1. Implicit Learning and Priming
Dr Magda Osman
Room 2.25
Office hours Mondays

2. Do you think you can be influenced to behave in ways without your conscious knowledge?
Yes No
Don’t know

3. Learning outcomes
Understand the different methods of examining priming (subliminal and supraliminal), and subjective/objective thresholds
Understand the different methods of examining implicit learning (SRT, AGL)
Understand the different theoretical positions proposed to account for evidence of implicit learning

4. Unconscious priming

5. Two types of priming techniques
Supraliminal: Presenting primes that are processed at a conscious level, that influence behaviour unconsciously
Subliminal: Presenting primes unconsciously, that in turn influence behaviour unconsciously

6. How can we know when a process is unconscious?
To show that unconscious processing occurs it is necessary to demonstrate a dissociation between a behavioural measure of performance and measures of awareness.
Two stages of information processing: encoding & retrieval:
Amnesics show difficulty in retrieving the details (declarative knowledge),
but that doesn’t mean to say they weren’t conscious at the time of learning (encode the experience – as procedural knowledge)
To demonstrate the encoding process as unconscious, you need to demonstrate that at the moment the stimulus was presented, the individual’s awareness of the stimulus was absent

7. How can we know when a process is unconscious?
Problems with definition of consciousness and detection threshold (at encoding)
Cheesman & Merikle (1984)
Subjective threshold – discriminative responding for which individuals CLAIM they are guessing, but are NOT responding at chance level
Objective threshold – discriminative responding for which individuals are ACTUALLY responding at chance level

8. Subliminal priming - what does it mean to learn without attention?
Presentation of stimuli subliminally – without conscious detection
Demonstrations of unconscious detection rests on two different points:
Accessibility of information at encoding (retrieval)
Availability of information stored after it was presented
Some say that unconscious detection = the inaccessibility of information at encoding (Brody, 1989) – but can you know?
Others say that unconscious detection = availability to consciousness is greater than accessibility (Erdelyi, 1986, 2004)

9. Subliminal priming
Market researcher James Vicary (1957) reported a study involving 700 cinema goers in the states.
The two messages shown during the film were “Eat Popcorn” and “Drink Coca-Cola”. A message was flashed for 3msc of a second every five seconds – in lab tests this was claimed to be too fast for conscious attention.
People Claimed this was too fast for conscious awareness.
Companies claimed that over a six-month period sales of popcorn rose 57% and sales of Coca-cola rose 18.1%.
This was the beginning of the concept of subliminal advertising.
However, these impressive results were never replicated, and in 1962 Vicary admitted the study was a hoax.

10. Subliminal priming/Masked Priming
stimuli too short (20-110ms with masking)/ or too low intensity to reach conscious level
But in both case processing of incoming stimuli is said to occur
Classic demonstrations
Semantic priming (Marcel’83)
Affective priming (Zajonc’80)

11. Simple Lexical Decision with subliminal priming
kurtka
Word
Non-word
TABLE
BREAD
PHOUD
BUTTER

12. Subliminal Priming Prime Mask Target TABLE XXXXXX PHOUD BREAD XXXXXX
BUTTER
HORSE
XXXXXX
BALLOON
20ms
20-200ms
1000ms

13. Masked Priming
Find that the masked stimulus (prime) influences the speed of judgment of word/non-word discrimination
Incongruent trials – slow responses
Congruent trials (semantically related trials) – speed responses
Congruent trials (semantically unrelated trials) – baseline
Opstal et al (2010) Opstal et al (2011)
TABLE
XXXXXX
PHOUD
BREAD
XXXXXX
BUTTER
HORSE
XXXXXX
BALLOON

14. Supraliminal Priming Bargh, Chen, & Burrows (1996) study
Priming Old Age and Walking to the Elevator
Primes were presented at a supraliminal level (conscious level)

15. Repetition Priming Jacoby et al (1989) Judgments of fame effect
Based on the effect reported by (Claparede (1911)
- Mere exposure to names of people will make them seem famous (people can’t figure out why the names are familiar so judge them as famous)
Jacoby et al’s (1989)
Exposure phase –non-famous names: Sebastian Weisdorf, Valerie Marsh, Adrian Marr either 1 or 4 times
Test phase –non-famous names & famous names – judgement of fame
Manipulation – test administered directly after exposure, or a day after.

