Cognition

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Cognition The Visual Arts
Dr. Thomas Shaffer Psychology 492 South Dakota
State University
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Psychology Art

• Cognition Psychology (the science of the mind) is
  the study of how the mind processes information.
• The Cognitive Revolution that swept through
  psychology during the second half of the second
  century captured the interest of a generation of
  scientists disenchanted with traditional
  behavioral psychology and psychoanalysis.
• In the last 50 years Cognitive Psychologists have
  produced an impressive collection of data about
  how humans perceive, process, and store
  information.
• However, while Cognitive Psychology has made
  spectacular discoveries during the past 50 years,
  art is one of the most glorious of human
  achievements.

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The Glory of Art Human Existence

• Decorative arts have graced the lives of people
  throughout the ages.
• Art is found in some shape or form in all
  cultures!
• long before psychologists contemplated the basic
  nature of mental existence, or philosophers
  contemplated the meaning of life, prehistoric man
  drew images on cave walls or created primitive
  human figurines.
• Art is part if human existence and we are part of
  art!
• Art cognition are indeed two convex mirrors
  each reflecting amplifying the other.

L. Woman From Willendorf, Austria. C.
30,000-25,000 BC. Limestone, 4/12 ins. High. R.
Man from Brno, Czech, Republic, C. 30,000-25,000
BC. Ivory, 8 ins. High
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Art Mind are one!

• Mind Art are one, when we create or experience
  art we have a clear experience of what
  philosophers would call mind.
• That is, we do not see art, we see through
  the minds eye and translate that experience
  into some type of artistic expression.
• In the platonic tradition, what we experience is
  an interpretation of the world around us, not a
  direct experience.
• Thus our perceptual world is a highly individual
  unique experience.
• Thus art is a highly personal and unique
  experience for each human interpreter that can
  differ with each new exposure

Vincent Van Gogh. The Night Café, C. 1880. Oil on
Canvas
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Cognition the Visual Arts

• This course is a reflection of what is currently
  known about the nature of human perceptual
  cognitive systems and visual art.
• It is about the way the eye and mind see,
  understand, and respond to visual art.
• We will study visual science, visual physiology ,
  the perceptual organization of the visual
  world.
• We will study the relationship between eye
  movements and art, and the evolution of the
  visual system
• We will study neurophysiology and how the brain
  organizes and integrates information from all of
  out senses to produce the esthetic experience.
• We will study how each of us brings to the
  viewing of art his or her own unique experience
  how that experience can change from moment to
  moment

Vassily Kandinsky, Improvisation No. 30, 1913.
Oil on Canvas
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The Descent of Man
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The Evolution of Man

• The evolution of Mankind has occurred over a
  period of at least 4.5 million years
• Primitive humanoids originally came migrated from
  the African continent, through Europe, and
  eventually into North America.
• Homo Sapiens, our closest ancestors, first
  appeared on the continent some 40,00 years ago
  following the end of the last interglacial
  period.

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The Evolution of Homo Sapiens

• Early Homo Sapiens had larger Brains than
  previous humans, and the climate changes that
  followed the last interglacial period led to a
  significant increase in the food sources
  available to him.
• This allowed man to thrive, and to develop
  sophisticated social culture, although he
  remained primarily a hunter/gatherer

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The Beginnings of Primitive Art
Although Humanoids had almost certainly created
decorative art, perhaps as long ago as hundreds
of thousands of years previously, the earliest
know sophisticated art has been found in Europe,
and dates back 25,000 to 30,000 years.
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Early Primitive Art

• Themes in the earliest known artistic works
  consist of hunting scenes and the depiction of
  animals.
• This perhaps is a reflection of mans hunting and
  gathering culture that was dominant at this
  period of time

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Early Human Art The art of the Hunters
Left section of the Lion Panel, 25,000-17,000 BC.
Pigment on Limestone. Near Chavet, France
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Early Human Art The art of the Hunters

• Hyena Panther, C. 25,000-17,000 BC. Pigment on
  Limestone Rock, Chauvet Valley, France

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Early Human Art The art of the Hunters

• Bison after 15,000 BC. Modelled Clay, near
  Ariege, France

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Early Human Art The art of the Hunters

• Spear Thrower Carved with Leaping Horse, 12,000
  BC, Montastruc France

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Early Human Art The art of the Hunters

• Coyote Head, 10,000 BC, Bone, Tequixquiax, Mexico

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Early Human Art The art of the Hunters

• Two Giraffes and an Elephant Superimposed, C.
  8000-5000 BC. Rock Engraving, Messak, Libya

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Early Human Art The Art of the Farmers
Engravings on Rock. C. 8000. Found near Palermo,
Sicily
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The Art of the Farmers

• a

Man from Cernavoda, C. 4000-35000 BC. Clay,
Bucharest, Romania
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The Art of the Farmers
Stonehedge, C. 2100-2000 BC. Salisbury Plain,
Englande
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The Art of the Farmers
Entrance to Temple, C. 3000-2000 BC. Malta
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• a

Goddess in Childbirth, C. 1500 BC, Valley of
Mexico?
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Visual Perception Structure of the Visual System
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The evolution of the Mammalian Visual System

• The human eye has evolved over millions of years
  in order to allow us to see in a 3 dimensional
  world (even though our system encodes a 2
  dimensional image).
• Vision is an adaptive skill, that is, our
  specific visual system is tuned to the
  environment that we live in.
• Our visual system is different than creatures
  that live in our world because it is specific to
  our needs.

