Idea Journals Due on Thursday You may hand in: Printed pages if they are stapled or otherwise bound together Hand written pages so long as the writing is legible Not possible to hand these in late!

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

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

Blindsight and the Dorsal Stream The Dorsal Stream is thought to mediate much spatial processing and interaction with the environment “WHAT” “WHERE”

Object Substitution Masking Masking occurs when one stimulus impairs perception of a nearby stimulus In special cases the stimuli don’t have to overlap in space or time!? Object substitution masking occurs when attention cannot select a target object before it vanishes …AND… A mask is visible at the target location after the target has vanished

Object Substitution Masking

Surprisingly, some visual information survives masking Subjects are accurate at reaching to grasp a masked shape even though they can’t consciously see it

Masked Priming Surprisingly even the meaning of visual information can survive some kinds of masking

Masked Priming S P A M TIME

XXXXX Masked Priming S P A M TIME

S P _ _ XXXXX Masked Priming S P A M TIME

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

The Hard Problem Returns MYSTERY: what is special about neural activity that leads to awareness ? NOBODY KNOWS !

Vokey & Read S T U D Y l a n i m i l b u S s 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?

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

Does Backmasking Work? What don’t backwards messages convey?

Does Backmasking Work? What don’t backwards messages convey? –Meaning

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.)

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?

Does Backmasking Work? Priming by backmasked message?

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

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?

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

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

Does Backmasking Work? Priming by backmasked message? What are some counterarguments one might make?

Does Backmasking Work? Priming by backmasked message? What are some counterarguments one might make? –Perhaps repeated exposure is necessary

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

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

Are All Subliminal Messages Intentionally Inserted? These messages tend not to be clear and obvious

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 aren’t really there?

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 aren’t really there? Do brains make stuff up!?

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 aren’t really there? Do brains make stuff up!? Absolutely! All the time.

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?

Are All Subliminal Messages Intentionally Inserted? Some other examples brains making guesses with your perception Missing fundamental, color constancy, Kaniza triangle,the blindspot, illusory conjunctions, misinformation effect, false memories

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?

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:

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”

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

Subliminal “Messages” Where you Least Expect Them Interpretation: Your brain is remarkably good at “active construction” of patterns amid a background of noise.

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

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”

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

Expert Testimony !

Subliminal “Messages” Where you Least Expect Them With enough creativity and patience one can see “subliminal messages” just about anywhere:

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

Subliminal “Messages” Where you Least Expect Them Given a clearer picture it looks a lot less like a face: Mars Global Surveyor, 2001

Summary Senso ry Signal s Sensory Memory Short- Term Memory Long- Term Memory ATTENTION REHEARSAL RETRIEVAL