Cracking the code of art’s allure
Anthony Freeman, managing editor, Journal of Consciousness Studies
Figure 1. The accentuated features of a bronze statue of the Indian
goddess Parvati (circa 11th century A.D.), amplify the essence of the feminine to
produce a “peak shift effect”.
Figure 2. Grouping: the Dalmatian emerges from a random jumble of
splotches, producing a pleasing sensation.
Figure 3. A caricature of Richard Nixon by the French cartoonist Mulatier.
Figure 4. The savant syndrome: horses drawn by Leonardo da Vinci (right)
and by an eight-year old autistic child.
|
The eight laws 1 |
A bold new theory to
identify the common denominator of all visual art
‘If a Martian ethologist were to land on earth and watch us humans, he
would be puzzled by many aspects of human nature, but surely art—our propensity to
create and enjoy paintings and sculpture—would be among the most puzzling. What biological
function could this mysterious behaviour possibly serve?
“Cultural factors undoubtedly influence what kind of art a person enjoys. But, even
if beauty is largely in the eye of the beholder, might there be some sort of universal
rule or ‘deep structure’, underlying all artistic experience?”
Vilayanur S. Ramachandran, Director of the Center for Brain and Cognition at the
University of California at San Diego, has made a bold and controversial attempt
to answer these intriguing questions by proposing a new scientific theory of art.
The theory explains many familiar experiences, such as why a cartoon squiggle can
evoke a well-known face more quickly than a full colour photograph, and why many
men find the hour-glass figure of Marilyn Monroe sexy.
Professor Ramachandran’s theory addresses three questions: (a) What are the “rules
of art” that make something pretty? (b) Why did these rules evolve and have the form
that they do? (c) What is the brain circuitry involved? Previous theories of art
have looked at one or two of these questions, but this is the first time all three
have been tackled together.
With his colleague William Hirstein, Ramachandran proposes a list of “Eight laws
of artistic experience . . . that artists either consciously or unconsciously deploy
to optimally titillate the visual areas of the brain,” in particular that part of
the brain known as the limbic system. Of the eight (see box),
three seem to be especially significant: a psychological phenomenon called the “peak
shift effect”; the principle of “grouping”; and the benefit of focusing on a single
visual cue.1
The ‘peak
shift effect’
The “peak shift effect”
is a well-known principle in animal discrimination learning. For example, if a rat
is taught to discriminate a square from a rectangle and rewarded for the rectangle,
it will soon learn to respond more frequently to the rectangle. Moreover, if the
rat is trained with a prototype rectangle of, say, aspect ratio 3:2, it will respond
even more positively to a longer and skinnier figure—say, of aspect ratio 4:1. This
curious result implies that what the rat is learning to value is not a particular
rectangle but a rule: rectangles are better than squares. So the greater the ratio
between the long and the short sides, i.e. the less square-like it is, the “better”
the rectangle is in the rat’s eyes. This is the “peak shift effect”. Ramachandran
argues that this principle holds the key for understanding the evocativeness of much
of visual art.
How does the peak shift effect relate to human pattern recognition and aesthetic
preference? Consider the way in which a skilled cartoonist produces a caricature
of a famous face, say the late U.S. President Richard Nixon’s. What a cartoonist
does (unconsciously) is to take the average of all faces, subtract it from Nixon’s
face (to get the difference between Nixon’s face and all others) and then amplify
the differences to produce a caricature. The final result, of course, is a drawing
that is even more Nixon-like than the original. The artist has amplified the differences
that characterize Nixon’s face in the same way that an even skinnier rectangle is
an amplified version of the original prototype that the rat is exposed to. Hence
Ramachandran’s aphorism that “All art is caricature”. (This is not literally true,
as he admits, but it applies surprisingly often.) In other words, what the artist
tries to do is not only capture the essence of something but amplify it in order
to activate neural mechanisms more powerfully than the original object.
Look at the Chola bronze—the accentuated hips and bust of the Goddess Parvati (Fig.
1) and you will see at once that this is essentially a caricature of the female form.
Here the artist has chosen to amplify the “very essence” (called the rasa by Hindu
artists) of being feminine, by moving the image abnormally far toward the feminine
end of the female/male spectrum. The artistic amplification produces a “super stimulus”
to which, Ramachandran conjectures, certain brain circuits respond. Artists may also
try to evoke a strong direct emotional response by exploiting the peak shift effect
along dimensions other than form. For instance, a Boucher, a Van Gogh, or a Monet
may be thought of as a caricature in “colour space”.
Perceptual
grouping and binding
A second basic principle
suggested by Ramachandran is “grouping” (or binding). The way this works can be illustrated
by the Dalmatian dog picture shown in Fig. 2. This is seen initially as a random
jumble of splotches. The number of potential groupings of these splotches is infinite,
but once the dog is seen, your visual system links only a subset of these splotches
together and it is impossible not to “hold on” to this group of linked splotches.
Indeed, the discovery of the dog and the linking of the dog-relevant splotches generates
a pleasant “aha” sensation. In “colour space” the equivalent of this would be wearing
a blue scarf with red flowers if you are wearing a red skirt; the perceptual grouping
of the red flowers and your red skirt is aesthetically pleasing. Artists understand
the pleasure given by such effects.
