Beauty, pleasure, and emotions
As mentioned in earlier chapters, art is a human-unique, socially anchored communicative system for concepts formed in the mind. Messages are relayed from artist to viewer, and a mechanism for attraction to the message is beauty. Beauty is thus viewed here as a tool to attract attention to what is being communicated in an art work (Zaidel, 2015b). Art and beauty are intertwined in the sense that the aesthetic reaction attracts our attention to the messages and signals in the art. This notion is labled attention-attraction by D. W. Zaidel (2015b). The idea was developed against a biological background of mate selection strategies, in which males of many species attract the attention of potential female mates to their physical qualities via ritualistic courtship displays (discussed in Chapter 10). Choice by a female of the fittest male based on a physical display maximizes the survival chance of the offspring, which assumes the further survival of the species as a whole. Thus, courtship displays are a platform where survival-type physically seen qualities are exhibited. We do not know whether or not aesthetic reactions, to any source, are unique to humans; we do not know whether animals possess beauty reactions. It is nevertheless helpful to seek the roots of our aesthetic sense in biology; this topic is discussed in subsequent sections.
Aesthetic taste could sometimes seem purely subjective and to lack neuroanatomical basis but, in fact, it emanates from neural activity (see discussion in subsequent sections below). There are several directions of inquiry into this question. What are the cytoarchitectural and excitatory principles on which aesthetic responses might rest? What role do aesthetic standards play in the neural response? What is the biological purpose of aesthetic taste in the first place? Answers have been found to some of these. The aesthetics topic has been debated in evolutionary circles (Aiken, 1998; G. Miller, 2000), in psychology (Leder & Nadal, 2014), and in neuroscience, where it is now known as neuroaesthetics (Pearce et al., 2015).
Humans react to perceived visual beauty regardless of its format in nature or on canvas. The former is three-dimensional while the latter is often two-dimensional (paintings, drawings, etchings). The latter does not have to faithfully represent reality in order to elicit beauty-related reactions. We respond to the beauty we perceive in paintings by the Cubists, modern abstract painters, or Surrealists as well as to classic Chinese and Japanese art where there is little attempt to depict three-dimensional space. So beauty reactions are independent of the degree to which reality is represented. It is quite remarkable that photographic close-ups of a hand or a glass can elicit beauty reactions and at the same time so do wide-angle vistas such as what we see from mountain tops or high-rises, when driving in the desert, or when sitting on a beach. Visual angle is not crucial here. And there are specialty scenes in films that are relevant, described by a leading film critic, Roger Ebert (2002):
Three films [the Apu Trilogy] were photographed by Subrata Mitra, a still photographer whom Ray [the director] was convinced could do the job. Starting from scratch, at first with a borrowed 16mm camera, Mitra achieves effects of extraordinary beauty: forest paths, river vistas, the gathering clouds of the monsoon, water bugs skimming lightly over the surface of a pond.
(Ebert, 2002, p. 46)
It seems that words alone cannot convey the range of visual events that give rise to the beauty-related responses that Ebert is describing. These events are varied and widespread in human existence. Exploring the responses empirically has seen a surge in several laboratories throughout the world. Is the beauty of a face the same as the beauty of a painting, or of a sunset over the Pacific Ocean viewed from a cliff in southern California? These are some of the challenging questions researchers are attempting to tackle. Furthermore, beauty’s anchor in biology makes untangling it different from untangling other basic biological reactions because, as stated above, as far as we know animals do not experience beauty. The empirical work that has been done shows that aesthetic judgments have a neuroanatomical underpinning, and this is explored below in the section on neuroaesthetics.
Beauty itself could be viewed as an emergent property in the brain of the viewer of the art (Zaidel, 2015b). That is, the beauty aspect of a work of art is something that the observer who did not create the art sees. The artist’s intentions do not necessarily “put” the beauty in the art as a distinct entity. The beauty reaction emerging in the viewer reflects the working of the mind in the brain of the viewer. Thus, the neuroanatomical underpinning of beauty applies to the viewer’s interpretation but not to the building blocks in the creating of the work, perhaps in much the same way that consciousness is seen as the emergent property of neural activity (Sperry, 1980). Picasso commented that art is not infused with aesthetics for its own sake but rather as a way to represent what is on the mind: “Painting isn’t an aesthetic operation; it’s a form of magic designed as a mediator between this strange, hostile world and us, a way of seizing the power by giving form to our terrors as well as our desires” (quoted in Gilot & Lake, 1964, p. 266).
Neurological cases of non-artists displaying changes in artistic taste after brain surgery or injury are remarkably few. Sellal and associates described a right-handed man with circumcised surgical excision who had suffered from epilepsy since age 18 years (Sellal et al., 2003). The seizures were attributed to a tumor identified as a ganglioglioma situated in the left third temporal gyrus (T3). At age 21 he underwent left temporal lobectomy to alleviate drug-resistant epilepsy. The surgery consisted of resection of the anterior temporal pole as well as of other temporal lobe regions (T2, T3, T4, and T5). The hippocampus, the parahippocampal gyrus, and the amygdala were not removed. The seizures disappeared following surgery. Neuropsychological tests prior to surgery revealed worse verbal than visual memory and presence of a mild anomia. Following surgery, the tests indicated that verbal memory was at normal level, but the mild anomia remained unchanged. Both verbal and performance IQ (intelligence quotient) increased by a few points. Auditory tests showed deficits in pitch and tone discrimination without there being hearing loss. Here is the interesting outcome to our discussion: he reported in the year following surgery that he had developed new musical, visual art, and literary preferences.
Formerly a “fan” of rock music, he found that the music he used to listen to before the operation sounded “too hard, too fast, and too violent.” He now had a preference for Celtic or Corsican polyphonic singing and was unable to listen even to one of his rock songs. In literature he completely lost his taste for science fiction books and now preferred novels, e.g., the novels from Buzzati [an Italian author]. In paintings, he showed increasing interest in realistic works, in which he liked the fine detail he was formerly unable to appreciate.
(Sellal et al., 2003, p. 449)
In contrast to all of this artistic-related preference, the patient’s food, dress, and face preferences remained unaltered, and personality changes were not noted (based on informal observations as well as on a standardized personality test). “The patient was surprised by his taste changes, did not find that they were the mere consequence of maturation, and complained about them: he now had difficulty staying with his old friends, since he could no longer share his musical preferences and hence his topics of discussion” (Sellal et al., 2003, p. 449).
An exceptionally brief report about a change of musical taste in a dementia patient was published in 2001: “A man exhibited typical features of semantic dementia, with onset at age 52. At age 55, he became infatuated with polka music. He would sit in his car in the garage and listen to polka on the radio or on cassettes, often for as long as 12 to 18 hours” (Boeve & Geda, 2001, p. 1485). The obsessive interest in polka was a new development, presumably not observed prior to illness onset, but developing an obsession is not unusual in dementia patients. In this patient, magnetic resonance imaging (MRI) scans taken at ages 53 and 55 years indicated progressive amygdala and temporal cortex atrophy, bilaterally. Here we do have involvement of a limbic structure. What is not clear, because of the brief nature of the case description, is whether what was new was the obsession itself or the interest in polka. Preference and taste for art could have “obsessive” qualities and the infatuation with polka is an example of this.
