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Cognitive psychology. Rosie IVÁDY. Course schedule. 9-10.30 lecture 10.30-10.45 break 10.45- 12.15 lecture 12.15-12.45 lunch break 12.45-13.30 talking seminar. Course requirements. Test on Friday at 9.00 Multiple choice questions True/false questions
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Cognitive psychology Rosie IVÁDY
Course schedule • 9-10.30 lecture 10.30-10.45 break 10.45- 12.15 lecture 12.15-12.45 lunch break 12.45-13.30 talking seminar
Course requirements • Test on Friday at 9.00 • Multiple choice questions • True/false questions • Slides can be found on my homepage the day following class at • www.cogsci.bme.hu/~ivady
Day 1 – Unconscious knowledge, memory and learning. Evolutionary psychology inborn? • Day 2 – Psycholinguistics, language and thought • Day 3 – Theory of mind and the teleological stance. Evolution of language and theory of mind • Day 4 – Social and pathological. Religion and mental health. Morals, taboos, and the Penal Code
The realm of unknown: implicit knowledge and learning Budapest Semester in Cognitive Science Cognitive Psychology Day 1.
Memory and learning • Today’s features: • Memory – conscious and unconscious • Learning – is there implicit learning? • Implicit cognition – its social and practical perspectives
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Memory
Sensory Memory Sensory Input Sensory Memory Store • Divided into two subtypes: • iconic memory - visual information • echoic memory - auditory information
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)
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
Priming studies • Facial expressions (emotional priming) • Unconscious effect • 18-30 ms presentation • Judged neutral faces more unpleasant • Höschel et al. 2001
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Encoding Long-term memory Attention Sensory Input Retrieval Memory
Sources • Blow to head, Concussion • Korsakoff syndrome (severe vit. B1 deficiency) • Alzheimer’s • Damage to hippocampus, thalamic structures • ECT (electroconvulsive shock therapy) • Midazolam: artifically induced 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
Famous Anterograde Amnesiac: HM • Severe epilepsy, treated with surgery to bilaterally remove medial temporal lobes, including hippocampus • Operation 9/1953, 27 years old
Two systems? Dissocition studies: • STM & LTM tests differ: • Non-word repetition test • Word list learning • Presentation rate • meaningfulness
Hebb : dual trace mechanism • Cell assembly and • reverbarating activity – STM • Atkinson & Schiffrin: • One might consider the short-term store simply as being a temporary activation of some portion of the long-term store.
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 eliminates this – or does it?
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).
Famous Anterograde Amnesiac: HM • Severe epilepsy, treated with surgery to bilaterally remove medial temporal lobes, including hippocampus • Operation 9/1953, 27 years old
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 • Could learn to mirror reverse read and mirror trace
HM – Milner’s study (1962) 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
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
Squire’s model Representational Are true or false - verbalizable Temporal specification Expressed through performance rather than recollection
Conversion • Squire argues that these two are not clear-cut distinct systems • Remember Tulving’s semantic memory • Remember source amnesia! • Children • Confabulation • Dreams • Hypnosis
Amnesia and animals • declarative memory can gradually turn into non-declarative with repeated exposure • Animal models of the conversion • Plus shaped maze - rats learn to find food, which was always west • Started from the south – then were put into the north • First few trials – turned to west – impaired when lidocaine injected in hippocampus • Subsequent trials – turned to left (habit, not individual memory) – impaired when injected with lidocaine in the caudate nucleus
Human learning • Healthy and amnesiacs learn differently • Exposed to sentences such as „medicine caused hiccups” • Had to complement fragments (___ ____ hiccups) • Healthy • rapid learning • Semantic mistakes • Amnesiac • Slow learning • Faithful to original stimulus • In non-verbal tasks however (movements) trying to remember declaratively often impairs performance!
Competition of strategies • Squire – the two systems often compete to be the strategy of remembrance – as in healthy human habit learning tasks in fMRI • First medial temporal lobe activation • Many mistakes • Gradually the caudate nucleus takes over • More punctual • Movements/habits seem to be different from language
Species dependent strategies • Visual pattern discrimination learning • (+ vs ->) • Monkeys with medial temporal lesions learn the task – slowly • Amnesiacs seem to learn it very fast, then forget which answer is correct • For humans the task is too easy and likely to be taken over by the declarative system • More accurate would be trying to discriminate between paintings (original vs forgery) • This is the same argument as Dijk. Makes!
Modern interpretations • Two most popular are • Larry Squire – procedural – declarative • Later rephrased non-declaratie and declarative • Peter Graf, Daniel Schachter – implicit – explicit • They worked with healthy individuals and experimental settings
Explicit & Implicit Memory Tests Look at the following words. I will test your memory for these words in various ways.
Memory Test • Explicit test of memory: recall • Write down the words you remember from the list in the earlier slide
Memory Test • Explicit test of memory: recall • Write down the words you remember from the list in the earlier slide • Implicit test of memory: word fragments • On the next slide, you will see some words missing letters, some “word fragments” and some anagrams. Guess what each word might be.