The evolutionary value of such grouping of stimuli to pick out objects is obvious:
it makes the detection of both prey and predators much easier. But how is such grouping
achieved? The key idea is as follows. Given the brain’s limited attentional resources
and shortage of neural space for competing representations, every stage in the processing
of visual information offers an opportunity to generate a signal that says, “Look,
here is a clue to something potentially object-like!” Partial solutions or conjectures
to perceptual problems are fed back from every level in the hierarchy to every earlier
module to impose a small bias in processing, allowing the final percept to emerge
from such progressive “bootstrapping”.
Consistency between partial high-level “hypotheses” and earlier low-level ensembles
generates a pleasant sensation—e.g. the Dalmatian dog “hypothesis” encourages the
binding of corresponding splotches which, in turn, further consolidate the “dog-like”
nature of the final percept and we feel good when it all finally clicks in place.
And what the artist tries to do is to tease the system with as many of these “potential
object” clues as possible—an idea that would help explain why grouping and “perceptual
problem-solving” are both frequently exploited by artists and fashion designers.
Isolating
a visual signal
The third principle (in
addition to peak shift and binding) emphasized by Ramachandran is the need to isolate
a single visual modality before you amplify the signal in that modality. The brain’s
ability to do this explains why an outline drawing or sketch is more effective as
“art” than a full colour photograph. Consider a full-colour illustration of Nixon,
with depth, shading, skin tones and blemishes, etc. What is unique about Nixon is
the form of his face (as amplified by the caricature), but the skin tone—even though
it makes the picture more human-like—
doesn’t contribute to making him “Nixon-like” and therefore actually detracts from
the efficacy of the form cues. This explains why one not only “gets away” with just
using outlines—they are actually more effective than a full-colour half-tone photo,
despite its having more information. Hence the aphorism “more is less” in Art.
Additional evidence for this view comes from the “savant syndrome”—autistic children
who are “retarded” and yet produce beautiful drawings. The animal drawings of the
eight-year-old artist Nadia, for instance, are almost as aesthetically pleasing as
those of Leonardo da Vinci (Fig. 4). Ramachandran argues that this is because the
fundamental disorder in autism is a distortion of the “salience landscape”; savants
shut out many important sensory channels, thereby allowing them to deploy all their
attentional resources on a single channel.
‘Lie detector’
testing
Ramachandran believes that
the “peak shift principle” can be tested directly. The method would employ skin conductance
response (SCR), the technology used in “lie detectors”. The size of the SCR is a
direct measure of the amount of limbic (emotional) activation produced by an image.
It is a better measure, as it turns out, than simply asking someone how much emotion
they feel about what they are looking at, because the verbal response is filtered,
edited, and sometimes censored by the conscious mind. Measuring SCR allows direct
access to “unconscious” mental processes.
The experiment would compare a subject’s SCR to a caricature of, say, Einstein or
Nixon, to his SCR to a photo of the same individuals. Intuitively, one would expect
the photo to produce a large SCR because it is rich in cues and therefore excites
more modules. If one found, paradoxically, that the caricature actually elicited
a larger SCR, this would provide evidence for the operation of the peak shift effect—the
artist would have unconsciously produced a super stimulus.
Critical
responses
Ramachandran says that
one could also compare the magnitude of an SCR to caricatures of women (or indeed,
to a Chola bronze nude or a Picasso nude) with the SCR to a photo of a nude woman.
It is conceivable that the subject might claim to find the photo more attractive
at a conscious level, while registering a large “unconscious aesthetic response”—in
the form of a larger SCR—to the artistic representation. That art taps into the “subconscious”
is not a new idea, but our SCR measurements may be the first attempt to test such
a notion experimentally.
Not surprisingly, Ramachandran’s attempt to reduce aesthetic experience to a set
of physical or neurobiological laws has already met with stout criticism. A symptom
of trouble to come has been seen in his use of the term “pretty”. If used at all
by serious art critics, the word damns with faint praise. Prettiness is not seen
as a synonym for beauty, but as a shallow impostor. Yet Ramachandran uses it without
irony as a positive attribute. This one piece of unfortunate terminology might be
forgiven, but other elements in his work are all of a piece with it.
First, there is the heavy reliance on the female form and upon the erotic in his
examples. Then he seems to equate “arousal” (as measured by SCR) with a positive
aesthetic response—an assumption felt by critics to presuppose the reductionist case
he is trying to prove. Taken together, these points seem to some critics to confuse
pornography with high art.
The “science of art” has also been attacked from the scientific side, on the grounds
that its proponents have not yet conducted any serious empirical tests of their ideas.
At best they have offered a manifesto for a research programme and made some suggestions
for possible lines of investigation. Even then, it has been pointed out that the
narrow range of examples used hardly justifies the lofty claims to be dealing with
the whole of art, let alone to have uncovered the “laws of aesthetic experience”.
Nor has hitching his bandwagon to the Buddhist train, by associating his “eightfold
laws” with the Buddha’s eightfold noble path won Ramachandran any friends, though
to be fair, he admits himself that this is a slightly whimsical association.
Criticism has centred on the lack of proportion between the narrow approach to art
taken by Ramachandran and the grandiloquent claims he makes for his theory—although,
as he admits, he initially proposed it “in a playful spirit”. But the very audacity
with which its author propounds it guarantees that we shall be hearing a lot more
of it in the coming months.
1. V.S. Ramachandran and William Hirstein are publishing a fuller
exposition of this subject later this year in the Journal of Consciousness Studies
under the title “The Science of Art, A Neurological Theory of Aesthetic Experience”.