Two neurological cases diagnosed with frontotemporal dementia (FTD) had alterations in musical taste (Geroldi et al., 2000). In both there was bilateral atrophy of the frontal and temporal lobes as well as enlargement of the lateral ventricles, particularly of the frontal and temporal horns. In case one, a 68-year-old lawyer, there was slightly greater right-sided atrophy while in case two, a 73-year-old housewife, the atrophy was symmetrical. In case one,
the pre-morbid musical preferences had been directed to classical music, and he used to define pop music as “mere noise.” About 2 years after his diagnosis, he started to listen at full volume to a popular Italian pop music band—“883.” During the following 2 years, apathy worsened, spontaneous speech production was reduced, and the patient lost emotional contact with his family. However, he kept listening to 883 for many hours daily, actively looking for tapes, and using the recorder. Three years after onset, the patient developed motor neuron disease. He died 4 years after initial diagnosis.
(Geroldi et al., 2000, p. 1935)
In case two, prior to disease onset the patient did not have a particular interest or enjoyment in music. About a year after disease onset this changed: she began to show excessive interest in pop music, the same music that interested her 11-year-old granddaughter. She now listened to Italian pop bands as well as pop singers, noting their beautiful voices and pleasant rhythms. Again, the obsessive nature of the interest could be more important in explaining the symptoms than the particular relationship to art.
Additional cases of FTD with obsessive–compulsive need to listen to music have been reported (Hailstone, Omar, & Warren, 2009). Indeed, de novo obsessive–compulsive interest in music is now labeled musicophilia. Neurological patients with non-dementing conditions such as epilepsy have developed musicophilia following introduction of a new drug or new brain stimulation, thereby showing that aesthetic preference or taste are not at the bottom of the disorder (Fletcher, Downey, Witoonpanich, & Warren, 2013).
The brain alterations associated with the dementing process are clearly implicated in these (seemingly) aesthetic preference changes, especially alterations in inhibition–disinhibition disregulation. The disease process not only includes death of neurons but also disrupts connectivity among and between neurons. It is thus not obvious at all that the changes are related to aesthetic preference; they could reflect a change in interest due to an obsessive–compulsive process brought about by the disregulation. Further, the post-damage alterations in pre-damage preferences can occur in domains wholly separate from art. Examples include dramatic alteration in emotional attachment following right temporal lobectomy (Lipson, Sacks, & Devinsky, 2003); alterations in food preference following head trauma (Fugii, Fujita, Hiraatsu, & Miyamoto, 1998); and drug-induced (side effect) alterations in sexuality, tongue taste, and smell in patients with dementia, Parkinson’s, and other etiologies (Naik, Shetty, & Maben, 2010).
Actually, researchers have found that aesthetic responses are stable in dementia, regardless of the memory or cognitive deficits experienced by these patients (Halpern, 2013; Halpern, Ly, Elkin-Frankston, & O’Connor, 2008; Silveri et al., 2015). The obsessive–compulsive activity, then, reflects a tangential relationship to aesthetics, a side effect of sorts.
Since the publication of the first edition of this book there has been an upsurge in research into brain activity in aesthetic reactions to art. The surge has richly expanded the field of neuroaesthetics (reviewed in detail in Brown, Xiaoqing, Tisdelle, Eickhoff, & Liotti, 2011; Jacobsen, 2013; Nadal, 2013; Pearce et al., 2015; Vartanian & Skov, 2014). In addition, empirical aesthetics has elaborated on the aesthetic process in the mind of the viewer (Leder & Nadal, 2014). The brain and aesthetics studies used a wide range of techniques, including functional magnetic resonance imaging (fMRI), event-related potentials (ERP), electroencephalography (EEG), magnetoencephalography (MEG), and transcranial magnetic stimulation (TMS). Importantly, the studies were conducted with healthy subjects with no known brain damage. The stimuli, experimental design, and procedures have not been identical across studies. However, the neural landscape that emerged indicates within and among studies that aesthetic reactions recruit multiple neural regions and pathways connecting sensory and association cortexes whose functional properties include perception, emotion, and cognition. Aesthetics in the context of art, then, has been shown to have a solid neural basis.
Currently, when all studies are considered together, the neural landscape reveals that (1) beauty responses do not represent a single, unitary event in the brain specializing in “beautiful” or “ugly,” or even in a continuum between these two poles. Rather, researchers have now distinguished between beauty experience responses and beauty judgment responses (Ishizu & Zeki, 2013). (2) Multiple neural areas are active and they are distributed across both hemispheres and within each hemisphere; in some studies hemispheric regional activation is unilateral while in others it is bilateral. (3) Beauty responses involve cortical areas controlling cognitive functions such as semantic knowledge and decision-making, as well as goal-directed behavior, emotional reactions, memory, and motor output. (4) They also involve primary sensory areas: in the case of visual art, the occipital lobes (areas where input from the eyes is first processed in the cortex) are active, and in the case of music the anterior temporal lobes (where signals from the ears are processed in the cortex) are active. (5) Functionally separate regions of the prefrontal cortex (medial orbitofrontal, anterior medial, dorsolateral, and ventrolateral) are maximally engaged. (6) Limbic system regions involved in emotions, such as the anterior and posterior cingulate gyri, the insula, and the amygdala, are also active. (7) The junction of the parietal and temporal lobes, poles of the temporal lobes, and precuneus in the parietal lobes are all regions that show activation. (8) Motor systems in the basal ganglia such as the globus pallidus and putamen, and (9) subcortical structures such as the nucleus accumbens and cerebellum, show increased activity. Clearly, across all studies and their differing methodologies, there is wide and distributed brain activity reflecting the neural bases for reactions to art-related aesthetics (Cela-Conde, Agnati, Huston, Mora, & Nadal, 2011).
Of great interest, in particular, are studies that involve passive viewing of visual art stimuli—that is, no explicit instruction to judge, decide, evaluate, or rate the works. In two such fMRI studies (Harvey, Denfield, & Montague, 2010; Kirk, Harvey, & Montague, 2011), specific areas within the frontal lobes were maximally active when subjects viewed paintings. One area was the ventromedial prefrontal cortex (VMPFC; Harvey et al., 2010), while in a separate experiment the dorsolateral prefrontal cortex, adjacent to the VMPFC, was preferentially active (Kirk et al., 2011). The fact that the greatest activation was seen in the prefrontal cortex is significant because of that area’s evolutionary expansion in humans.
The medial orbitofrontal (mOFC) area is another example of an important prefrontal cortex area that shows activity in aesthetic responses (Di Dio, Macaluso, & Rizzolatti, 2007; Ishizu & Zeki, 2011; Vartanian & Goel, 2004). Significantly, in the Ishizu and Zeki study (2011) the mOFC region (which partly overlaps with Brodmann Area 10) was found to be preferentially active in response to both visual and musical art, and the reported intensity of the subjective reactions was proportional to the amount of activation: the more intense, the greater the activation. In addition, the authors zero in on a specific neural zone within the mOFC as being the most consistently active in their study and call it A1.
There is significance to the activation of the prefrontal regions in aesthetic reactions. The human phylogenetic and evolutionary trajectory of the prefrontal lobes consists of expansion in certain regions relative to the rest of the brain and relative to non-human primates. The frontal tip (pole) is particularly well developed in humans (Brodmann Area 10) and has shown the largest size growth compared to non-human primates (Kaas, 2013; Semendeferi, Armstrong, Schleicher, Zilles, & Van Hoesen, 2001). Currently, since there is no evidence that animals experience aesthetic reactions, it is reasonable to speculate that a human-unique system such as art elicits aesthetic responses in a human-unique brain region.
