You may turn in your journal at the end of class

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You may turn in your journal at the end of class
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Vokey Read
l a n i m i l b u S s e g a s s e M
S T U D Y
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Two Themes

• What were the two themes of this article?

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Two Themes

• What were the two themes of this article?
• 1. Do so-called subliminal messages work?
• 2. Is it possible that not all messages were
  put there by evil rock stars (or Satan)?
  

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Subliminal Messages

• What two kinds of subliminal messages do the
  authors investigate?

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Subliminal Messages

• What two kinds of subliminal messages do the
  authors investigate?
  
• backmasking - backwards messages in songs

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Subliminal Messages

• What two kinds of subliminal messages do the
  authors investigate?
  
• backmasking - backwards messages in songs
• words embedded in the background of images

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Backmasking

• Backmasking is not backward masking (if youre
  going to argue that some perceptual phenomenon is
  the work of Satan, at least get the name right)

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Backmasking

• Backmasking is not backward masking (if youre
  going to argue that some perceptual phenomenon is
  the work of Satan, at least get the name right)
  
• controversy in the 80s - subliminal backmasked
  messages in rock music
  

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Backmasking

• Examples of Gary Greenwalds demonstrations
  (warning you are about to hear a backmasked
  message)

Forward
Backward
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Does Backmasking Work?

• What can subjects tell about backwards messages?

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Does Backmasking Work?

• What can subjects tell about backwards messages?
• Sex of the speaker
• Language (barely)
• Different speaker (barely)

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Does Backmasking Work?

• What dont backwards messages convey?

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Does Backmasking Work?

• What dont backwards messages convey?
• Meaning

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Does Backmasking Work?

• Some Examples of the experiments that Vokey
  Read did
  
• Subjects were presented with various phrases
  played backward. Subjects were unable to
  
• Accurately discriminate between questions and
  declarations
  
• Sort sentences into the category of message
  (i.e. satanic, Christian, nursery rhymes, etc.)
  

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Does Backmasking Work?

• The meaning of backmasked messages is not
  consciously perceived (sufficiently to enable
  performance on these tasks).
  
• Might such messages still influence behavior?

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Does Backmasking Work?

• Priming by backmasked message?

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Does Backmasking Work?

• Priming by backmasked message?
• Subjects presented with passages that use the
  less common of two homophones tend to use that
  word when asked to spell it
  
• e.g. climbing Mt. Everest is an incredible feat

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Does Backmasking Work?

• Priming by backmasked message?
• Subjects presented with passages that use the
  less common of two homophones tend to use that
  word when asked to spell it
  
• e.g. climbing Mt. Everest is an incredible feat
• Subjects heard backwards sentences containing
  uncommon words
  

If backwards messages have subliminal influence,
what would you predict?
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Does Backmasking Work?

• Priming by backmasked message?
• Result there was no biasing of the less frequent
  homophone by exposure to it in a backward message

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Does Backmasking Work?

• Priming by backmasked message?
• Result there was no biasing of the less frequent
  homophone by exposure to it in a backward
  message
  
• Interpretation backmasked messages are not
  effective at influencing behavior

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Does Backmasking Work?

• Priming by backmasked message?
• What are some counterarguments one might make?

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Does Backmasking Work?

• Priming by backmasked message?
• What are some counterarguments one might make?
• Perhaps repeated exposure is necessary

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Does Backmasking Work?

• Priming by backmasked message?
• What are some counterarguments one might make?
• Perhaps repeated exposure is necessary
• Null findings do not prove the absence of an
  effect

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Does Backmasking Work?

• Priming by backmasked message?
• What are some counterarguments one might make?
• Perhaps repeated exposure is necessary
• Null findings do not prove the absence of an
  effect
  
• one needs to know the statistical power

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Are All Subliminal Messages Intentionally
Inserted?

• These messages tend not to be clear and obvious

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Are All Subliminal Messages Intentionally
Inserted?

• These messages tend not to be clear and obvious
• Could it be that our brains mistakenly see or
  hear messages that arent really there?

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Are All Subliminal Messages Intentionally
Inserted?

• Is there really a dog or are the spots enough
  like a dog for your brain to fill in the rest?

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Subliminal Messages Where you Least Expect Them

• How did Vokey and Read test the idea that
  subliminal messages might just be a case of
  mistaken perception?
  

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Subliminal Messages Where you Least Expect Them

• They examined passages from various sources
  (Jabberwokey and the 23rd Psalm) played backwards
  to identify candidate messages
  

The subliminal message is
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Subliminal Messages Where you Least Expect Them

• They examined passages from various sources
  (Jabberwokey and the 23rd Psalm) played backwards
  to identify candidate messages
  

The subliminal message is saw a girl with a
weasel in her mouth
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Subliminal Messages Where you Least Expect Them

• Listeners were given each passage (backwards) and
  asked to listen for 12 possible messages
  
• Listeners detected messages in the appropriate
  passage
  

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Subliminal Messages Where you Least Expect Them

• Interpretation Your brain is remarkably good at
  active construction of patterns amid a
  background of noise.
  

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Subliminal Messages Where you Least Expect Them

• Interpretation Your brain is remarkably good at
  active construction of patterns amid a
  background of noise.
  
• Creative listening by (well-meaning?) public
  censors can go very wrong
  

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Subliminal Messages Where you Least Expect Them

• Consider the trial of Judas Priest
• Band sued for inserting the message do it which
  allegedly lead to the suicide of two teens
  

Listen for Do It
The do its
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Subliminal Messages Where you Least Expect Them

• Consider the trial of Judas Priest
• Band sued for inserting the message do it which
  allegedly lead to the suicide of two teens
  
• Band acquitted on the basis of expert testimony

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Expert Testimony !
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Subliminal Messages Where you Least Expect Them

• With enough creativity and patience one can see
  subliminal messages just about anywhere
  

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Subliminal Messages Where you Least Expect Them

• Our perceptual mechanisms are great at extracting
  meaningful images from noisy stimuli. For
  example - the famous face on Mars
  

Viking, 1976
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Subliminal Messages Where you Least Expect Them

• Given a clearer picture it looks a lot less like
  a face
  

Mars Global Surveyor, 2001
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Summary