing up rules for critical judgements. The chemist and Nobel laureate Wilhelm Ostwald, a competent amateur painter, devised an influential theory of colour in the early twentieth century that led him to declare that Titian had once used the ‘wrong’ blue. Paul Klee, whose intuitive handling of colour was impeccable, spoke for many artists in his response to such hubris:

“That which most artists have in common, an aversion to colour as a science, became understandable to me when, a short time ago, I read Ostwald’s theory of colours … Scientists often find art to be childish, but in this case, the position is inverted … To hold that the possibility of creating harmony using a tone of equal value should become a general rule means renouncing the wealth of the soul. Thanks but no thanks.”

-Philip Ball, Neuroaesthetics is Killing your Soul, Nature, March 2013.

Now while this short excerpt may initially seem to demonstrate a valid concern for some, a closer look may reveal some faults in the argument.  For example, Ball states that “to suggest that the human brain responds in a particular way to art risks creating criteria of right or wrong, either in the art itself or in individual reactions to it. Although it is a risk that most researchers are likely to recognize, experience suggests that scientists studying art find it hard to resist drawing up rules for critical judgments.”  This may not come as a surprise to most of you, but we already contend with a significant amount of restrictive criteria as well as rules for critical judgment when eliciting information from the visual world. Biologically speaking, human vision is limited to a very narrow band of the electromagnetic spectrum and requires a level of contrast above our minimum contrast sensitivity as well as a stimulus that is on a scale within the limits of our angular resolution. If we deviate from these parameters within a visual arts endeavor, we will fail to create something that can be experienced visually.  At that point, further consideration is moot.

As to critical judgments, I believe that I can safely state that humans are already well versed in their use. The ability or propensity to make critical judgments is not something new that science is about to spring on the art world from out of the blue. What science can offer is information to make more informed judgments.  Funny enough, two sentences after Ball warns us of the impending threats from critical judgment, he himself falls prey to temptation by deeming Paul Klee’s intuitive handling of color to be “impeccable.”

Klee’s response to Ostwald featured in Ball’s article further promotes this apparent pseudo-incompatibility between science and art. While I am not advocating for any of Ostwald’s ideas, Klee’s response does seem to be hyperbole resulting from an attempt to cram an analog concept into a digital filter.  Additionally, I am not sure how to begin to adequately address the claim that a general rule may be responsible for “renouncing the wealth of the soul”.

Further increasing anxieties regarding the infiltration of art by the sciences are satirical efforts like the “People’s Choice” project carried out by Russian-born American artists Vitaly Komar (1943-) and Alexander Melamid (1945-) in the mid to late 1990s. The project involved the conducting of scientific polls in 11 countries to discover aesthetic preferences in painting. Taking the aggregate results, the artists then produced works dubbed The Most Wanted and The Least Wanted from each country. With this effort, Komar and Melamid felt that they could determine what art would look like if it were designed by committee to please the greatest number of people. In a publication following the project, Komar said, “Our interpretation of polls is our collaboration with various people of the world. It is a collaboration with a[sic] new dictator—Majority.” -Wypijewski, JoAnn, ed. Painting by Numbers: Komar and Melamid’s Scientific Guide to Art, New York: Farrar Straus Giroux, 1997.

The most favored painting from the People’s Choice project was a mostly-blue landscape with water, people, and animals while the least favored painting was an abstract design of jagged shapes featuring a thick impasto and the disliked colors of gold, orange, and yellow.

You can see the full survey results here: http://awp.diaart.org/km/surveyresults.html

And a gallery of the resulting work here: http://awp.diaart.org/km/painting.html

As you might suspect, the “scientific” survey was problematic, and the resulting paintings were–well–just plain bad (and yes, I am making a critical judgment here). The artists muddled important factors (including aesthetic preference and individual taste) and produced a collection of works that most roadside motels would be hesitant to hang.  But it was not the mere muddling of factors that produced the less-than-stellar artworks–it was the idea that a component preference in one context could transfer such qualities to an aggregate in another. The philosopher Denis Dutton offered this comparison in regards to the efforts of Komar and Melamid, “Let’s imagine offering to discover for Americans their Most Wanted Food. To be accurate and avoid inappropriate elitism, we do a careful, demographically adjusted survey of gustatory preferences, hiring the Gallup organization to conduct scientific polls, renting church halls for focus groups (videotaped), and talking to everyone who wants to be heard. It’s expensive, to be sure, but we manage to persuade a respectably liberal nonprofit foundation to fund our research — after all, we’re finding out what the people want. As the results come in, we discover that Americans’ tastes in food are wide-ranging, whimsical and imaginative, often traditional, but also ethnic in every direction. Despite the vast variety, however, we determine that numerically dominating the food taste list are preferences for hamburgers, pizza, ice cream, and chocolate. So we put our culinary skills to work and come up with the ultimate dish. Here, America, is your Most Wanted Food: hamburger-flavored ice cream with chocolate-coated pizza nuggets. Eat it!”

Now don’t worry—I do not plan to continue down this path at present. I have no intention of thoroughly exploring the psychology of what makes some people more or less resistant to the ongoing contributions from modern day scientific research.  Such a complex topic is far beyond the scope of this series. What I would like readers to appreciate, though, is that there are indeed many areas of modern research (empirical aesthetics, neuroaesthetics, vision science, cognitive psychology, evolutionary psychology, etc…) that can offer AMAZING insight into the art experience.  Can scientific insights be misapplied to aspects of the creative process? Of course–but you don’t throw out the arithmetic book when someone gets a math problem wrong.

Rather, with the last installment of this primer, I would like to pull together the many concepts that we have explored thus far into one cohesive map of considerations for the navigating of pictorial composition. While I will present what I hope is a clear overview of each entry on the map, I strongly encourage you to research these ideas further. This map, like this primer, is a starting point for a truly productive exploring of this complex topic. The map is not a shortcut or a heuristic. There are no mystical numbers or magical devices to be found. And as with most fruitful educational resources, it will require some work on the reader’s part to make the most of it.