Reactions to art do not always elicit feelings of pleasure. However, many researchers explain the activation of the mOFC (described above) in terms of its connectivity to brain regions associated with the so-called “reward system” and its relationship to presumed pleasure; the reward system is also known as the mesolimbic reward system. The implication is that aesthetic responses have a “reward” value of sorts and that aesthetic responses are produced in the brain for pleasure.
The “pleasure center” in the brain is part of a neuronal network known as the reward system. The hypothalamus is strongly associated with the center through its extensive connections to the septum, a structure located just in front of it. James Olds and Peter Milner accidentally discovered the pleasure center in 1954 while searching for a completely different brain mechanism, one that is associated with learning (Olds & Milner, 1954; see also Kringelbach & Berridge, 2012). When an electrode was accidentally inserted into a rat’s septal area and an electric current stimulated the area, the rat continued to press a lever non-stop in order to receive this stimulation (aversive as it was), all the while going without food or drink for hours. Rats pressed the lever to get more and more of the electrical stimulation even when they were near starvation. This was interpreted at the time to mean that the rat obtained pleasure. Later experiments replicated the response in monkeys. In humans, a medical doctor had the idea that this procedure of self-stimulation through brain-implanted electrodes could bring relief from intractable pain (Milner, 1991). However, electrical stimulations of the “pleasure center in humans” has never been reported to lead to sensations of pleasure. If anything the subjects desired more stimulation for its own sake (Kringelbach & Berridge, 2012). Since the discovery by Olds and Milner (1954), scientists have worked out which other regions are connected to this hypothalamic region and they have concluded that reward is not the best label for what this pathway mediates (Neill, Fenton, & Justice, 2002; Schultz, 2000).
Although ventral tegmental neurons have traditionally been labeled “reward” neurons and mesolimbic DA [dopamine] referred to as the “reward” system, this vague generalization is not matched by the specific findings that have been observed. The scientific meaning of the term “reward” is unclear, and its relation to concepts such as reinforcement and motivation is often ill defined.
(Salamone & Correa, 2012, p. 470)
The reward circuit consists of the medial forebrain bundle (MFB), which goes through the hypothalamus, along with the mesolimbic dopamine system, which synapses on the nucleus accumbens (NA). Stimulation of the MFB releases the neurotransmitter dopamine from the NA. Importantly, the NA sends numerous axons to dopaminergic-sensitive neurons in the frontal and temporal lobes (including the hippocampus). The NA also receives projections from the cortex, amygdala, and hippocampus, and this implies that secretion of dopamine by the NA occurs with information arriving from regions other than the MFB. Prefrontal lobe neurons are particularly sensitive through their specialized receptors to the action of dopamine. Numerous studies in animals have found that NA dopamine is important in activating behavior, exerting effort, transferring conditioned learning, allowing flexibility in behavioral approach, expanding and regulating energy, and utilizing learning involving rewards (important to animals; Berridge & Kringelbach, 2013; Gardner, 2011; Kringelbach & Berridge, 2012; Salimpoor, Benovoy, Larcher, Dagher, & Zatorre, 2011). The generalization from animal experiments to cognitive (Schultz, 2004) or aesthetic responses to art works in humans needs to be questioned; currently, the generalization seems an intellectual leap.
Although dopamine was originally associated with triggering the sensation of pleasure, many studies investigating the effects of dopamine in drug addiction and dependence have not found a link between dopamine (facilitated in the brain when drugs are consumed), reward, and pleasure (Salamone & Correa, 2012). The association of dopamine with the NA, the MFB, and the prefrontal cortex has led to erroneous conclusions that activation of the mOFC in aesthetic-related studies is evidence for pleasure obtained from aesthetic reactions.
Two important leading scholars and researchers in the field, John Salamone and Merce Correa, put it thus:
Furthermore, despite an enormous literature linking mesolimbic DA to aspects of aversive motivation and learning, a literature which goes back several decades …, the established tendency has been to emphasize dopaminergic involvement in reward, pleasure, addiction and reward-related learning, with less consideration of the involvement of mesolimbic DA in aversive processes.
(Salamone & Correa, 2012, p. 471)
Moreover, with regards to pleasure, it is difficult to ascertain whether relief from pain is the same as sexual pleasure, or the pleasure that comes from viewing art works, or pleasure from successful accomplishment, reading cartoons, watching film tracks of the Marx brothers or Eddie Murphy, or relaxing on vacation. The supposed pleasure that the rats experienced when Olds and Milner (1954) stimulated their brains could have just triggered a sensation of relaxation, or some other sensation that leading researchers into this “reward–pleasure” system propose (Munar et al., 2012). In any case, the reward system and pleasure-related responses in the context of aesthetics constitute a “nice story,” not necessarily one based on compelling scientific facts. Dopamine is not just for pleasure or “reward.” It is more parsimonious to conclude that the dopamine system has been fashioned by evolution for hundreds of millions of years to react to physiological and visceral events, not to brief and ephemeral beauty reactions to art.
Using the method of MEG, Cela-Conde and colleagues (2004) measured brain activity in eight female subjects in an aesthetic judgment task. While viewing a wide range of colored pictures, subjects were asked to indicate whether a picture was beautiful or not. Half the subjects responded by raising a finger if they thought the stimulus was beautiful and the other half responded with a raised finger if the picture was not beautiful. The pictures were carefully selected not to include close-up views of faces, and they represented art works of many genres (classical, abstract, Impressionist, and Postimpressionist) and subjects (photographed scenery, landscapes, and objects). In all, there were 320 pictures, which were carefully controlled for complexity, color range, luminosity, and light reflection. The results of the MEG recordings showed significant preferential activation in the left prefrontal dorsolateral area when stimuli were judged beautiful, regardless of whether or not the material consisted of art works. As would be expected, there was simultaneous activation in the visual cortex. On the whole, beautiful stimuli triggered more cerebral activation than non-beautiful stimuli. Moreover, more left hemisphere sites were active than right hemisphere sites regardless of the nature of the stimulus (beautiful or not). This study used the most extensive range of pictorial stimuli, and the most controlled stimulus selection procedures, applied to date. No breakdown with regards to art movement style is provided, but with time we could learn about additional cortical correlates of aesthetic judgment of the different movements. It could, however, turn out that aesthetic judgment is uniform across all art genres. For now, it is clear that there is no distinction between painted art works and photographed nature, and that the left hemisphere is more active in aesthetic judgment than the right (although the reasons why this should be so are subtle).
With fMRI, Kawabata and Zeki (2004) studied brain activation of subjects who viewed paintings representing a variety of categories (faces, landscapes, still lifes, or abstract). Unlike the MEG study above where the subjects did not view the stimuli prior to the brain recordings, the subjects here saw the paintings between three and six days prior to the brain scans. There were 10 subjects (five females, five males). In the fMRI procedure, 192 paintings were exposed twice (altogether 384 presentations) and the task was to indicate by pressing a button whether each stimulus painting was beautiful, ugly, or neutral. The authors found activation in several cortical areas including the visual cortex, motor regions, anterior cingulate, and orbitofrontal regions, largely for beautiful works. As in the MEG study, they also found that no separate specific area was engaged when stimuli were perceived to be ugly. However, because of the multiple stimulus presentations to the subjects, interpretation of the results is muddied by the mere exposure effect and familiarity (Kunst-Wilson & Zajonc, 1980). These effects alter responses in that they increase the likelihood of positive preference. Moreover, the portraits elicited strong activation in the fusiform gyrus, as would be expected if photographs of faces were used. Measurement of the aesthetics of portraits as paintings is complicated by their very depiction of a human face. Thus, it is difficult to interpret the reactions as distinct from aesthetic judgments.
