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Some provocative questions. Does natural selection still work in our highly artificial society? What will the homo sapiens be like in another 200.000 years? (Why are there mental illnesses, if adaptationism is so powerful in evolutionary psychology?). Freud, Sigmund.
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Some provocative questions • Does natural selection still work in our highly artificial society? • What will the homo sapiens be like in another 200.000 years? • (Why are there mental illnesses, if adaptationism is so powerful in evolutionary psychology?)
Freud, Sigmund • What do Freud and Evolutionary psychology have in common? • The Unconscious
The realm of unknown: implicit knowledge and learning Budapest Semester in Cognitive Science Cognitive Psychology Day 2.
But before anything else • Provo is a picturesque region of France. • Corman was a pretender to the throne of Provo. • He was tired of waiting. • He thought arsenic might work. Try to remember these!
Look at these pictures Now look carefully at these pictures. You will need to recall them later.
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Memory • How come? • Malfunctions • Experimental data • The Atkinson-Schifrin-model
Famous Anterograde Amnesiac: HM • Severe epilepsy, treated with surgery to bilaterally remove medial temporal lobes, including hippocampus • Operation 9/1953, 27 years old
Anterograde Amnesia • Inability to acquire new information • “Memento” • Does not affect short-term memory and general knowledge from the past • It is difficult to learn new facts • Affects memory regardless of modality (visual, auditory, tactile, etc). Spares skilled performance
Cat Apple Banana Hammer Toothpick Parrot Table Blackberry Fly Chair Screw Pigeon Orange Knife Bed Dog Fork Rat Try to recall as many items as you can!
Primacy effect Recency effect
Peterson’s STM Task • Test of memory for 3-letter nonsense syllables • Participants count backwards for a few seconds, then recall • Without rehearsal, memory fades
Voices of dissent - again • Two systems? Dissocition studies: • STM & LTM tests differ: • Non-word repetition test • Word list learning • Presentation rate • Meaningfulness • Can there be a clear division line? • Is there an alternative path – crossing out STM entirely?
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Memory
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Memory
There is more than we can tell… • Eidetic pictures of children How many stripes did you see on the cat?
Sensory Memory Sensory Input Sensory Memory Store • Function - holds information long enough to be processed for basic physical characteristics • Capacity - large • can hold many items at once • Duration - very brief retention of images • .3 sec for visual info • 2 sec for auditory info
Sensory Memory Store • Visual or iconic memory was discovered by Sperling in 1960 • It is only conscious in part – not all of it • Sensitive to eye movement • Bright background following it (mask)
Sperling’s Experiment • Presented matrix of letters for 1/20 seconds • Report as many letters as possible • Subjects recall only half of the letters • Was this because subjects didn’t have enough time to view the entire matrix? No • How did Sperling know this?
High Medium Low Sperling’s Experiment • Sperling showed people can see and recall ALL the letters momentarily • Sounded low, medium or high tone immediately after matrix disappeared • tone signaled 1 row to report • recall was almost perfect • Memory for image fades after 1/3 seconds or so, making report of entire display hard to do
Sperling’s Iconic Memory Experiment G V U L S J N A Z A M K X F Q O U N
Is the fading effect evolutionarily adaptive? • Would we not be better off like Funes, the famous rememberer of Borges’ short story? • Theories of forgetting: lack of encoding, decay, interference, retrieval failure (cue) • Why is forgetting adaptive? • What is the role of consciousness? • Can short presentations of stimuli be effective – and have a lasting effect? • N.B.: you can not consciously recall the letters!
Long lasting effects of short exposures to stimuli • Facial expressions • 18-30 ms presentation • Unconscious effect • Judged neutral faces to be more pleasant • Höschel et al. 2001 Priming studies
Around 15% of children Lasts around 40 seconds More susceptible to interference More likely to create false memories! Leads to the question – how much trace do non-conscious events leave in normal population? Eidetic memory
Subliminal ads • Subliminal is defined in two ways • Embedded figures of text, not obvious to superficial examination (picture ads) • Short exposure times (television or movies)
The question of subliminal advertisements Wilson Bryan Key: Subliminal Seduction and Media Sexploitation
James Vicary - priming • 1957 – subliminal advertising • Eat popcorn • Drink Coca-Cola • Embedded in a film (0,03s cuts) increased sales by 20-60% • However he never published this finding • Later in an interview he claimed that this was a fabrication • No one could reproduce it in its original
Critique • Moore: weak effects and strong effects • Weak effects – over emotions – improbable because of the competition with various supraliminal stimuli • Strong effects – over buyer behaviour – improbable because of the control over one’s behaviour
Subliminal advertising is banned in most English-speaking countries • Yet many self-help audiotapes containing subliminal messages are sold • Self-esteem, weight loss, memory enhancement • even though many studies failed to find evidence that they work • mind you: these are double blind studies! • Also they contain far too long sentences to be processed linguistically – see priming studies (Greenwald, 1992) – Brand names?