Biology

Our map begins with the one factor that determines our ability to elicit visual information, experience aesthetic qualities, and engage in communication–our biology.  As we have explored in the previous installments of this series (as well as earlier in this installment), human vision is limited to a very narrow band of the electromagnetic spectrum and requires a level of contrast above our minimum contrast sensitivity as well as a stimulus that is on a scale within the limits of our angular resolution. These biological parameters are paramount, and as stated earlier, a stimulus existing outside these parameters will fail to be perceived–at which point further consideration is moot.

Context

Dejan Todorović wrote in the 2010 Review of Psychology: “In our everyday perception, when we look at an object, intuitively it seems obvious that what we are aware of are just the properties of that object itself, and not of something else, beyond the object. However, contextual effects do exist, ranging from weak but noticeable to strong and perplexing, and present major challenges to our understanding of the working of perceptual mechanisms and cognitive processes in general.”

Context influences our perceptions of geometry, value, color, depth/form as well as more complex perceptual tasks like object recognition.  For example, we may perceive the length of a particular line quite differently as the surrounding context of the line is altered (both red lines are physically identical in length.)

Let’s look at a few examples of how context influences what we see:

Some contextual influences can be controlled by the artist while others cannot.  For example, while the artist may be able to control all of the elements within a work of art, he or she may have no control over the manner in which the work may be used or exhibited. The manner of use or exhibition may significantly influence the way in which the image is perceived or how well the work may communicate meaning.  Therefore, if you can garner knowledge of how your work may be used or exhibited, it will allow you to make better decisions regarding composition.

Bias

Bias can be described as a biological predilection as well as a particular tendency, trend, inclination, feeling, or opinion, especially one that is preconceived or unreasoned.  While some biases may be derived from a biological imperative–others are learned from experience (e.g., implicitly within cultural context.) Cognitive biases can be considered heuristics or cognitive shortcuts–sometimes leading us to irrational conclusions–but sometimes serving an adaptive purpose (e.g., allowing us to reach decisions quickly in situations when time is of the essence.) As you will soon see, the aesthetic qualities that we experience are ultimately a collection of biases.

Perceptual Set/Priming Effects

Two additional high-level variables are perceptual set and priming effects. While controlling these factors may often be beyond the reach of the artist–knowledge of your target audience may allow you to predict these variables with reasonable success.

Perceptual set is an observer’s tendency to perceive or notice some aspects of the available sensory data and ignore others.  It has been found that a number of variables, or factors, influence perceptual set, and set in turn influences perception. The factors include expectations, emotion, motivation, and culture. In 1955, American psychologist Gordon Willard Allport defined perceptual set as: “A perceptual bias or predisposition or readiness to perceive particular features of a stimulus.”

Another strong demonstration of the influences of context and perceptual set was presented in my first installment, So what’s with Jane already? A Primer on Pictorial Composition. (Part I):

See if you can “read” the following text:

The quote from Shakespeare (“a rose by any other name would smell as sweet”) contains the letter grouping sm l in the sentence which could easily become the word smile instead of the word smell. I would think it may be reasonable to suspect that an aesthetic “word-preference survey” could easily yield that, independent of context, the word smile would find aesthetic preference over the word smell (as the concept for the former may be generally more attractive than the latter for a number of biological reasons), but in the above context, if your past experience warrants, your brain opts for smell over smile.

The same holds for the more common pop-culture phrase made famous by the popular Star Wars franchise (“may the force be with you”). You can just as easily fit in the word peace instead of force. Again, you can probably conduct a survey to find that more people would prefer the word peace over the word force in isolation, without supporting context (as we have seen with the above efforts of artists Komar and Melamid)–however, we again find the potential aesthetic preference of an individual variable surpassed by context.

On the influence of culture on perceptual set, psychologist and author Saul McLeod writes,

“Deregowski (1972) investigated whether pictures are seen and understood in the same way in different cultures. His findings suggest that perceiving perspective in drawings is in fact a specific cultural skill, which is learned rather than automatic. He found people from several cultures prefer drawings which don’t show perspective, but instead are split so as to show both sides of an object at the same time.

In one study he found a fairly consistent preference among African children and adults for split-type drawings over perspective-drawings. Split type drawings show all the important features of an object which could not normally be seen at once from that perspective.  Perspective drawings give just one view of an object. Deregowski argued that this split-style representation is universal and is found in European children before they are taught differently.

Hudson (1960) noted difficulties among South African Bantu workers in interpreting depth cues in pictures. Such cues are important because they convey information about the spatial relationships among the objects in pictures. A person using depth cues will extract a different meaning from a picture than a person not using such cues.

Hudson tested pictorial depth perception by showing participants a picture like the one below. A correct interpretation is that the hunter is trying to spear the antelope, which is nearer to him than the elephant. An incorrect interpretation is that the elephant is nearer and about to be speared. The picture contains two depth cues: overlapping objects and known size of objects. Questions were asked in the participants native language such as:

What do you see?

Which is nearer, the antelope or the elephant?

What is the man doing?

The results indicated that both children and adults found it difficult to perceive depth in the pictures.

The cross-cultural studies seem to indicate that history and culture play an important part in how we perceive our environment. Perceptual set is concerned with the active nature of perceptual processes and clearly there may be a difference cross-culturally in the kinds of factors that affect perceptual set and the nature of the effect.”  -Saul McLeod, Perceptual Set, SimplyPsychology.org

I briefly touched on the issue of cultural influences on pictorial communication in “To the makers of music – all worlds, all times” A Primer on Pictorial Composition. (Part II):

The concept of a ‘picture’ is by no means universal, not even on our own planet. Let us not forget the curious story from Henri Breuil, a French Catholic priest and amateur archaeologist, which describes a Turkish officer who was incapable of recognizing a drawing of a horse, “because he could not move round it.” Being a Muslim, the officer was entirely unfamiliar with depictive art. Such stories could easily lead many to argue that the eliciting of meaning from a two-dimensional representation is not an innate human ability.

The third installment of this series, Henri Breuil and Alfred Yarbus Walk into a Bar…A Primer on Pictorial Composition. (Part III), explored this idea even further:

“Data collected among the Baganda of Uganda indicates that pictorial perceptual skills are positively and significantly related to relative amounts of exposure to Western culture. Both urban and relatively more acculturated rural residents make overall more correct identifications of pictorial objects and more consistent use of cues to pictorial depth than more traditional Baganda. These results offer support for the proposition that visual perceptual skills are related to culturally constituted experience.” -Kilbride, Philip L., and Michael C. Robbins. “Pictorial depth perception and acculturation among the Baganda.” American Anthropologist 71.2 (1969): 293-301.