In another important fMRI study examining aesthetics in paintings, the investigators showed their subjects abstract and realistic paintings and measured brain activation while aesthetic judgments were provided (Vartanian & Goel, 2004). There were 12 subjects (10 females, two males); only 40 stimulus paintings were administered. The original 40 stimulus paintings were altered in three different ways so that in the end subjects viewed 120 presentations. The task for the subjects was to rate each stimulus presentation on a 0–4 scale, where 0 represented very low preference while 4 represented very high preference. In general, subjects preferred representation over abstract paintings. With regards to brain activation, the significant results showed increased activation in the left cingulate sulcus, particularly to paintings with the highest ratings. There was a similar association in the occipital gyrus (bilaterally). The latter is not surprising, given visual stimulation in the very viewing of the paintings. What is remarkable, and in agreement with the MEG study, is the selective activation of the left hemisphere for beautiful ratings. Further, there was a decrease in activation in the right caudate nucleus when stimuli were judged very non-beautiful. However, this experiment, too, is subject to the criticism that the multi-exposure effect (stimuli were shown more than once) may have masked subtleties in the aesthetic judgments.
Importantly, the subjective psychological continuum between the beautiful and the not beautiful is not mirrored in the brain as such. In the brain, separate regions, pathways, and timings are applied. That which is “beautiful” engages direct processing while “ugly” is a passive process. Recently, Munar and associates (Munar et al., 2012) explored this issue with MEG and discovered that reaction to non-beautiful pictures occurs before reaction to beautiful pictures; upon viewing non-beautiful pictorial stimuli, the right lateral orbitofrontal lobe reacted within 300–400 milliseconds of withdrawal of the stimulus. The result confirms regional brain separation and timing for the subjective aesthetic valuation continuum.
Gombrich (1968) proposed that the attraction to forms and shapes in art, or in nature, lies in their biological relevance. Stebbing (2004) has further argued that the grammar of art is an extension of existing organic forms that play an important role in biology, evolution, and survival. Such basic art-organizing principles are contrast, rhythm, balance, and symmetry. These units, Stebbing argues, are the elements in the grammar of art used by artists to communicate and by the viewer to understand.
Along the same lines, it has been suggested that aesthetic interpretation of two-dimensional rendering in art is directly related to the elemental features in the art that the visual and perceptual systems are wired up to detect (Latto, 1995; Latto & Russell-Duff, 2002; Washburn, 2000). The greater the neuronal excitation upon viewing visual art, the greater the aesthetic response (Latto & Russell-Duff, 2002). Insight into this idea originated with the notion of anisotropy and the oblique effect. The oblique effect refers to inferior perception of patterns oriented obliquely as opposed to horizontally or vertically (McMahon & MacLeod, 2003). The effect has been found in human children and adults as well as in cats, monkeys, and other animals (Appelle, 1972; Baowang, Peterson, & Freeman, 2003; Friedrich, Harms, & Elias, 2014; Ishii, Okubo, Nicholls, & Imai, 2011; Shen, Tao, Zhang, Smith, & Chino, 2014). It has been suggested that the locus of the effect lies in the visual cortex rather than in the retina (Baowang et al., 2003; McMahon & MacLeod, 2003). One explanation for greater sensitivity to the preferred horizontal and vertical orientations rests on the early visual exposure to structures in the environment and the plasticity of the visual system. According to this view, there is greater prevalence of horizontal and vertical content in the environment than of oblique content, and, consequently, the experiential events sculpt the visual system to be more sensitive to horizontal and vertical orientations. The superior detection and recognition of these orientations over the oblique has been shown both in simple laboratory stimuli consisting of line gratings and in pictures of natural scenes (Coppola, Purves, McCoy, & Purves, 1998). Neuronally, more cells tuned to detecting horizontal and vertical patterns have been found than those responding to oblique orientations (Baowang et al., 2003). But inconsistencies in such findings have also been reported. On the whole, however, researchers agree that the oblique effect arises from cortical computations rather than retinal processing.
Oblique lines as opposed to non-sloping horizontal and vertical lines are not as aesthetically appealing (Appelle, 1972; Latto, Brain, & Kelly, 2000). Latto and associates have found that orientation of lines in paintings contributes greatly to aesthetic preference; component lines parallel to the frame were preferred over those that were not parallel. Piet Mondrian and the Dutch art school of De Stijl espoused the predominance of horizontal and vertical lines in eliciting aesthetic reactions (M. White, 2003). Latto and others have argued that the strong appeal in those orientations stems from a close match with what the visual and perceptual systems are tuned to detect, and the consequent level of neuronal activity. Thus, while abstract paintings by the De Stijl school do not depict figurative art, they do evoke strong aesthetic reactions. At the same time, Washburn (2000) points out that simple forms and shapes, not necessarily representational and not necessarily emphasizing horizontal and vertical lines (or orientations), are recognized and liked as well. The visual system reacts to components of form primitives in perceived shapes and the match between what is seen (form edges, say) and visual feature detectors explains reactions to art displayed on two-dimensional space (paintings, drawings, photographs, and so on).
The left–right organization of a pictorial layout has an influence on aesthetic preference as well. In photographed scenery, Levy (1976) has shown that observers prefer scenes where the most informative focal portion is in the right half. One group of observers first judged the most important portion in asymmetric vacation scenes. Then, another group of subjects, the raters, viewed these scenes and provided a preference judgment. Levy was interested in comparing performance between right-handed and left-handed subjects. She found that right-handed subjects aesthetically preferred the scenes where the informative locus was on the right half, regardless of whether or not the viewed scene was in the original orientation or mirror-reversed. With left-handed subjects there did not seem to be a significant left–right locus difference. The findings with right-handed subjects have been supported by other experiments that also used vacation scenes (Banich, Heller, & Levy, 1989). Beaumont used simple drawings to test the same idea, that of left–right organization and focal importance, and confirmed the right-side aesthetic preference (Beaumont, 1985). He proposed that what lies at the core of this preference bias is the movement of the gaze to the right side of the picture and the stimulation of the left visual half field: when a subject moves the eyes all the way to the right side, this results in more of the picture falling in the left visual half field and consequently preferentially engages the right hemisphere. According to this interpretation, specialization in visuospatial cognition in the right hemisphere and the notions of aesthetic judgment of pictorial representations are thus wedded. An alternative explanation for the right-side locus and aesthetic judgment is that it is the left hemisphere that becomes preferentially activated and that the aesthetic response is a reflection of that hemisphere’s cognitive apparatus (Heller, 1994). A further study found that side of emphasis in content of photographs interacts, thus complicating conclusions regarding the involvement of the right or left hemisphere alone in aesthetic decisions (Valentino, Brown, & Cronan-Hillix, 1988).
The foregoing described photographed vacation scenes, landscapes, and simple drawings; in contrast, the right-side bias does not square with established art works. Paintings in which the information emphasis was in the left side received aesthetic preference over those in which the emphasis was located in the right side (McLaughlin, Dean, & Stanley, 1983). Similarly, paintings in which the emphasis was in the right side did not necessarily receive greater aesthetic preference over those in which the emphasis was in the left side (Freimuth & Wapner, 1979). The role of either the left or the right hemisphere in aesthetic judgment is currently discussed in terms of reading habits (left to right, right to left, up–down; Van Houten, Chemtob, & Hersh, 1981).
