Subconscious Cognition?! What you don’t know, might help you…or it might not!

Subconscious Cognition?!

What you don’t know, might help you…or it might not!

Perception and Cognition

• We have elaborate perceptual mechanisms to provide information to our brains to guide current or future behavior



• Notice there’s no mention of consciousness




• Lot’s of information gets processed and used by your brain without you noticing




• Lot’s of information gets processed and used by your brain without you noticing

• Consider some examples

Masked Priming

Masked Priming

S P A MTIME

XXXXX

Masked Priming

S P A MTIME

S P _ _

XXXXX

Masked Priming

S P A MTIME

Masked Priming

• Subject must complete the stem to make any word other than the word that was masked

Masked Priming

• Subject must complete the stem to make any word other than the word that was masked

• Subjects are more likely to use masked word…indicates subconscious influence on behavior

Blindsight and the Dorsal Stream

• Patients with lesions to primary visual cortex occasionally retain some visual abilities:– better than chance performance on forced-

choice discrimination tasks– spatial navigation and coordination (i.e. avoid

obstacles, interact with environment)


• Patients with lesions to primary visual cortex occasionally retain some visual abilities:– better than chance performance on forced-choice

discrimination tasks– spatial navigation and coordination (i.e. avoid

obstacles, interact with environment)• Thought to be because of other “backdoor” pathways

that send signals to the Dorsal Stream, A.K.A the “Where and How Pathway”


• The Dorsal Stream is thought to mediate much spatial processing and interaction with the environment

“WHAT”

“WHERE”


• The Dorsal Stream is thought to mediate much spatial processing and interaction with the environment

• But the neural activity in these structures does not (is not alone sufficient to) enter into consciousness

The Hard Problem Returns

• MYSTERY: what is special about neural activity that leads to awareness ?

NOBODY KNOWS !

Vokey & ReadS T U D Y

l a n i m i l b u Ss e g a s s e M

Two Themes

• What were the two themes of this article?

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)?

Subliminal Messages

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

Subliminal Messages

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

Subliminal Messages

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

– words embedded in the background of images

Backmasking

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

Backmasking

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

• controversy in the 80’s - subliminal “backmasked” messages in rock music

Backmasking

• Examples of Gary Greenwald’s demonstrations (warning: you are about to hear a backmasked “message”)

Forward Backward

Does Backmasking Work?

• What can subjects tell about backwards messages?


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


• What don’t backwards messages convey?


• What don’t backwards messages convey?

–Meaning


• 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.)


• The meaning of backmasked messages is not consciously perceived (sufficiently to enable performance on these tasks).

• Might such messages still influence behavior?


• 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 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?



• Result: there was no biasing of the less frequent homophone by exposure to it in a backward 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



• What are some counterarguments one might make?



• What are some counterarguments one might make?– Perhaps repeated exposure is necessary



• What are some counterarguments one might make?– Perhaps repeated exposure is necessary– Null findings do not prove the absence of an

effect



• 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

Are All Subliminal Messages Intentionally Inserted?

• These messages tend not to be clear and obvious


• These messages tend not to be clear and obvious

• Could it be that our brains mistakenly see or hear messages that aren’t really there?


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

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?


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

The “subliminal” message is:


• 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”


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

• Listeners detected “messages” in the appropriate passage


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


• 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


• 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”


• 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

Expert Testimony !


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


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

Viking, 1976


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

Mars Global Surveyor, 2001

Summary

Sensory Signals

Sensory Memory

Short-Term Memory

Long-Term Memory

ATTENTION

REHEARSAL

RETRIEVAL

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Subconscious Cognition?! What you don’t know, might help you…or it might not!