“Reports of difficulty in pictorial perception by members of remote, illiterate tribes have periodically been made by missionaries, explorers, and anthropologists. Robert Laws, a Scottish missionary active in Nyasaland (now Malawi) at the end of the 19th century, reported: “Take a picture in black and white and the natives cannot see it. You may tell the natives, ‘This is a picture of an ox and a dog,’ and the people will look at it and look at you and that look says that they consider you a liar. Perhaps you say again, ‘Yes, this is a picture of an ox and a dog.’ Well, perhaps they will tell you what they think this time. If there are a few boys about, you say: ‘This is really a picture of an ox and a dog. Look at the horn of the ox, and there is his tail!’ And the boy will say: ‘Oh! Yes and there is the dog’s nose and eyes and ears!’ Then the old people will look again and clap their hands and say, ‘Oh! Yes, it is a dog.’ When a man has seen a picture for the first time, his book education has begun.” -Deregowski, Jan B. “Pictorial perception and culture.” Scientific American(1972). Nov.:82-88.

Priming is an implicit memory effect in which exposure to one stimulus influences the response to another stimulus. It can occur following perceptual, semantic, or conceptual stimulus repetition. For example, if a person reads a list of words including the word table, and is later asked to complete a word starting with tab, the probability that he or she will answer table is greater than if they are not primed.

There are several types of priming and the effects can be very salient and long lasting. Unconscious priming has been shown to affect word choice on a word-stem completion test long after the words have been consciously forgotten.

Priming works best when the two stimuli are in the same modality. For example, visual priming works best with visual cues and verbal priming works best with verbal cues. But priming also occurs between modalities, or between semantically related words such as “doctor” and “nurse”.

The influence of such effects can be seen with the eye-tracking work of Russian psychologist Alfred Yarbus (another scientists whose work was referenced throughout this series). In his 1967 work, Eye movements and vision,  Yarbus writes, “Depending on the task in which a person is engaged, i.e., depending on the character of the information which he must obtain, the distribution of the points of fixation on an object will vary correspondingly because different’ items of information are usually localized in different parts of an object. This is confirmed by Fig. 109. This figure shows that, depending on the task facing the subject, the eye movements varied. For example, in response to .the instruction “estimate the material circumstances of the family shown in the picture,” the observer paid particular attention to the women’s clothing and the furniture (the armchair, stool, tablecloth, and so on). In response to the instruction “give the ages of the people shown in the picture,” all attention was concentrated on their faces. In response to the instruction “surmise what the family was doing before the arrival of the ‘unexpected visitor,'” the observer directed his attention particularly to the objects arranged on the table, the girl’s and the woman’s hands, and to the music. After the instruction “remember the clothes worn by the people in the picture,” their clothing was examined. The instruction ‘remember the position of the people and objects in the room,” caused the observer to examine the whole room and all the objects. His attention was even drawn to the chair leg shown in the left part of the picture which he had hitherto not observed. Finally, the instruction ‘estimate how long the ‘unexpected visitor’ had been away from the family ,” caused the observer to make particularly intensive movements of the eyes between the faces of the children and the face of the person entering the room. In this case he was undoubtedly trying to find the answer by studying the expressions on the faces and trying to determine whether the children recognized the visitor or not.”

Records of the eye movements after an instruction are interesting because they help in the analysis of the significance of eye movements during the free examination of a picture; they show clearly that the importance of the elements giving information is determined by the problem facing the observer, and that this importance may vary within extremely wide limits.

…In conclusion, I must stress once again that the distribution of the points of fixation on an object, the order in which the observer’s attention moves from one point of fixation to another, the duration of fixations, the distinctive cyclic pattern of examination, and so on are determined by the nature of the object and the problem facing the observer at the moment of perception.” -Yarbus, A. (1967). Eye movements and vision (B. Haigh & L. A. Riggs, Trans.). New York: Plenum Press

So while Bias, Perceptual Set and Priming may seem an uncontrollable variable in many cases, knowing something about how your work may be displayed and potential audience that may view it (e.g., if the work will be used to illustrate a story, featured in a publication that holds a special focus, exhibited in a showcase with a particular theme) can allow you to make some informed, reasonable assumptions regarding all three during the composition phase of your work.

It is here that the map splits into two main categories that can be found in our initial definition of pictorial composition:

Pictorial composition can be defined as the specific content of an image as well as the spatial relationship of its elements with respect to aesthetic quality and communication efficacy.

Communication

Thoroughly exploring a topic as complex as human communication would require an effort that is far beyond the scope of this paper.  Rather, I would like to introduce the aspects of it that I consider applicable to our focus here (visual communication).  As such we can define communication here simply as the act of conveying intended meanings/information from one entity or group to another through the use of mutually understood signs and semiotic rules. More specific to our focus, visual communication is the communication of ideas via the visual display of information.

Some would argue that visual communication is the type of communication that people rely on most.  This might make sense as nearly 30% of the human cortex is dedicated to vision (compared with 8% percent for touch and just 3% percent for hearing.)

When I am considering the “communication” aspects of a work, I am thinking about what information I am intending to pass on to the viewer. I need to consider:

What conventions (signs/symbols/representations) of visual communication will be most effective for my purposes?

How might bias, priming effects, and perceptual set affect those conventions?

How will those conventions be affected by my aesthetic considerations?

While our map of considerations separates communication and aesthetic qualities, there will indeed by overlap. In fact, you may discover that some consideration points may apply to both categories (metaphor, for example, can be a communication consideration as well as an aesthetic one.)

A more formal breakdown of my considerations of visual communication can be understood by the rules of semiotics. Semiotics is the study of meaning-making, the study of sign processes and meaningful communication. This includes the study of signs and sign-using behavior, indication, designation, likeness, analogy, metaphor, symbolism, signification, and communication.

Semiotics is closely related to the field of linguistics, which, for its part, studies the structure and meaning of language more specifically. The semiotic tradition explores the study of signs and symbols as a significant part of communications. As different from linguistics, however, semiotics also studies non-linguistic sign systems.