Grusser has studied the lateral depiction of light sources in 2124 museum paintings from the fourteenth to the twentieth centuries (Grusser, Selke, & Zynda, 1988). He was interested in whether or not there is a left–right bias in light source depictions. He found that, while most paintings in the fourteenth century had diffuse illumination, a few showed clear left-side bias—that is, the light source originated in the left segment of the painting. This bias progressed consistently until it reached a peak in the seventeenth and eighteenth centuries, where about 70 percent of his sampled paintings showed this bias. In the nineteenth and twentieth centuries there was a major decline in this bias without a rise in a right bias. However, in the nineteenth century there was a steep rise in middle or diffuse light illumination so that 60 percent of his sample showed this trend. Grusser points out that this marks the time when artists began to question the convergent perspective and depth depictions; a lateral light source highlights the illusion of depth on a two-dimensional surface. And, he goes on to emphasize that ancient wall paintings from Pompeii and Herculaneum, and Byzantine mosaics in Ravenna churches, had a left light source bias. However, the left–right light source bias in paintings can be explained in terms of balanced composition, where the most important information is placed in the right half with the light shining upon it originating in the left half. Together, the laterality of the light source and the weight of important information in pictorial representations complement each other and give rise to a coherent work.
Aesthetic preference for paintings presented in the left or right visual half field reveals that no single hemisphere specializes in aesthetic responses (Buggio et al., 2012). Further, aesthetic responses under these hemi-field conditions were complicated by interaction between individual differences. Regard and Landis (1988) tested subjects in a hemi-field study that required an aesthetic decision between pairs of simple perceptual forms. They found an interaction between sex of subject and hemi-field of presentation for the preference judgments; women did not show a hemi-field difference for these figures while men showed a left visual field dominance for certain figures. Specifically, men seemed to prefer the figures that did not obey the gestalt law of simplicity and completeness (termed Pragnanz). The authors concluded that hemispheric aesthetic judgments were difficult to tease apart from interactions between sex of subject and cognitive/perceptual demands. In another hemi-field and aesthetics experiment by Landis and Regard, in which subjects saw faces in each visual half-field, the results were ambiguous with regard to hemispheric aesthetics (Regard & Landis, 1988). The authors agree that cognitive and aesthetic requirements interact with hemispheric specialization factors in ways that complicate conclusions regarding cerebral laterality of aesthetics. And, now with the surge of neuroaesthetic studies (discussed above), no clear-cut and consistent laterality effect has been elicited.
Beauty reaction to art could be viewed as an extension of responses rooted in biological human needs, such as attachment and care-giving (see review by Powell & Schirillo, 2009). Generalizing to parents and babies, most parents regard their own babies as being beautiful, more beautiful than the baby next door, more beautiful than their older brother’s baby (whom they originally regarded as beautiful), and even more beautiful than they were when they themselves were babies. In fact, such tiny babies can have wrinkled faces, with their skulls slightly misshapen (unless born by cesarean section); they grimace a great deal, keep their eyes closed, have some skin discoloration, and so on. Babies’ faces have what Konrad Lorenz has termed the “kewpie-doll” effect on adults (Kalat, 2002). The biology of the beauty response is further apparent in observations of parents judging their own infant’s pictures many years later, when the infant has grown to be an adult. The love and attachment attitude remains, but the original beauty judgment of that very early period has been altered. There might be a biologically active window for beauty responses in the period in which the child needs the greatest care.
What about beauty in painted portraits? For hundreds of years in Western art, starting with the Renaissance, artists have painted sitters’ faces with a slight turn of the head whereby a left–right asymmetry in the extent of side exposure is created, rather than with a head-on symmetrical view. Previously, artists depicted sitters in profile views. With women’s faces, the reason for the profile can be explained in relation to social attitudes dictating that virtuous women did not look directly at men (Brown, 2001). More broadly, the new artistic, societal, and intellectual developments in the Renaissance somehow contributed to the introduction of a slight turn of the head in sitters that ranged from a three-quarters view to only a quarter view, and even less than that (Lindell, 2013; Holbein’s head-on portrait of Henry VIII of England is highly unusual for that period).
In a study of painted portraits of single sitters displayed in the National Portrait Gallery in London, a sex difference in the side of the face that was emphasized was revealed (McManus & Humphrey, 1973). Women’s faces had a greater proportion than men’s faces of a left-side emphasis (68 percent versus 56 percent, respectively). There is no a priori reason why artists should favor women’s left sides more than their right or why they would want to emphasize the left significantly more often in women than in men.
An empirical attempt to understand the basis for the side bias in Western portraiture was launched many years after those results were first published (Zaidel & FitzGerald, 1994). The first key conjecture was that the principal determinant in the bias was a preference by the observer, particularly the paying observer (for hundreds of years, artists made a living through commissioned portraits). The working hypothesis was that observers liked to view women’s left side of the face more than the right, and that artists wanted to accommodate them. They wanted their works to be liked. They spent days, weeks, months, and even years on a given portrait (as was the case for Leonardo's Mona Lisa). The bias could not have been some random and haphazard event. Thus, it was important to determine the reasons behind viewers’ preference for certain portraits.
In the following experiment (Zaidel & FitzGerald, 1994), subjects in a laboratory were shown painted portraits of single sitters and asked to judge on a five-point scale the degree to which they liked the painting as a whole. A separate group of subjects were shown these portraits and asked to judge them on a five-point scale according to how attractive they considered the sitter. In each type of judgment requirement, one group of subjects saw the original orientation of the paintings and another group saw a mirrored version of the paintings. The unexpected findings were that in each type of judgment, regardless of whether the original orientation or its lateral reversal were shown, women sitters whom the artist originally painted with a right-side emphasis were preferred: the painting was preferred as a whole and the sitter was considered much more attractive than paintings where the left side was emphasized. Moreover, no significant left emphasis versus right emphasis was found for the male sitters, in each type of judgment. One would have expected at the very least that portraits of women with left-side emphasis would be the most preferred, since this is the Western trend in painted portraits. But the fact that sex difference emerged in the portrayed face indicated that the subjects picked up (unconsciously) an artistic bias after all. (There was no statistically significant sex difference in the judging subjects.)
These remarkable findings have led to a natural question regarding functional asymmetries in the face, particularly as they relate to face sex. A further study examined this question directly by photographing head-on views of people’s faces, then dividing the photographs down the vertical midline and creating two faces from each, one showing the left–left face and the other showing the right–right face (Zaidel, Chen, & German, 1995a). This was accomplished on a computer by creating a mirror image of a given half and aligning it with the original half so that, together, the original and its mirror image looked like a normal face (albeit perfectly symmetrical). Subjects in the laboratory were then asked to decide which one of the two faces, the left–left or the right–right, was more attractive or whether there was no difference between them. The results indicated that subjects preferred right–right over left–left in women’s faces and had no distinct preference between right–right and left–left in men’s faces. These results were consistent with the results from the portraits; together they suggest the presence of asymmetry in the appearance of beauty in the human face.
Going back to the artist’s studio, in making artistic decisions regarding the head turn in sitters, Western artists would have been influenced somewhat by reactions (to them, the artists) and responsivity in their sitters’ faces during small talk and conversation in the studio. The left side of the face is more reactive expression-wise than the right side, particularly in women. Men are more expressive in the left facial half than in their right half as well but the asymmetry is less striking than in women, possibly because men do not show strong facial expressions as readily as women do. Women smile more than men, for example (LaFrance, Hecht, & Paluck, 2003). The smile has been found to be strongly asymmetrical, being more salient in the left than the right facial half, as observed in 1872 by Charles Darwin (Darwin, 1998; Zaidel et al., 1995a). The right side of women’s faces, the attractive side, is not similarly reactive, and perhaps artists, most of whom were men, resonated to the smile and entered that unconscious perception into their conceptual artistic formula, and in so doing painted the essence of a positive reaction (reaction to the artist). This is what they wished to capture in their creation.
