Be not afeard; the isle is full of noises,
Sounds and sweet airs, that give delight and hurt not.
Sometimes a thousand twangling instruments
Will hum about mine ears, and sometime voices
That, if I then had waked after long sleep,
Will make me sleep again: and then, in dreaming,
The clouds methought would open and show riches
Ready to drop upon me that, when I waked,
I cried to dream again.
CALIBAN, The Tempest, III, ii
What is darker, the red of an apple or a strawberry?
What is the color of envy?
What is directly below the window of your bedroom?
What angle do the hands of a clock make at 9:00 pm?
How may degrees does the minute hand of a clock
travel between 6:00 pm and 6:30 pm?
• What city is more West, San Diego or Las Vegas
• Imagery simulates perception
• Imagery incorporates language based
• Imagery incorporates heuristics or best guesses
Imagery: A Little History
• Binet 1880’s
– Based on patients with brain damage, he suggested that imagining a
movement draws on motor processing, imagining a form or a color
draws on object recognition or color systems.
• Introspectionists
– Equipped with stopwatches and fountain pens, tried to time how it
takes for an image to come to consciousness.
– Argued if one could think about a thing without conjuring its image
– If memories using imagery lasted longer than those that did not.
• Imagery was treated as one homogeneous ability in a host of
complex processes from chess games (Cleveland, 1907) to
helping children learn to read (Hill, 1918).
Imagery: A Little History
• the Perky Effect
– In the now classic study, CW Perky (1910) asked participants
to imagine an object (a banana) while fixating onto a blank
screen. At the same time unbeknownst to the participant , an
image of that object was gradually projected onto the screen,
with increasing intensity, starting below the threshold for
conscious perception.
– The projected stimulus influenced the subjects’ experience so
that their images changed according to the picture they were
presented with.
– They all continued to believe the they were just imagining the
stimulus when the intensity was above threshold, for example
they remarked the banana was vertically and not horizontal as
they originally imagined, or imagined an elm leaf when they
first started with a maple.
Imagery Demo
Are these balloons identical?
Imagery Demo
Are these balloons identical?
• Roger Shepard and the Isomers
The object below is an isomer
Imagery Theories
• Dual Coding Hypothesis
– There are two codes in the brain, one verbal and
one visual based
• Propositional Theory
– The visual and verbal symbols are propositions
• Depictive or Functional Equivalency
– Imagery and perception recruit the same processes
• Picture you are dot on the letter F
• Imagine traveling along the
• You are going to be asked to
imagine traveling along the
pathway and stating whether the
corner you reached is on the top
or the bottom
Demo Time!
• Please memorize the following sentence
A bird in the bush is not in the hand
You are to go through each word, in order, and
tap your right hand if the word is noun, and
your left if it is not
Demo Time
• Please read through
the words in this
box out-loud
• Please point to each
“YES” in order
Evidence for Dual Code Theory
• Paivio compared concrete words (potato,
horse) with abstract words (justice, love)
• Found participant were better able to recall
concrete words
• Concluded that dual code was created for
concrete words (analog & verbal label) but not
for abstract words
Additional Evidence for Dual Code
• Visual information has different characteristics
than verbal code
– Visual information interferes with spatial
– Verbal labels interfere with spoken words
– Shows each type of code is affected by different
Evidence for Dual Code Theory
• Brooks (1968)
– One group saw a block
diagram of a letter
– Memorized it
– Were asked to mentally travel
the letter and indicate if the
corner was on the extreme top
or bottom
Evidence for Dual Code Theory
• Brooks (1968) cont.
– Second group saw a
– Memorized it
– Were asked to classify
each word as a noun by
indicating "yes" or "no"
– Verbal task
A bird in the hand is
not in the bush
Evidence for Dual Code Theory
• Brooks (1968) cont.
• Participants were then asked
to respond in one of two
– Say “Yes” or “No”
– Point to the answer “Yes or
– Why was this important?
Yes No
Yes No
No Yes
Evidence for Dual Code Theory
• Brooks (1968) Results
Letter Diagrams
11.3 sec.
28.2 sec.
13.8 sec.
9.8 sec.
For letter task, RT was slower when pointing.
For the sentence task, RT was slower for the verbal response.
This provides evidence for two types of codes being used.
Propositional Theory
• Do not store in form of images
• Instead have a “generic” code that is called
– To imagine a ball on top of a box would require a
string statement: ON (BALL, BOX)
• Stores the meaning of the concept
• Create a verbal or visual code by transforming
the propositional code
Propositional Imagery Demo
• Imagine a die standing on one of its corners,
and draw it.
• What color does a red light and a green light
• Imagine a straight line rotating 90o. Imagine a
cross rotating 90o
Depictive or Functional Equivalency
• Same brain areas are involved in perception
and imagery
Depictive Imagery Demo
Depictive Imagery Demo
Depictive or Functional Equivalency
• Memorize map
• Later ask to scan image
• Manipulate distance between
items in scan
– Hut to grasses
– Lake to Hut
• Measure reaction time
Depictive or Functional Equivalency
• Linear relationship between the distance to
scan and actual reaction time of participants
– Mental images are internal representations that
operate in a way that is analogous to the
functioning of the perception of physical objects
Evidence for Depictive Imagery
• Linear displacement (e.g., Island)
• Scaling (e.g., Rabbit Elephant)
• Deficits in perception parallel deficits in
• Visual Fill
• Imagery scanned for previously unrecognized
Evidence for Depictive Imagery
• Visual Fill
Figure 1. Degradation in visual fill due to homonymous hemianopia, the
surgical removal of a portion of the visual cortex. Patients report that the
size of the visual image experienced decreases in proportion to the
amount of tissue removed.
Evidence for Depictive Imagery
• Look at the image below
• Did you see the goose? • Did you see the sparrow?
Depictive Imagery: Tricks you can do with
a Brain!
Imagery of the Hemispheres
(Apologies to Galileo)
• The “Coordinate-Categorical
Specialization” Theory
– Left Hemisphere specializes in Categorical
(on, in, beside, above, below…)
– Right Hemisphere specializes in Coordinate
(3 ft., 45o, 10 lbs…)
Imagery of the Hemispheres
• Do the hands of a clock make an angle bigger
or smaller than 60o?
– 12:01
– 11:56
– 8:27
• Are both hands above or below the midline?
– 10:03
– 9:05
– 6:34
Imagery of the Hemispheres
• Show a clock they can see
• Show a digital time they have to
imagine as a clock
Imagery of the Hemispheres
• A small advantage for coordinate
processing in the RH.
Be Here Now
• Please draw a map that shows the cities of
L.A., San Francisco and Reno, NV.
Be Here Now
• Please Draw a map of the world.
Sports Visualization
Sports Imagery
• Three purposes
– Skill
– Strategic
– Motivational
Sports Imagery
• Initial learning Hypothesis
– Mental practice should have its greatest impact at the initial
verbal-motor stage of learning
• Psychoneuromuscular Hypothesis
– The muscles fire at a low grade level of the same pattern
during the mental practice as the physical practice.
• Attentional Hypothesis
– mental practice can aid ignoring distracters and prime
attention on important cues and at important junctions in
Sports Imagery
• The same imagery task will be used differently
by athletes of different levels. Visualizing
yourself practicing a skill will be…
– motivational when you are a novice
– Skill-building as an intermediate
– Strategy-building or attentional as an expert