The type of communication that I am concerned with can be seen as processes of information transmission with three levels of semiotic rules:

Pragmatic (concerned with the relations between signs/expressions and their users)

Semantic (study of the relationships between signs and symbols and what they represent)

Syntactic (formal properties of signs and symbols).

These levels translate to my process as:

Pragmatic (What context can I build from visual elements and design principles to facilitate meaning and minimize apparent ambiguity?)

Semantic (What “meaning” can I create with visual stimuli and what visual relationships can I create between visual elements and design principles to facilitate recognition and maximize the chances for the successful transmission of information?)

Syntactic (What conventions of visual perception and cognition can I make use of to reduce ambiguity and maximize the chances for the successful transmission of information?)

To further explore some ideas about communicating visually I would turn your attention to the second installment of this series, “To the makers of music – all worlds, all times” A Primer on Pictorial Composition. (Part II).

Aesthetics

Moving to the other side of our consideration map we find our considerations for those qualities that are characteristics of a stimulus that elicit adaptive responses that have evolved to reinforce or discourage specific behaviors. As presented in my first installment of this series, we may prefer one type of sensory experience over another—describing one as repulsive and the other beautiful. However, aesthetic qualities should not be confused with individual tastes. Many refer to aesthetic properties as personal preferences and this, I believe, is a serious mistake. Like most concepts involving evolution, concepts of “aesthetics” and “beauty” seems to be most productive when considered on the level of populations and not the individual. For example, it is not as relevant to our goals here that someone may prefer Vanilla over Chocolate—but rather, to consider the overall biological predilection for fat and sugar.

So let’s take a look at the different biases that define our aesthetic preferences:

Spatial Biases/Aesthetics

It is important to note that the following biases exist relative to a frame. This frame may be any closed region of the visual field, or, in some cases, the visual field itself.  For our purposes, we will be primarily considering the frame to be the image area of a two-dimensional artwork.

From Jonathan Sammartino Gardner & Stephen E. Palmer’s 2010 VSS presentation: Representational Fit in Position and Perspective: A Unified Aesthetic Account: “Previous research on aesthetic preference for spatial compositions has shown robust and systematic preferences for object locations within frames, such as the center bias, the inward bias, and various ecological biases (Palmer, Gardner, & Wickens, 2008; Gardner & Palmer, VSS-2006, VSS-2008, VSS-2009). These preferences can be dramatically altered, however, by changing contextual meaning through different titles for the same picture (Gardner & Palmer, VSS-2009).”

Horizontal (Inward Bias): Studies have demonstrated that when an object with a salient “front” is placed nearer the border of a frame than a center, observers tend to find the image more aesthetically pleasing if the object faces inward (toward the center) than if it faces outward (away from the center) (Chen et al., 2014) . I believe that this may have much to do with the idea of understanding our brain as a “prediction machine”. Again, “A still photograph of an object in motion may convey dynamic information about the position of the object immediately before and after the photograph was taken (implied motion)” -(Kourtzi and Kanwisher, 2000). If we can see more of where an object may be “headed”, we can make a better prediction about a future state of the objects being observed.

Horizontal (Center Bias): In studies regarding front-facing subjects, preference was greatest for pictures whose subject was located at or near the center of the frame and decreased monotonically and symmetrically with distance from the center (Palmer, Gardner & Wickens, 2008). The reason that people prefer the object’s salient front region to be as close to the center as possible may result from a number of factors. The greatest influence MAY come from the way in which we usually engage with what we see as a front-facing subject. This center bias may reflect an advantageous viewing position for extracting information from such scenarios. I would like to note here that center bias is not the same that as central fixation bias. They may be related in some way, but not in a way that I can show support for at this time. Central fixation bias is a tendency for observers to begin an exploration of a visual scene at the center. Numerous visual perception experiments have borne this out (e.g., Buswell, 1935, Mannan et al., 1995, Mannan et al., 1996, Mannan et al., 1997, Parkhurst et al., 2002 and Parkhurst and Niebur, 2003). The prevalence of central fixation bias suggests that it is a key feature of scene viewing, but the basis of this effect remains poorly understood.

VSS 2012 Poster-Effects of object facing direction and implied motion on preferences for spatial composition by Thomas A. Langlois, Jonathan Sammartino, & Stephen E. Palmer

Vertical (Ecological Bias): Current research has shown both center and inward biases do in fact influence preferences in the vertical dimension (Sammartino and Palmer, in press). However, such biases in the vertical dimension seem to be different from those in the horizontal dimension. Palmer and Sammartino write, “The inward bias in the vertical dimension differs from that in the horizontal dimension, however, in that it arises for different objects rather than different facing directions of the same object: a lower bias for a bowl and swimming stingray versus an upper bias for a light fixture and a flying eagle. The inward bias in the vertical dimension appears to arise from multiple relatively high-level factors, including what we call functional asymmetry effects, ecological effects, and possibly perspective effects.” -Sammartino, J., Palmer, S.E. (2012). Aesthetic issues in spatial composition: Effects of vertical position and perspective on framing single objects. Journal of Experimental Psychology: Human Perception and Performance, 38(4), 865-879.

Research into spatial preferences in the vertical dimension also point to ecological effects (possibly arising from fluency bias) that seem to be contributing to certain preferences. These effects are referred to as ‘ecological’ because they appear to be driven by people preferring images in which the spatial properties of the image of the depicted object within its frame fit the ecological properties of the physical object relative to the viewer.

Palmer and Sammartino again write, “Ecological effects are based on the fact that some objects tend to be located higher than the observer in the environment (e.g., flying eagles and light fixtures) and others tend to be located lower (e.g., bowls and swimming stingrays).  It appears to cause strong and pervasive inward height biases in the present results in that people prefer the vertical position of an object within the frame to be consistent with the vertical position of the object relative to the observer: i.e., eagles and light fixtures to be high and bowls and stingrays to be low.” -Sammartino, J., Palmer, S.E. (2012). Aesthetic issues in spatial composition: Effects of vertical position and perspective on framing single objects. Journal of Experimental Psychology: Human Perception and Performance, 38(4), 865-879.

