2nd Nose
You can use either hand, but this is the left hand, as seen from the back.]]Cross
your middle finger behind your index finger. The index finger is sometimes called
the pointer finger-- it's the finger right next to your thumb. The fingers should be
touching near, but not at, the tips. It doesn't matter which hand you use.

Bring your crossed fingers to the tip of your nose. Place your fingers so
that the tip of your nose is in the small space or gap between the two
fingertips. If you're using your right hand, the right side of the tip of your
middle finger and the left side of the tip of your index finger should be
touching your nose; if you're using your left hand, this will be reversed. You
will probably notice a strange sensation, as though you have two noses.

Run your crossed fingers slowly up and down the
bridge of your nose. If you haven't already felt the
two-noses sensation, you likely will now, as your
motor brain is tricked into thinking that each finger
is focused on a separate nose.[2]
Chapter 6: Perception
Perception
Selective
Attention:
the focus of
conscious
awareness on a
particular stimulus.
Selective Attention
The
most famous
example to illustrate
selective attention is
known as the
“cocktail party
effect.”

http://www.huffingtonpost.com/2012/06/20/silent-gorilla-studyconcentration-deaf_n_1612843.html?utm_hp_ref=science&icid=mainggrid7%7Cmain5%7Cdl5%7Csec1_lnk3%26pLid%3D171994
Testing Selective Attention –
remember this activity?

http://www.echalk.co.uk/amusements/OpticalIllusions/motionBli
ndness/motionBlindness.html

Haircut
http://www.youtube.com/watch?v=veD-BzCyHJc
Brain Games color
http://www.youtube.com/watch?v=JwdgjI4Dxng
Perception
Visual
Capture:
refers to the
tendency for vision
to dominate the
other senses.
Perceptual Organization
 Gestalt:
an organized whole.
 Gestalt
psychologists
emphasize humans’ tendencies
to integrate pieces of
information into meaningful
wholes.
 Things
are not seen as sum of
parts but immediately as
wholes.
Top-down
Processing
You may start
to see
something in
this picture if
we give your
brain some
concepts to
apply:
“tree”
“sidewalk”
“dog”
“Dalmatian”
Perceptual Organization
 Figure-Ground
Relationship:
tendency to organize
information into objects
(figure) that stand out
from their
background(ground)
Figure Ground
Relationship
Gestalt Psychology
 Grouping:
the perceptual tendency to
organize stimuli into coherent groups
 Grouping Principles:
Proximity
Similarity
Continuity
Closure
Connectedness
Proximity: tendency to group nearby
figures together

Similarity: tendency to group figures
that are similar

Continuity: tendency to perceive
continuous patterns

Closure: tendency to fill in the gaps in
visual information.
Closure
Connectedness: spots, lines and areas
are seen as unit when connected

Grouping examples
Which grouping principle do you
see in this picture?
Illusionary Contours: We constantly
filter information so it makes sense to
us.
Depth Perception
 Depth
Perception: the
ability to see objects in
three dimensions.
Allows us to gauge
distance.
 Visual Cliff:
illustrated that crawling
infants and newborns
perceive depth.
Visual Cliff: A Test of Depth Perception
Babies seem to develop this ability at crawling age.
Even newborn animals fear the perceived cliff.
Types of Depth Perception
 Binocular Cues: depth cues that rely on the
use of two eyes.
 Examples of Binocular Cues:
Retinal Disparity: idea that images of an
object from the two eyes differ. The closer
the object, the larger the difference
(disparity.)
Convergence: extent to which the eyes
converge inward when looking at an object
that brain keeps track of to measure
distance.
Types of Depth Perception
 Monocular
Cues: distance cues that are
available to either eye alone. Often used in
art.
Monocular Cue:
Relative Size
We intuitively know to
interpret familiar objects (of
known size) as farther away
when they appear smaller.
Monocular Cue: Interposition
Interposition:
When one object
appears to block the
view of another, we
assume that the
blocking object is in a
position between our
eyes and the blocked
object.
Monocular Cues: Relative
Clarity
Hazy object
seems more
distant
Monocular Cues: Texture
Coarse = close
Fine = distant
Monocular Cue: Relative
Height
We tend to perceive
the higher part of a
scene as farther away.
 This scene can look like
layers of buildings, with
the highest part of the
picture as the sky.
 If we flip the picture,
then the black part can
seem like night sky…
because it is now
highest in the picture.