Human faces are in fact structurally asymmetrical and this has long been known from anatomical and craniofacial research (Ferrario, Sforza, Pogio, & Tartaglia, 1994; Ferrario, Sforza, Ciusa, Dellavia, & Tartaglia, 2001; Peck, Peck, & Kataia, 1991; Scheideman, Bell, Legan, Finn, & Reisch, 1980; Vig & Hewitt, 1975; Woo, 1931). Ancient Greek artists were aware of the asymmetry since they depicted it in sculptures of the human body and head. Ancient Roman artists copied Greek statues and were not observant enough to notice asymmetrical anatomical details or else chose to ignore them (Peck et al., 1991). With regards to emotional expressions in the face, as early as 1872 Charles Darwin reported on left-sided facial asymmetry, which he noticed in some emotional expressions while observing aboriginal people in Australia (Zaidel & Hessamian, 2010).
In neuropsychology, functional asymmetry in the face has been studied and reported for happy and sad expressions, both being more salient in the left side of the face (Borod, 1992; Borod, Haywood, & Koff, 1997). Smiling was found to be particularly salient in the left half of the face (Zaidel et al., 1995a). But the question of facial beauty and its asymmetrical organization, let alone any sex-related difference in that regard, had not been investigated until the question arose following the empirical studies into preferred depictions in painted portraits discussed above (Zaidel et al., 1995a). Indeed, showing subjects vertical hemi-faces and asking them to provide attractiveness ratings revealed no significant difference between the hemi-faces and the ratings of the full faces, thus indicating that facial symmetry is not an important factor in attractiveness (Van Dongen, 2011).
In recent years others have called the positive association between facial symmetry and attractiveness into question (Pound et al., 2014). An important study, involving a large number of subjects, investigated the relationship between childhood health and symmetry and discovered that there is no relationship between the two features (Harrison et al., 2015). The study’s authors concluded that symmetry in the face does not reliably predict physical health. The health, genes, and attractiveness link is currently on shaky ground. Similarly, in certain birds, the relationship between attraction to physiologically desirable males with a mating end goal and the quality of those males’ genes for subsequent generations has been questioned (Wallez & Vauclair, 2012).
Contrary to the symmetrical appearance of animals and prevailing biological views on the relationship between symmetry and quality of genes, in humans, asymmetry in the face (and skull, body, limbs) is the norm. Left–right directional asymmetry has a genetic and molecular underpinning and can be the basis for various physical abnormalities in humans (Levin, 2004; Varlet & Robertson, 1997). While animals can display body asymmetry, in humans this takes on significant value, particularly because of the association between the asymmetry and hemispheric specialization and handedness (see especially Bradshaw & Rogers, 1993; Hiscock & Kinsbourne, 1995). Consequently, finding sexually dimorphic functional asymmetrical organization for beauty in humans should perhaps not be surprising, particularly if we view it from an evolutionarily adaptive perspective, as has been proposed (Chen, German, & Zaidel, 1997; Zaidel et al., 1995a). The theoretical explanation lies in the signals relayed by the two sides of the owner’s face and the brain hemispheres of the observer; signals from each side are meant to be processed by two separate hemispheres of the observer so as to minimize interference in interpretation of the signals and increase efficiency of input processing. It is possible that attractiveness/beauty and emotional expressions represent mutually exclusive facial properties, and that they represent opposite ends of the spectrum of facial signals.
In face-on interactions, the right half of the owner’s face lies in the observer’s left visual and attentional field, which projects initially to the observer’s right hemisphere (the face specialization hemisphere), while the left half of the owner’s face lies in the observer’s right visual and attentional field, which projects information to the left hemisphere. So signals emanating from women’s right facial half are biologically meant to be processed by the functional specialization of the right hemisphere of the observer (a male, if considered from the perspective of biological advantage) while the left half of the face (which relays communicative signals through expressions) is processed by the left hemisphere as a sort of communicative signal. Anthropological studies do not place facial attractiveness in men at the top of the list of considerations of women choosing a mate, while facial attractiveness in women is at the top of the list for men choosing a mate (Buss, 1998). Left–right facial attractiveness asymmetry in men may not be an important biological factor for predicting health and survival potential of offspring.
Facial asymmetries, with greater salience of the expressions in the left facial half, have thus far been noted in rhesus monkeys (Hauser, 1993), macaque monkeys (Wallez et al., 2012), marmosets (Hook-Costigan & Rogers, 1998), chimpanzees (Fernandez-Carriba, Loeches, Morcillo, & Hopkins, 2002; Wallez & Vauclair, 2012), and baboons (Wallez et al., 2012). It has also been proposed (Zaidel et al., 1995a) that the selective adaptive pressures that shape the primate’s brain leading to hemispheric specialization in humans also shaped facial functional asymmetry (co-evolution); the face evolved to signal asymmetrical expressions and display, not only for the purpose of communicating verbal and non-verbal emotional expressions but also for the coordination of the whole body with a preferred hand dominance, as in the processes of carrying babies, holding tools, and throwing stones, as well as in coordinating bimanual activities.
Normally we are not conscious of these natural asymmetries because of their subtle presence. They emerge noticeably only under controlled laboratory conditions. The continuum of facial anatomical asymmetry is critical, then, since too much asymmetry interferes with the evolutionary biological purpose and borders on deformity.
We react to the beauty of blobs of color regardless of where we view them. Perhaps the reason we think sunsets in the great American Western skies or over the Pacific Ocean as viewed from a California hilltop are beautiful is not because of the colors in those sunsets but rather because of their unique luminance. There is very little color in gray, foggy days on rocky seasides, and, yet, such scenery elicits beauty-related reactions. There is no color in most of Ansel Adams’ photographs but they appear very beautiful to us. White marble statues from ancient Greek and Roman eras as well as from Renaissance times are three-dimensional art works; they have volume and depth, but no colors, and many of us consider them fantastically beautiful, even though they are at times disproportionately large. Stories told in black-and-white films appear just as beautiful as those told in color. Currently, the reasons for why this is so remain a mystery.
As stated previously in various sections of this book, color adds yet another dimension to art. In nature there is plenty of color everywhere, even in deserts. However, color is only one feature of the visual world that can convey meaning. To wit, color-blind people interact meaningfully with the world, and some are first-rate artists (see Chapter 3). Film is an exceptionally good example of art that does not need color to convey meaning and aesthetic appreciation.
The spectator experiences no shock at finding a world in which the sky is the same color as a human face; he accepts shades of gray as the red, white and blue of the flag; black lips as red; white hair as blond. The leaves on a tree are as dark as a woman’s mouth. In other words, not only has a multicolored world been transmuted into a black-and-white world, but in the process all color values have changed their relations to one another: similarities present themselves which do not exist in the natural world; things have the same color which in reality stand either in no direct color connection at all with each other or in quite a different one.