VSS 2008 Poster-Representational Transparency in Aesthetic Judgments of Spatial Composition: Effects of Object Position and Size by Jonathan Sammartino Gardner and Stephen Palmer

Affordances

Affordance spaces in regard to pictorial composition are the regions surrounding an object that could allow for object function or interaction. These regions seem to contribute to prediction tasks as well as recognition and categorizations tasks.

“What we are calling functional asymmetry effects would arise because people’s interactions with many objects are not equally distributed over the space surrounding them.  The fact that fronts of objects are almost always more salient in interactions than their sides and backs can explain the inward bias found by Palmer, Gardner, and Wickens (2008) in the horizontal placement: people prefer the more salient functional parts of the object to be closer to the center.

A simpler and more elegant explanation of the results can be devised by positing the existence of what we will call an “affordance space” around an object that reflects the extent and/or importance of functions that take place in that region around the object, where “affordances” are the functions of an object that an observer can perceive from its visible structure (Gibson, 1977).  If the affordance space around an object is asymmetrical, as suggested above, then what we are calling an inward bias may actually be understood as a center bias that operates on an asymmetrical affordance space that contains more surrounding area on the functionally more salient side(s).  That is, if viewers implicitly prefer the affordance space around an object to be centered in the frame, and if that affordance space is asymmetrical with more space in front of horizontally facing objects (e.g., a person, chair, or vehicle), on top of “upward facing” objects (e.g., a bowl), and toward the bottom of “downward facing” objects (e.g., a light fixture), then at least some of the inward biases in both horizontal and vertical dimensions we have found may actually be understood as center biases operating on affordance spaces rather than as inward biases operating on the objective boundaries of the physical objects.  We are currently devising ways to measure the shapes of affordance spaces for different objects empirically to find out whether the results conform to the inward biases we have found in aesthetic judgments of spatial composition.” -Sammartino, J., Palmer, S.E. (2012). Aesthetic issues in spatial composition: Effects of vertical position and perspective on framing single objects. Journal of Experimental Psychology: Human Perception and Performance, 38(4), 865-879.

Size Biases/Aesthetics

The preferences for size in a pictorial composition seem to emerge from the same mechanisms that gives rise to our preferences for objects in the vertical dimension.  In general, relatively small physical objects tend to be preferred when their images are small within a frame while relatively  large physical objects are preferred when their images are large within a frame.  Again, this can be considered an “ecological bias” as it appears to be driven by people preferring images in which the properties of the objects depicted within its frame mirror the ecological properties of the physical objects relative to the viewer.

“Akin to studies on canonical perspective, we provide evidence that existing object representations also have canonical visual sizes, which depend on the assumed size of the object in the world relative to a frame of space. Both perspective and visual size are spatial dimensions that are under the control of an active observer, in this sense canonical views connect physical objects to a viewer in an environment. In fact, if one combines canonical perspective at the canonical visual size, this object knowledge specifies the optimal place in 3D space from which to view an object.” -Konkle, Talia, and Aude Oliva. “Canonical visual size for real-world objects.” Journal of experimental psychology: human perception and performance 37.1 (2011): 23.

VSS 2010 Poster-Aesthetic Preferences in the Size of Images of Real-world Objects by Sarah Linsen, Mieke H.R. Leyssen, Jonathan Sammartino Gardner & Stephen E. Palmer

Fluency

Processing fluency is the ease with which information is processed. Perceptual fluency is the ease of processing stimuli based on manipulations to perceptual quality. Research in cognitive neuroscience and psychology has shown that processing fluency influences different kinds of judgments. For instance, perceptual fluency can contribute to the experience of familiarity when fluent processing is attributed to the past. Repeating the presentation of a stimulus, (a means by which to bring about the aforementioned priming effects) is one method for enhancing fluency.

Some research into aesthetics has given rise to a theory that attributes a good deal of aesthetic experience to processing fluency. The theory is known as the processing fluency theory of aesthetic pleasure.  The theory holds four basic assumptions:

1. Objects differ in the fluency with which they can be processed. Variables that facilitate fluent processing include objective features of stimuli, like goodness of form, symmetry, figure-ground contrast, perceptual priming, clarity, context, duration, repetition, well as experience with a stimulus, for example repeated exposure or prototypicality (the idea that prototypical and “average” forms are preferred over nonprototypical one.)
2.  Processing fluency is itself hedonically marked (that is, it possesses an inherent affective quality) and high fluency is subjectively experienced as positive.
3. In line with the “feelings-as-information” account, processing fluency feeds into judgments of aesthetic appreciation because people draw on their subjective experience in making evaluative judgments, unless the informational value of the experience is called into question.
4. The impact of fluency is moderated by expectations and attribution. On one hand, fluency has a particularly strong impact on affective experience if its source is unknown and fluent processing comes as a surprise. On the other hand, the fluency-based affective experience is discounted as a source of relevant information when the perceiver attributes the experience to an irrelevant source. This helps explain the inverted U-shaped function often found in research on the effect of complexity on preferences: Very complex patterns are not judged as beautiful because they are disfluent, and patterns are judged as more beautiful when they become less complex. When viewers perceive a simple pattern, they are often able to detect the source of fluency—the pattern’s simplicity—and do not use this experience of ease for judging the beauty of the pattern.

“Multiple theoretical notions converge on the assumption that high fluency is positively marked. The basic idea in all these notions is that high fluency says something about a positive state of affairs, either within the cognitive system or in the world (see Winkielman et al., 2003, for a more comprehensive treatment). Specifically, high fluency may elicit positive affect because it is associated with progress toward successful recognition of the stimulus, error-free processing, or the availability of appropriate knowledge structures to interpret the stimulus (Carver & Scheier, 1990; Derryberry & Tucker, 1994; Fernandez-Duque, Baird, & Posner, 2000; Schwarz, 1990; Simon, 1967; Ramachandran & Hirstein, 1999; Vallacher & Nowak, 1999). High fluency may also feel good because it signals that an external stimulus is familiar, and thus unlikely to be harmful (Zajonc, 1968, 1998).” -Reber, Rolf, Norbert Schwarz, and Piotr Winkielman. “Processing fluency and aesthetic pleasure: Is beauty in the perceiver’s processing experience?.” Personality and social psychology review 8.4 (2004): 364-382.