Placebo • Most companies deny that they use subliminal ads • Yet 74% of people believe in it • 71% of those who believed in it thought it works as well • Rosenthal effect? (Cassandra-type or self-fulfilling prophecy)
New evidence • Revival after 2000 – new studies • Cooper and Cooper (2002) • Subliminally primed people with pictures of Coca Cola cans and the word thirsty • Their self-rated thirst rose • Dijksterhuis et al (2005) • Subliminally primed drink&cola and neutral words • Exp group drank more, but no difference is what
Karremans et al (2006) • Self-rated thirst • Primed with Lipton Ice or neutral words (Npeic Tol – same letters) for 23 ms • In pilots they found that usually the prime can not be guessed – not conscious • Allegedly, they were supposed to partake in a detection task • BBBBbBBBBB – how many small bs? • Choice between Lipton Ice tea (Coke being too sweet or too popular – brand loyalty) and Spa Rood
Direct emotional priming • Strahan et al. (2005) • Subliminal priming will only affect people’s choices if they are goal-relevant • It affects attitude to bevarages, BUT only if the person is thirsty! Higher evaluation • Bargh (1996) • Trait priming – the person is only going to be rude after the priming, IF (and only if) given the possibility
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Memory
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Long-Term Memory • Capacity unlimited • Thought by some to be permanent • Encoding transfers info from STM to LTM –semantically organized basis • Anterograde amnesia
Amnesia • Types of amnesia • Anterograde • Retrograde
Retrograde amnesia • Temporal gradient: • early memories are better remembered than memories before trauma (Ribot’s law) • Recently formed memories continue to undergo neurological change: memory consolidation • Retrograde amnesia often becomes less severe over time • Most remote memories are likely to return first • Does not affect overlearned information (e.g. skills)
Anterograde Amnesia • Inability to acquire new information • Think of movie “Memento” • Does not affect short-term memory • Does not affect general knowledge from the past • But, it is difficult to learn new facts • Affects memory regardless of modality (visual, auditory, tactile, etc). Spares skilled performance • Hyper-specific memory for those skills that are learned after onset – learning is expressed only in context in which it was encoded
Our hero anew: HM • Severe epilepsy, treated with surgery to bilaterally remove medial temporal lobes, including hippocampus • Operation 9/1953, 27 years old
Spared (implicit) learning in anterograde amnesia • Claparede study (1911). • Patient never remembered having met Claparede (doctor) before • Claparade offers handshakes with pinprick • Next time, no explicit memory of event (or doctor) • Still, patient refuses to shake hands and offers explanation: “sometimes pins are hidden in people’s hands” • Korsakoff patients & Trivia questions • Given feedback, then retested. No conscious memory for items but better performance. “I read about it somewhere”. (Schacter, Tulving & Wang, 1981).
H.M • General knowledge intact but “stuck in time”. • Did not learn words introduced after 1953: “jacuzzi”, “granola”, “flower-child” • Was able to form some memories • Initially couldn’t learn how to get to his new home. Took many years to learn his own house • However it is not true that he was simply incapable of learning at all
HM able to mirror trace improvement in H.M. for mirror tracing task (without conscious recollection of previous training episodes) the medial temporal lobes are not necessary for all types of long-term memory. Milner, 1965
Amnesics can learn to mirror-reverse read and are sensitive to repetitions
A Taxonomy of Memory Systems LONG TERM MEMORY EXPLICIT (declarative) IMPLICIT (non-declarative) SEMANTIC (facts) EPISODIC (events) PRIMING (perceptual, conceptual) PROCEDURAL (skills & habits) ASSOCIATIVE LEARNING (classical & operant conditioning) Medial Temporal Lobe Cortex Striatum Amygdala/ Cerebellum
Implicit and explicit memory • Implicit memory: past experiences influence perceptions, thoughts & actions without awareness that any information from past is accessed • Explicit memory: conscious access to info from the past (“I remember that..” ) -> involves conscious recollection
Proof for dissociation in brain injured • Can the same be shown for healthy adults?
Healthy amnesiacs? • Visual search task with repeated items • Search the letter T! • Effect of midazolam / similar to LTM deficit