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Structures of the human eye
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Visual receptors in the retinal layer are
connected to bipolar cells which in turn are
connected to ganglion cells. This allows for a
progressive discrimination of visual information
at a very early level in the system.
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The Retina

• The earliest Stage of visual processing occurs in
  the Retina
• The retina contains the visual receptors that
  allow us to transduce stimulus energy from the
  environment into the electro-chemical signals the
  brain can interpret.
• Transduction is carried out by two types of cells
  in the retina, Rods (Which code for luminance) ,
  and Cones (which code for color).

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Visual Angle

• Vision is best within 12 degrees of visual angle
  from center because of the concentration of
  cones in the Fovea.
• Foveal Vision subtends less than 2 degrees of
  visual angle, parafoveal vision subtends another
  10 degrees of visual angle
• Near peripheral visual angle subtends the next 60
  degrees of visual angle, and peripheral vision
  constitutes 180 degrees of visual angle

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Visual Perception Color Perception
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Light consists of charged electromagnetic
particles moving in waves. The mammalian visual
system is tuned to a certain portion of the light
spectrum.
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Rods Cones

• Rods and Cones are the sensory receptor cells of
  the mammalian visual System.
• Cones allow us to see color there are three
  types, short wave, medium wave, long wave. They
  also allow us to resolve fine detail (visual
  acuity)
• Cones are found in the fovea or center of the
  retina, there are roughly 7 million.
• Rods allow us to see in black white, and to see
  lines, angles, and contours.
• Rods are found outside the fovea. There are
  roughly 100 million of them.

Exterior of a cone
Interior of a Cone
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Response ranges of the visual receptors

• Rods Cones have different response ranges
• This graph represents the overall responses of
  the two types of visual receptors to the visual
  spectrum

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The maximum responses of the three cones may be
demonstrated on a visual tuning curve
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Do all people see color the same way?

• For centuries people have debated the question,
  is one persons subjective experience the same as
  anothers
• Certainly, the phenomenon of color blindness has
  been of interest since John Dalton, a natural
  scientist and professor of mathematics reported
  in 1790 that his perceptions of color seemed to
  be different that that of others.
• Dalton believed that the lenses in his eyes was
  possible tinted, differently that other persons
• He solved the question by willing his eyes post
  humorously to Oxford University

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Color Blindness

• Different types of impairment in color vision can
  lead to different appearances of color in the
  visible spectrum

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Color Blindness

• The reproductions of a Monet were drawn by 1) a
  person with normal color vision, 2) a person with
  a red green color deficiency, and 3) and person
  with a lesion in the portion of the brain that
  processes color

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Visual Perception Luminance Perception
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Luminance

• Luminance, or what artists refer to as value is
  perceived lightness (brightness)
• It is defined by how the human visual system
  responds to light
• In particular, how bright the average human
  judges a light to be
• Luminance is not a physical measurement, and the
  luminance of any particular number of photons
  varies depending on the wavelength of light, it
  is determined by how sensitive our eyes are to
  that color of light.
• Understanding luminance is important because out
  perception of depth, three-dimensionality,
  movement, and spatial organization are all
  carried by part of our visual system that
  responds only to luminance differences and is
  insensitive to color

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Luminosity Response Curve The apparent
brightness of different wavelengths of light in
Daylight

• A Luminosity Response Curve shows the combined
  responses of the three cone types of light to
  each wavelength.
• The two arrows show that under daylight
  conditions, a given amount of blue light (450 nm)
  produces about 1/20 the response as the same
  amount of green light.
• This occurs because our visual systems is less
  sensitive to blue than to green light (the
  spectral luminosity function is lower in the blue
  than in the green spectrum)

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Luminosity Response Curve Apparent brightness of
different wavelengths (Day vs. Night).

• Rods, like cones, have a spectral response cure.
• The response of rods varies both with the amount
  of light and with the wavelength. Rods are much
  more sensitive to luminance than cones
• You can see on this curve that the rod curve
  peaks closer to the short wavelength end of the
  visual spectrum (e.g. rods peak lower in the blue
  spectrum than the combined cone spectrum, meaning
  the brightest part of the spectrum is different
  for rods).

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Luminance Art

• This comparison of Picassos the Tragedy with a
  black white version shows the paintings
  lightness value
• There is not much difference in these prints,
  this thus reveals how much information is carried
  by luminance alone.

Picasso, The Tragedy (Poor People on the
Seashore), C. 1903
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Luminance Art

• Monets Famous Impressionist sunrise (1872.) was
  widely disparaged by critics in Paris.
• The original version above appears to pulsate.
• As the black white version indicates the sun is
  exactly the same luminance as the rest of the
  painting.
• In the third version (right) the sun has been
  made lighter than in the original, but it has now
  lost its luminosity and paradoxically appears
  less bright