The idea that the amount of information that may be elicited from a sensory experience is an important determinant for the experience of “beauty” has a long history in the study of aesthetics (e.g., Arnheim,  1974; Gombrich,  1984). While I do not think that fluency is the sole wellspring of the aesthetic experience, I do believe that it may contribute to the majority of the experiences. For example, while symmetry is included in many studies of fluency, I find this consideration to be more effectively filed under a preference for stability (what I consider to be an ecological effect). Again, we may see some significant overlap between some of these ideas and how you choose to organize them for yourself should trump my map. What matters most here is how these considerations will ultimately serve your creative planning process.

Contrast

It is very important to remember that the visual system seems to be not all that interested (relatively) in gradual changes in the visual field, rather–our eyes tend to glide over homogenous regions and subtle changes in perceived luminance towards areas of increasing contrast or complexity in an effort to elicit information. It is at regions of discontinuity that we find the most robust amounts of visual information regarding our environment. “These abrupt changes are particularly important because they signify either a change in the reflectance of a surface (e.g., from one material to another), a change in the amount of light falling on it (e.g., due to a shadow), or a change in surface orientation relative to the light source (since most surfaces at different angles to the light source reflect different amounts of light into the eye). For these and other reasons, luminance edges are almost universally agreed to be important image-based features.” -Stephen  E. Palmer, Vision Science.

Research has also shown that recognition speed, a standard measure of fluency, is faster for stimuli high in figure-ground contrast (e.g., Checkosky & Whitlock, 1973).  This does not mean that  increases in contrast alone (nor increases in any independent attribute explored here) will result in a greater aesthetic experience. As shown by the origination of the consideration map, context is a governing factor in how these fluency attributes are processed by a viewer.

Constancy

Perceptual Constancy is the ability to perceive the unchanging properties of external objects rather than the more transient properties of their retinal images.  The brain has the unique ability to retain knowledge of constant and essential properties of an object and discard irrelevant dynamic properties. This applies not only to the ability to always see a banana as the color yellow but also the recognition of faces at varying angles.

While it would seem that perceptual constancy isn’t something that we can “add” to a picture, it is listed here as its consideration may help some to distil an object down to its most essential visual properties (which may be different from the way in which we actually “see” it). In fact, some may argue that the creation of many visual representations are modeled off of this primitive neural function. I touched on this idea in another paper titled Regarding Accuracy…,

“So if my goal is to emulate an accurate percept and I find length measurements of a distal stimulus has limited applicability, and length measurements of a proximal stimulus are easily prone to error, then shouldn’t I opt to chase an accurate visual simulacrum by just drawing or painting “what I see”?

No, not really.

Even though we are indeed attempting to generate an accurate recreation of a percept, attempting to draw or paint veridically from a percept without measurement will often lead to significant inaccuracies. Let me say that again—painting accurately, strictly from a percept without policing from proximal/distal stimulus measurement, will most often not result in an accurate recreation of that percept. Let me explain–if I observe object (A), my brain will generate a reflexive response percept (A1). Therefore if I paint true to percept (A1), a subsequent viewing may elicit percept (A2) (or (A1(artist)+1(viewer)) as their reflexive response to my simulacrum is also not veridical. While this is not “bad” in itself—the more distant (A1) is from (A), the less realistic the resulting effort will appear.”

Skillfully distilling an object down to visual essentials may allow room for the “visual contributions” of a viewer.

Abstraction

A consideration of abstraction here may seem quite similar to our efforts regarding an accounting for constancy—and indeed it is.  However, abstraction is the manner (e.g., hierarchical coordination) in which we choose to reduce complexity to a form that may be more efficiently processed.  So while can look at the consideration of constancy as a tool to reveal WHICH attributes remain “constant”, abstraction is the means of simplification that may differentiate these attributes from unessential ones.

It is worth noting here that Professor Semir Zeki, one of the founders of the emerging field of neuroaesthetics, proposes that the visual brain holds two supreme laws: constancy and abstraction.

The next several considerations are closely connected in many ways:

Perceptual Problem-Solving

A consideration of problem-solving here may seem redundant as it some may see it as inherent to the concept of fluency already (e.g. the problem of how to best acquire and/or process information). However, the consideration of problem-solving in this context comes from another pioneer of neuroaesthetics, neuroscientist VS Ramachandran. Among his eight laws of artistic experience, he includes problem-solving (being tied to the detection of contrast and grouping) as the idea that a visual “discovery” after a struggle is more pleasing than one which is instantaneously obvious. The mechanism ensures that the struggle is reinforcing so that the viewer continues to look until the discovery. From a survival point of view, this may be important for the continued search for predators. Ramachandran suggests for the same reason that a model whose hips and breasts are about to be revealed is more provocative than one who is already completely naked. A meaning that is implied is more alluring than one that is explicit.

This is a consideration that I explore quite often.  I make a significant effort with most of my works to “layer” information so that extended investigations/explorations will hold the possibility of new discoveries after more cursory elements are familiar.

I would also like to make a note here that the effects of perceptual problem-solving may actually benefit works (in regards to viewer attention) that contain significant deviations from familiar percepts (e.g., drawing/painting errors, heavy stylization, etc.). Some studies into the manner in which we engage with pictures have shown that we will often return to “problem areas” in a complex stimulus, over and over in an attempt to effectively find a resolve to the issue(s).

Visual Metaphor – Ramachandran defines a metaphor as a mental tunnel between two concepts that appear grossly dissimilar on the surface, but instead share a deeper connection. Similar to the effects of perceptual problem solving, grasping an analogy is rewarding. It enables the viewer to highlight crucial aspects that the two objects share. Although it is uncertain whether the reason for this mechanism is for effective communication or purely cognitive, the discovery of similarities between superficially dissimilar events leads to activation of the limbic system to create a rewarding process.

Perceptual Grouping

Perceptual grouping refers to the process by which the various elements in an image are perceived as “going together” in the same perceptual unit of experience.

