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
Budapest Semester in Cognitive Science
Try to remember these!
Now look carefully at these pictures. You will need to recall them later.
How many stripes did you see on the cat?
G V U
L S J
N A Z
A M K
X F Q
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Wilson Bryan Key: Subliminal Seduction and Media Sexploitation
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.
LONG TERM MEMORY
(skills & habits)
(classical & operant conditioning)
Medial Temporal Lobe
past experiences influence perceptions, thoughts & actions without awareness that any information from past is accessed
conscious access to info from the past
(“I remember that..” )
-> involves conscious recollection
Look at the following words. I will test your memory for these words in various ways.
Subjects presented with target words.
Subsequent recognition phase: Targets and distractors.
Right answers measured:
Fragment Completion A--a--in
Word Stem Completion Bri---
Implicit memory is evidenced when Ss complete or identify more studied than non-studied words.
Reaction-time measured (does not exclude correctness)
Degraded Word Naming
Implicit memory evidenced by faster RTs for studied words
ch _ _ _ _
Graf et al. (1984).
Graf, Squire & Mandler, (1984)
Presented amnesic patients and controls with word lists - S’s made pleasantness ratings.
Test stimuli for Cued Recall and Stem Completion identical -
only instructions differed.
Forgetting: Tulving et al (1982):
S’s learn list of uncommon words (e.g. Toboggan).
Test = standard recognition, fragment completion (_O_O_GA_)
Repetition priming effect equal for recognised and non recognised words
Fragment completion performance unchanged after 1w
DID: Dissociative Identity Disorder (DSM-IV)
Coma, vegetative state and locked-in syndrome
based on: Zoltán Dienes Conscious and unconscious mental processes
People learn to make decisions on a task more accurately or more quickly without being able to justify their decisions adequately.
The learning process by which people come to acquire implicit (unconscious) knowledge.
Acquisition of natural language, social skills, musical appreciation, many practical skills
Subjects “trained” on grammatical sequences, then presented with grammatical vs non-grammatical sequences.
Group A: Learn “grammatical” letter sequences
Group B: Learn random letter sequences (using same letters)
Both groups then shown 44 letter sequences, 22 of which were gramatical, 22 of which were random.
Group A successfully categorised 79% of the sequences
Group B were at chance
Effect lasts for years (Allen & Reber, 1980)
When questioned about the nature of the grammar, subjects generally claim to be guessing and are unable to report any knowledge of the rules
Many replications (but effects tend to be smaller)
Those who learned bigrams or trigrams performed as well as those who learned the entire strings
Grammaticality has no effect at all? Is it all conscious memory then?
The most direct way of testing for conscious knowledge is to test for higher order thoughts(Dienes, Altmann, Kwan, & Goode 1995)
When there was an implicit basis: No effect of learning condition nor secondary task on percentage correct
When there was an explicit basis: A secondary task disrupted correct classification in the rule search condition
Subjects interact with a simulated system, e.g. the sugar production factory (Berry & Broadbent 1984)
On each trial, hire and fire workers to try to maintain the level of sugar production at a target value.
Underlying equation (unknown to subjects) links current sugar production to number of workers and past sugar production.
High predictability (75%)
low predictability (58%) cards
(1) One-Cue Learning.
Basing responses on the presence or absence of a single card (e.g., "I predicted rain whenever I saw the triangle card.").
(2) Multi-Cue Learning.
Basing responses on the combinations of cues present on a given trial (e.g., "I noticed that triangles and diamonds usually meant rain, and the circles and squares meant sunny."5).
(3) Singleton Learning.
Learning the correct response to singleton patterns (A = 0001, B = 0010, C = 0100, D = 1000), in which only a single card appears, and guessing on the remaining trials (e.g., Memorizing the single cards, "The single cards were the easiest, so I concentrated on those.").
(Nissen & Bullemer, 1987)
On each trial a light goes on
Just press corresponding button
Unbeknownst to subject, sequence of lights is rule governed
Subjects are sensitive to the presence of the sequence even when they deny knowing that there was a sequence