Monocular Cues:
Relative Motion
When we are moving,
we can tell which
objects are farther
away because it takes
longer to pass them.
A picture of a moon on
a sign would zip behind
us, but the actual moon
is too far for us to pass.
Motion Perception
We perceive motion in many ways.
Objects moving toward us
We perceive this motion by watching the changing
apparent size of an object.
 Objects moving to one side
We perceive relative motion, although we often judge
huge objects inaccurately. In what way? Why?
 Objects traveling in a more complex path, such as
in an arc through the air coming toward us
Baseball players, and even dogs, can run right to
where a fly ball is going to land by keeping the ball
in a constant apparent position in the sky.

Monocular Cues:
Linear Perspective and Interposition
The flowers in the
distance seem
farther away
because the rows
converge. Our brain
reads this as a sign
of distance.
Tricks Using
Linear
Perspective
These two
red lines
meet the
retina as
being the
same size
 However, our
perception of
distance
affects our
perception of
length.

Monocular Cues: Shading
Effects – Relative
Brightness
Shading helps our
perception of
depth.
Does the middle
circle bulge out or
curve inward?
How about now?
Light and shadow create depth cues.
Monocular Cue?
Monocular Cue?
Monocular Cue?

What Cues Do You See?
How many Legs?
Perceptual Constancy

Perceptual Constancy: perceiving objects as unchanging
despite changes in retinal image
color
shape
size
Shape Constancy
What shape do you see outlined in red?
Interplay Between Perceived Size and
Distance

Using monocular cues for distance can often cause us to
perceive incorrect information.
Diameter of Circles Are the Same
CONTEXT EFFECT
double pear
Spelling test answers:
apple payor
payee pair
Did context affect which word you wrote?
Muller-Lyer Illusion
Cultural Influences on Depth Perception

Impossible Image
Impossible Staircase
Warm Up

http://www.youtube.com/watch?v=KApieSGlyBk
Sensory Deprivation and
Perception
 Blind
Person Example
Some
aspects of perception
might be innate
Others involve experiences
 Critical
period for
development of sensation and
perception
Sensory Deprivation and Perception
Kittens raised
without
exposure to
horizontal lines
later had
difficulty
perceiving
horizontal bars.
Perceptual Adaptation
 Perceptual
Adaptation
(vision) ability to adjust to an
artificially displaced visual field
prism glasses
Perceptual
Interpretation
 Perceptual
Set: a mental
predisposition to perceive
one thing and not another.
 What you see in the middle
is influenced by if you
looked at bottom or the top
Lochness Monster or a Tree Trunk?
Perceptual Set Affects Other Senses
 Perceptual
Set also affects other senses like
audition.
Ex: eel is on the wagon vs. eel is on the
orange.
CONTEXT MATTERS!
Rat Man
Lyrics
Perception and the
Human Factor
 Human Factors Psychologistsexplore how people and machines
interact and how machines and
environments can be adapted to human
behaviors
Is there Extrasensory Perception?

Extrasensory Perception: claim that perception can occur
apart from sensory input.
Astrological
predictions, psychic healing,
communication with the dead
Telepathy-
mind to mind
Clairvoyance-
Precognition-
perceiving remote events
perceiving future events
Psychokinesis-
mind over matter
Example-
light as a feather stiff as a board
Is there Extrasensory Perception?
 Parapsychology:
study of paranormal
phenomenon, including ESP and psycho kinesis.
 Research
Psychics not accurate
More predictions- police work
Vague predictions
Lottery
No experiment has EVER produced a convincible
demonstration of ESP
Phi Phenomenon

Blinking lights give the illusion of motion