Of perceptual grouping, Ramachandran states that the source of the pleasure may have come about because of the evolutionary necessity to give organisms an incentive to uncover objects, such as predators, from noisy environments. For example, when viewing ink blots, the visual system segments the scene to defeat camouflage and link a subset of splotches together. This may be accomplished most effectively if limbic reinforcement is fed back to early vision at every stage of visual processing leading up to the discovery of the object. The key idea is that due to the limited attentional resources, constant feedback facilitates processing of features at earlier stages due to the discovery of a clue which produces limbic activation to draw one’s attention to important features.Though not spontaneous, this reinforcement is the source of the pleasant sensation. The discovery of the object itself results in a pleasant ‘aha’ revelation causing the organism to hold onto the image.

Novelty

While it seems that most artists are always striving to create something novel, an extremely novel representation may lead to issues in recognition.  The challenge for an artist seeking a novel representation is to balance recognition with the interest from a problem-solving effort.  Making something too distant from well-understood conventions of visual communication may result in your message going unheard.

At this point we should take a look at some concepts of recognition including pattern and likeness.

Recogntion – is a term that describes a cognitive process that matches information from a stimulus with information retrieved from memory.

There are several fascinating hypothesis regarding our mechanisms for recognition, but the ones that are most applicable here are recognition of pattern or likeness. While pattern recognition may be defined in most contexts as mere categorization, I am choosing to define it more specifically (for our purposes) as our ability to achieve recognition through visual repetition or grouping that occurs with discernible regularity. This might allow us to more fruitfully explore novel representations as the recognition may be augmented by a familiarity inherent to the interval/relationships rather than the actual occurrence at the interval. Recognition by likeness would in turn be the manner of matching information from a stimulus with an existing categorical classification.

As with the other aspects of aesthetic sensation describes here, recognition often gives a pleasing experience. In this context, I assume that it is clear how recognition is connected to constancy, perceptual problem-solving, and grouping. Additional considerations of fluency (perspective and orientation) are also closely connected to recognition.

Orientation/Canonical Perspective

Orientation of a representation may have much to do with how well it may be perceptually processed. This consideration is often regarded as “canonical perspective”.  Studies into recognition have shown systematic variations in naming latencies suggesting that certain manners of orientation affect perceptual fluency.  While there are a few ideas to explain these canonical perspective effects–the two most obvious are:

Frequency Hypothesis: Our canonical perspectives are determined by an “ecological bias” in that the preferred orientation is that view which aligns with the orientation most frequently encountered in the physical world.

Maximal Information Hypothesis: Our canonical perspectives are determined by the perspective that offers the greatest amount of information about the object and its potential function.

In his book Vision Science, Stephen E. Palmer writes of these two hypotheses, “It is likely that both hypotheses contain some measure of truth and that the perspective effects Palmer et al. reported depend jointly on both. Canonical views appear to provide the perceiver with what might be called the most diagnostic information about the object: the information that best discriminates it from other objects, given what the perceiver knows, derived from the views from which it is most often seen.”

I would also like to take a moment here to address a more “semantic” issue in regards to orientation preferences in a pictorial context. Some studies have indicated very clearly that, beyond some minimum distance, there exists a preference for related objects to be relatively close together, but unrelated objects to be relatively far apart. (Leyssen, Mieke HR, et al.2012).  Additionally, there seems to be general non-preference for occlusion.  Occlusion is the condition in which light reflected from a farther object is blocked from reaching the viewer’s eye by an opaque object between the viewer and the occluded object. While I do not think that this would be the case in all contexts, with a basic framework of how we garner pleasure from processing fluency, you can see how some contexts might make this so.

Viewpoint

Another of VS Ramachandran’s eight laws of the artistic experience is called The Generic Viewpoint. The visual system dislikes interpretations which rely on a unique vantage point. Rather it accepts the visual interpretation for which there is an infinite set of viewpoints that could produce the class of retinal images. For example, in a landscape image, it will interpret an object in the foreground as obscuring an object in the background, rather than assuming that the background figure has a piece missing. In theory, if an artist is trying to please the eye, they should avoid such coincidences. However, in certain applications, the violation of this principle can also produce a pleasing effect.

Stability

In many ways, stability may be very closely connected to orientation. However, I feel that the preferences for balance and symmetry may emerge from survival instincts regarding shelter and reproduction (e.g., preference for a shelter that is not likely to fall or give way; resources likely to continue or last; a sign of health in a potential mate, etc.) instead of preferences based on processing fluency.

Balance/Symmetry

According to art theory, pictorial balance is a sense of equilibrium achieved through implied weight, attention, or attraction, created by manipulating the visual elements in an artwork. The balancing of elements is thought to be similar to balancing mechanical weights in a framework of symmetry axes. There are several different “types” of pictorial balance including symmetrical (even distribution of elements relative to a central axis), asymmetrical (irregular or uneven element arrangement), radial (elements arranged radially around a central point), ambiguous/neutral (equilibrium in spite of characteristically unclear element relationships or seeming randomness).

Many properties can contribute to the “visual weight” of an object. These attributes can include, “size (Berlyne 1966, 1971, 1974; Pierce 1894; Puffer 1903), color (Arnheim 1974; Bullough 1907; Pinkerton and Humphrey 1974), and perhaps coarse texture, contrast, and interest.”-Gershoni, Sharon, and Shaul Hochstein, “Measuring pictorial balance perception at first glance using Japanese calligraphy.” i-Perception 2.6 (2011): 508-527.

As with most other aspects of pictorial composition, our sense of balance is born from our own biology.  Particular preferences can be traced back to specific biological mechanisms. For example, “Paintings and drawings are perceived differently when viewed in mirror image; left and right have different roles in expressing action, motion, or power (Chatterjee 2002), and the left half of visual space may attract more attention, due to right parietal lobe specialization in attention and emotion (McManus 2002). Similarly, using the ecological view that in natural scenes visual field bottom is generally more crowded, it was suggested that weight at the top should be perceived as “heavier” than at the bottom (Arnheim 1974, 1981).”-Gershoni, Sharon, and Shaul Hochstein. “Measuring pictorial balance perception at first glance using Japanese calligraphy.” i-Perception 2.6 (2011): 508-527.