(Arnheim, 1958, p. 15)
The film is an art form that conveys remarkable meaning and elicits considerable aesthetic appreciation. Art represents concepts and humans deal with concepts every single minute of their existence. Humans can separate the representation of a concept from reality. The time when this distinction breaks down is in mental illness, in psychosis, for instance. In any case, before color film was invented, black-and-white films were the norm. For many years, even after color film became available, well-known film artists preferred to continue shooting motion pictures in gray-scale. In 1964, the film director Ingmar Bergman and the cinematographer Sven Nykvist made their first color film, All These Women, after years of making first-rate, highly acclaimed non-color films (see Chapter 3). This is what happened before they embarked on making it, as Nykvist (2003) tells it:
When Ingmar was going to make his first film in color, we made it a point to learn everything there was to know about color film. We even set up a color film school at the Swedish Film Institute in cooperation with Eastman Kodak. I shot over 6000 metres of Eastman color film in a series of tests. But, as I mentioned, technology is not all. Much of what I have studied comes from painting and still photography. In the preparation for Pretty Baby (1978), Louis Malle and I spent a lot of time studying Vermeer’s paintings, especially the way he uses light. The still photographer Ansel Adams is an idol of mine and I once made a pilgrimage to meet him. He too is known for waiting hours for the right light.
(Nykvist, 2003, p. 11)
In the end, All These Women was not received well by the critics (not necessarily because of the color), but the next color film that Bergman and Nykvist made, Passion of Anna, in 1969, was widely acclaimed; interestingly, the colors were muted, appearing in some sense to be monochromatic.
What the foregoing shows about beauty and aesthetic reactions to art is that the subject matter is not one of the elements in the reaction equation. Some other features in the art elicit the beauty in the mind of the observer. Real-life situations of illness never elicit such reactions. But illness in art is a different matter. The symbol in the art is distinguished from the reality. The art itself is what gives rise to the evocation.
Most of the research on brain activity and the art of dance deals with viewers’ reactions to dancing, particularly aesthetic (Calvo-Merino, Urgesi, Orgs, Aglioti, & Haggard, 2010; Cross, Kirsch, Ticini, & Schütz-Bosbach, 2011) and emotional reactions (Christensen, Gaigg, Gomila, Oke, & Calvo-Merino, 2014; Grosbras, Tan, & Pollick, 2012; Jola, Pollick, & Calvo-Merino, 2014). Other extensive discussions concern the neurocognition of dance in performing dancers (Bläsing et al., 2012); recently, over two hundred dance steps that can be used in studying dance were described (Christensen, Nadal, Cela-Conde, & Gomila, 2014). All of this has developed from work on healthy subjects. No opportunity for studying how elements of dance fractionate following brain damage seems to exist.
Aesthetic and emotional reactions to dance are wholly different from what we would expect the brain activity in the conceptual production of choreographed dances to be. A dance is not just body movements as in aerobic exercise, swimming, boxing, and so on. It is a motoric event consisting of many different movements that together deliver a coherent story, a story consisting of inter-related skilled movements, usually accompanied by music. Formulating a dance for dancers to perform recruits several areas in the brain of the choreographer, including areas where concepts are formed, areas giving rise to mental visualization of space (e.g., the right parietal lobe), the pre-motor and supplementary motor areas in the frontal lobes, and probably additional areas. It is an artistic ability that future studies could unravel.
Because of the physical movements dance involves, artifacts are easily introduced into any physiological measures attempting to determine the brain’s underpinning of dance. However, a few studies have managed to provide some insights into which brain areas are particularly active during some aspects of dancing (for a review see Karpati, Giacosa, Foster, Penhune, & Hyde, 2015). Three different techniques have been used so far—namely, EEG, positron emission tomography, and fNIRS (functional near-infrared spectroscopy). The dancing formats in these studies were not of entire ballets or of group folk dances or of other traditional and choreographed stories. Rather, the routines ranged from isolated movements with expressive or non-expressive features, tango steps involving only the legs, and dance video games. Despite unequal methodology, some commonalities emerged: activity was found in the cerebellum, putamen, parietal regions, pre-motor cortex, motor cortex in the pre-central gyrus, frontal lobe poles, and middle temporal gyrus. The involvement of the parietal lobe is to be expected given the spatial orientation required in dance movements; the frontal lobe involvement is expected given the planning ahead necessary in the movement routines; the motor-related regional activation is logical given the extensive motor control that is required in dancing; and, similarly, we would expect the cerebellum to be highly active given its role in coordinating disparate muscles of the body.
Art reflects the inner life of the artist not only by displaying talent, skill, creativity, experience, psychology, and cognition but also by mirroring emotional states. If art is an expression of the mind, then it is reasonable to wonder about the influence of emotional states on the final product. But emotional states can consist of moods, short or long term, for which there are cognitive strategies to overcome or to enjoy. Several moods can coexist at the same time. When artists compose a happy and exuberant musical piece, is this because they are happy and elated? We could argue that the opposite is true; the artist’s emotional state was down and depressed but, in order to extricate him/herself, the artist produced a happy piece. Paul Hindemith, a German composer and musician, is reported to have said that just because a composer works on funeral music it is no indication that he is in a melancholic mood throughout the composing (Trethowan, 1977). At the same time, there is no reason to assume that, in order to create such music, composers do not try to create a solemn mood within themselves, much as actors do when they apply the Lee Strasberg method to acting a character. Naturally occurring emotions and mood states in the composer, however, could enter into the formula of creation anyway. Hindemith offered a clue to this question: he claimed that when composers write, they know based on previous experience how to match the musical notes with mood evocation in the listener. He also pointed out that emotions invoked in the listener have different characteristics from emotions invoked by real-life situations, since emotions invoked by music are short lived, beginning with the onset of the music and terminating when the music no longer plays. In real-life situations, it is rare that we experience a timed beginning and ending of emotional states aroused by an external source. To some extent Hindemith is right. The strong emotions invoked by music are sustained while the music is playing. But some emotions remain afterwards, albeit at much reduced levels.
What is the anatomical underpinning of enjoyment upon reacting to art? What is the underlying neurophysiological reaction of “dislike” or “like” to art? Where in the brain is the activity the greatest? What processes in the brain give rise to aesthetic judgment, appreciation, enjoyment, and evaluation? If several brain systems are involved, which one acts first? What parallel processes are active? Viewing an artwork and liking and enjoying what is in front of us without knowing why exactly does not mean that our reaction is emotional. The absence of words does not necessarily mean emotion. The not-knowing-exactly-why state could be intellectual. Even with things that are purely intellectual, not all are understood with words or can be expressed with words. The sensation of liking a painting involves both cognitive (conscious and unconscious) and visceral reactions. Just because we are more aware of visceral changes does not mean that this is the only reaction we have, and it certainly does not mean that the reaction to art originates in the viscera. What we are aware of concerning the viscera is due to the action of the brain. Both emotional and cognitive responses originate in the brain computing what the senses perceive. Feeling visceral responses—tightening of the stomach, relaxed breathing—is possible because the viscera are represented in the somatosensory cortex. The awareness of feeling something in one way or another, as in reacting to an event or a stimulus, reflects multiple actions of the general arousal system, the reticular activation formation, the system involved in attention (because we are aware of how we are feeling), and the anterior insula, to name but a few. When it comes to assigning words to “feeling something,” this involves the left hemisphere and the language centers localized there. This does not mean that when we do not have words for feelings the right hemisphere is “doing the feeling” and the left is not.
Movies elicit emotional responses in viewers (Gross & Levenson, 1995; Shimamura, Marian, & Haskins, 2013), and there is cross-modal integration of auditory and visual information (Pehrs et al., 2014). A study measuring amount of cerebral blood flow during film viewing by female subjects revealed bilateral activation of the amygdala, a neuroanatomical brain structure critical for processing several emotions (Aalto et al., 2002). The stimuli consisted of 12 movie clips taken from When Harry Met Sally, Kramer versus Kramer, The Champ, and Bean: The Ultimate Disaster Movie. Together, the clips represented neutral, amusement, and sadness emotional categories, based on independently collected data from a separate group. Each clip lasted an average of two and a half minutes. The study indicated that several brain regions were involved in amusement and sadness reactions, including the temporal-occipital region, the anterior temporal lobe, and the cerebellum. Specifically, the researchers found for both amusement and sadness that the right temporal pole was active, as well as the amygdala bilaterally, and the cerebellum. They found little evidence for subcortical activation, except for the amygdala. Other studies using imaging techniques of brain activations are currently being used to delineate brain areas involved in emotional processing. The current consensus is that several brain regions become active during emotionally related tasks (Shobe, 2014).
Many functional brain-imaging techniques overlook the fact that, although experiments such as these are designed to measure emotional reactions, they also recruit cognitive components. It is not trivial or simple to separate emotions from cognition. The regions that have been found to be active to date in emotion experiments are localized in the neocortex as well as in subcortical regions; the cortical regions are known to be active when non-emotional cognitive tasks are administered. If all the activity seen in the brain during emotion-related experiments were restricted to subcortical structures alone, it would be reasonable to deduce that the experiments truly tapped emotional reactions. Since this has not been so, one needs to assume that the emotional content of the stimuli have cognitive components. It is only logical to infer the involvement of cortical regions in emotional reactions. One of the theories of emotions, known as the James–Lange theory, presupposes a rational, conscious reasoning for being in a particular emotional state (Lang, 1994): verbal labels determine the conscious awareness of the emotion. For example, sensations of trembling are interpreted to mean fear, sensations of quickened heart pace are interpreted to mean being happy in anticipation of seeing someone special, smiling is interpreted to mean being happy, and so on. The body may react before the conscious verbal label is assigned but the name of the emotion and the interpretation imply involvement of cognitive cortical centers. This situation could be unique to humans and suggests an interactive cognitive loop for emotional reactions.
Since art represents the context and environment of the artist, the perceptions, experiences, ideas, and insights, it is reasonable to expect similarity or, at the very least, a natural continuum in the brain between emotional reactions to non-art stimuli and to art. Asymmetries in hemispheric specialization for emotions have been reported for both healthy patients and patients with unilateral brain damage (Lee et al., 2004; Rashid, Clarke, & Rogish, 2013; Shobe, 2014). Separate emotions are evident with unilateral hemispheric damage. Following right hemisphere stroke there is a preponderance of euphoria, indifference reactions, and denial of illness, whereas damage to the left hemisphere is often accompanied by depression (Gainotti, 1972). These opposite types of emotional valances indicate that emotion is not a unitary process, and this is consistent with the notion that there is a cognitive, cerebral component to its expression. If emotions were controlled solely by subcortical structures, the evolutionarily old brain parts, we would not see the coloring of the emotions through the neocortex—that is, through human cognition. As an example, a study of 141 patients with unilateral stroke in the left or right hemispheres revealed that the preponderance of depression reactions were in the left hemisphere group (Paradiso, 1999; Paradiso, Ostedgaard, Vaidya, Ponto & Robinson, 2013).
The fact that humans interpret their emotional reactions in terms of their contextual source attests to the fact that cognitive features play a role in emotions. The interaction of the two can serve as a theme, a guiding principle for future behavior. Extending the discussion to what humans describe as “feeling guilty” illustrates the interaction of morality and society’s rules and emotions. There is a developmental sequence to empathy, which suggests that cognitive features of yet another non-verbalized reaction are a component of emotional reactions (Leslie, Johnson-Frey, & Grafton, 2004). Reactions to facial expressions are processed in brain areas similar to those modulating face identification and recognition, namely the fusiform area in the right hemisphere (Cowell & Cottrell, 2013; Kanwisher & Yovel, 2006). The right hemisphere specializes in processing faces for recognition and identification (LaBar, Crupain, Voyvodic, & McCarthy, 2003; Posamentier & Abdi, 2003). But there is some evidence that this lateral specialization changes in older adults (Gunning-Dixon et al., 2003) and there is a suggestion that not all emotional reactions to facial expressions are uniform—that is, hemispheric-selective activation co-varies with type of expression (Kilts, Egan, Gideon, Ely, & Hoffman, 2003). In any case, both hemispheres are characteristically involved in emotional reactions, albeit the reactions take on different “colors” depending on the nature of the emotion.
As described earlier, art productions commonly express social, cultural, political, and personal happenings (conscious and subconscious). Capturing responses to such surroundings in images is meant to convey meaning and thereby elicit reactions. This reaction is initially in the emotional domain but does not have to imply lack of understanding of the symbolism, whether the art is realistic, impressionistic, or abstract, despite the reaction not immediately being available to logical or linguistic analysis.
It has previously been proposed by the author that art and beauty are interconnected through the biological adaptive mechanism of attraction-attention to the art. The function of beauty, then, is to attract attention to what is on display. This chapter reviewed the issues of beauty, aesthetics, and emotions, and concluded that beauty reactions are independent of the degree to which reality is represented, thereby suggesting beauty’s anchor in biology and neuroanatomy.
The chapter discussed several issues: the idea that beauty is an emergent property of art, the issue of alterations in aesthetic preference following brain damage and how these alterations can be explained in terms of an obsessive–compulsive disorder, pleasure and the reward system, the oblique effect and properties of the visual cortex, hemispheric aesthetic preference, the biological nature of beauty in faces, painted portraiture, facial asymmetry and art, emotions of the creating artist versus those of the viewer, emotional reactions in the brain to films, and hemispheric laterality of emotions
The surge in neuroaesthetic research in the past 10 years has revealed important facts about the neural pathways and brain regions that become engaged in aesthetic reactions. Multiple regions and widely distributed pathways appear to be involved in the reactions. The activated regions are widespread and are known to support diverse forms of cognition, suggesting that aesthetic reactions are not simply emotional nor solely meant to elicit pleasure. Emotional reactions to life events are not diametrically opposite to reactions to art. Since art represents the context and environment of the artist, it is reasonable to expect a great similarity or, at the very least, a natural continuum between emotional reactions to non-art stimuli and art stimuli. But the issue of pleasure in aesthetic reactions to art is itself difficult to pin down because the reactions are brief, do not seem to have the same value as pleasure arising from physiological sources, seem to lack primary motivational goals, and easily succumb to habituation.
The sources that give rise to aesthetic reactions are numerous. For example, the left–right organization of viewed images plays a role in aesthetic reactions. Focal components in the right half of photographed landscapes have greater influence on aesthetic judgment than ones in the left half. On the other hand, paintings, rather than photographs, in which the information emphasis is in the left side have been found to receive aesthetic preference. Facial beauty is asymmetrically organized on the face with the emphasis being located in the right half, but this is so only in women’s faces; in men’s faces there is no left–right difference in appearance of beauty. Research on painted portraits and photographed faces seems to concur on this sex difference with regards to the organization of beauty in faces.
Color is not a critical aesthetic component of art although it does add yet another dimension to it, one that should be studied separately. Film is an exceptionally good example of art that does not need color to convey meaning and aesthetic pleasure. For many years, even after color film became available to filmmakers, well-known film artists preferred to continue creating motion pictures in gray-scale. The film director Ingmar Bergman and the cinematographer Sven Nykvist provide examples discussed in this context.
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