Here are some of the findings from the Gershoni study above. They offers a wonderful insight into understanding “balance”:

“…We review here the most salient elements that seem to drive balance perception, leaving detailed study of these trends to further systematic study:

Horizontal and vertical elements. The most-balanced sets are composed mainly of horizontal and vertical elements. In the less-balanced stimulus sets the main feature is a lack of straight lines. This is consistent with the aesthetics oblique effect; for example, observers show aesthetic preference for Mondrian paintings oriented with vertical and horizontal elements over rotated versions with oblique elements (Latto and Russel-Duff 2002; Latto et al 2000; Plumhoff and Schirillo 2009).

Vertical mirror symmetry. In the more balanced images vertical symmetry is either maintained or, with grouping of a number of non-vertical elements, even enhanced. With 90° rotation there is a switch from vertical symmetry to horizontal symmetry. As a result, vertical symmetry may be violated and the image is perceived as less balanced. This effect is exacerbated for ±45° rotations, when the symmetry is around the diagonals. These results are consistent with previous studies that found vertical mirror symmetry salience compared with horizontal or centric mirror symmetry in a variety of object perception tasks and suggested that vertical mirror symmetry is used as a cue for figure–ground segregation and element grouping in a display of Gabor elements (Machilsen et al 2009; Wenderoth 1994, 1995). We now suggest that vertical symmetry is also a critical cue for perceived balance.

Imprecision of verticality and horizontality. According to Japanese calligraphy tradition, all seemingly horizontal lines are in fact either slanted or slightly arched. Yet they are satisfactorily perceived as horizontal. For example, in the very top set of Figure 10 the horizontal lines are curved mostly above or below the horizontal axis, yet are perceived as resting on the horizontal axis. This is in line with Arnheim’s (1974) observation that visual experience cannot be described in terms of precise property measurement units. For example, when people see a 93° angle they perceive “an inadequate right angle”. Likewise, almost perfectly parallel lines are as likely to be perceived as parallel or as not parallel (Kukkonen et al. 1996). Quasi-invariant properties such as near parallelism are influential in object recognition over novel viewpoints and rotations.”

While a sense of equilibrium may appeal to our preference for stability, an “unbalanced” composition may elicit a sense of tension and unease. Keep this in mind when you are considering how to incorporate “balance” into your compositions.

Color

There are vast resources available today on the topic of color preferences and color harmonies. I do not wish to spend any time here entertaining ideas of how “yellow makes you feel this way” and “blue makes you feel that”, or what color do people “like most”, rather I would like to address two color considerations that I contemplate during composition efforts: Color Grouping preferences and EVT (Ecological Valence Theory). If you are interested in studies about general color preference, I would direct you to: Palmer, S. E., & Schloss, K. B. (In press). Human color preference. In N. Moroney (Ed.), Encyclopedia of Color Science and Technology. Springer. If you would like to learn more about general object color preferences: Schloss, K. B., Strauss, E. D. & Palmer, S. E. (2012). Object color preferences. Color Research & Applications.

Color Grouping

As far as general color combination preferences go, studies have shown that there is a general preference for harmonious combinations of the same (or similar) hues that differ in lightness.  Although it is not immediately obvious why this might be the case from an ecological viewpoint, some suggested that it might stem from ecological color statistics in natural images corresponding to different areas of the same ecological object . A red sweatshirt, for example, would be darker red where it was in shadow and lighter red where it was brightly illuminated. Such findings for spatial preferences based on similar attributes are reminiscent of preferences for semantically related objects to be close together and unrelated objects far apart.  (Leyssen, Linsen, Sammartino & Palmer, 2012).

VSS 2012 Poster-Effects of grouping on preference for color triplets by Christopher Lau, Karen B. Schloss & Stephen E. Palmer

EVT (Ecological Valence Theory)

This idea always made great sense to me. The EVT states that color preferences arise from people’s average affective responses to color-associated objects. Empirical testing shows very strong support for this theory.  For example, “People like colors strongly associated with objects they like (e.g., blues with clear skies and clean water) and dislike colors strongly associated with objects they dislike (e.g., browns with feces and rotten food). Relative to alternative theories, the ecological valence theory both fits the data better (even with fewer free parameters) and provides a more plausible, comprehensive causal explanation of color preferences.” -Palmer, Stephen E., and Karen B. Schloss. “An ecological valence theory of human color preference.” Proceedings of the National Academy of Sciences 107.19 (2010): 8877-8882.

And there you have it.  A full walk-through of my considerations for pictorial composition along with the scientific support to demonstrate how and why it works. There is much more that can be added here but again, this is only meant to be a starting point. Remember that this map is not a unidirectional flowchart—but rather, like some well-illustrated concepts of visual processing, is a framework of bottom-up and top-down considerations that outlines a highly dynamic process.

I would like to close by stating that using the popular heuristics that we discussed in the earlier installments (golden ratio, rule-of-thirds, dynamic symmetry, etc.) is not necessarily a “bad” practice.  They will not necessarily make your artwork “bad”.  They are just a means by which to organize elements in a pictorial space. The problem is that they hold no better utility than random chance.  Their apparent “success” is only seen when they happen to coincide with one of the above preferences by chance. For example, if you placed a figure near the left intersections of the rule-of-thirds armature, and the figure is facing inward, it may look great. Again, this is not due to placement at a heuristic armature intersection but is rather due to the fact that figure is appealing to an inward bias where spatial preferences within a frame are concerned. I hope at this point you can understand this fact.

Remember that just because you come across some food when you were waving your arm does not mean that the movement of your arm caused the food to appear.  😉

Happy Painting.

 

RESOURCES

Among the many resources that I have used for this entire primer, two of the most most valuable have been the websites of Dr. Dale Purves (purveslab.net) and the website of Dr. Stephen E. Palmer (socrates.berkeley.edu).  From visual perception and its neurobiological underpinnings to the study of the aesthetics of color and spatial arrangement—I could not imagine two more valuable online resources.

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Zeki, Semir. (2008). Splendours and Miseries of the Brain, Wiley Blackwell

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Zeki, Semir (2008): Splendors and Miseries of the Brain. Love, Creativity, and the Quest for Human Happiness. Oxford: Blackwell.

Additional sites:

Dr. Beau Lotto’s LottoLab (http://www.labofmisfits.com/)

Saul McLeod’s Simply Psychology (http://www.simplypsychology.org/)