16. Repetition Priming Jacoby et al’s predictions were:
Famous names – judged accurately,
New names – judged innacurately,
Old non-famous names [1x] more inaccuarte than [4x]
New names – judged more accurately compared to Old non-famous names [1x]
Old names [4x] judged inaccurately

17. What is the difference between subliminal and supraliminal primes?
They crucially differ according to their effects on behaviour
They crucially differ according to whether they are processed consciously
They crucially differ according to the content

18. Unconscious learning tasks

19. What is implicit learning?
e.g. of hidden „grammar rules”
Learning new skills in patients with amnesia
Automatic processing (fast, inflexible)
Implicit memory: memory without any sensation of remembering
Changes in performance (e.g. Word-stem completion task, anagram solution)
Performance of people with amnesia on indirect tests of memory

20. Arguments for implicit learning I
We sense that we can learn things intuitively – without effort
Language, is a good example in which we are able to acquire a lot of information very quickly – does this suggest implicit learning?
We can train animals to learn to do many things, they don’t seem to be conscious of what they know – they must be using a form of implicit learning, right?
Therefore, by extension if there are basic learning mechanism that animals have, then perhaps we have a basic unconscious systems as well?

21. Arguments for implicit learning II
We can apply knowledge without thinking
We are able to acquire complex information quickly – so, doesn’t this mean that we can learn implicitly?
There seem to be different types of learning, some which are harder to implement than others
Implicit and explicit learning refer to different states of consciousness, if these states exist, then surely there are different learning mechanism that generate them?

22. What does implicit learning imply?
Implicit is unconscious learning, that is, processes that operate independently of consciousness (Reber & Reber, 2001)
Knowledge that is stored in memory that cannot later be recalled or recognized, but can exert influence over behaviour
Implicit learning relies on knowledge and representations that are encoded and stored differently from explicit knowledge.
(Claparede (1911) – amnesic was pricked by concealed needle in their hand, days later they refused to shake the physician’s hand “You never know what people carry around”)

23. Newell & Shanks (2014)

24. Perceptual-motor/rule learning
Logic of Experiments
Present people with simple/complex stimuli that follow a rule
Include a training period
Include a test period
Explicit (or direct) measures of knowledge
Implicit (or indirect) measures of knowledge
Explicit measures:
Ask questions that directly relate to information that was presented during training
Ask people what they think they learnt
Implicit measures:
Ask people to report their confidence or how much they like the stimulus they are presented
Produce stimuli that don’t follow the pattern/rule that you were exposed to in training

25. Artificial Grammar Learning
Reber (1967)
Present people with stimuli that
follow a complex rule
Training period: MTTV
Try to remember as many of these strings of letters as possible
Test period: Which is grammatical?
VXM or VMR? BPPQ or BQF?
How did you decided which is grammatical
What is the grammar?

26. General findings
People show above chance accuracy (54%-69%) in discriminating between grammatical and non-grammatical letter strings. But are unable to report how they make their discriminations (Reber, 1967–replicated (Brooks, 1978; Dienes, Broadbent & Berry, 1991; Saffran, 2001),
People can transfer their ability to discriminate to letter strings they haven’t seen before, but without knowing. (Dienes & Altmann, 1997)
Cross modal transfer (from one sensory form to another)– people learnt letter string but at test were able to discriminate between sequences of musical tones (Altman, Dienes, & Goode, 1995)
If during training people are made aware that there is a grammar, their ability to later discriminate declines. (Reber, 1967; Reber, Kassin, Lewis, & Cantor, 1980)

27. But….
E.g. People may not learn rules, but just pairs of letters (bigrams) that the grammar allows. People trained on grammatical pairs were just as good as people trained with complete strings
(Dulany, Carlson, & Dewey, 1984; Perruchet & Pacteau, 1990; Shanks, 2004)
Grammaticality is conflated with familiarity, people only tend to rate grammatical strings if they feel that they are familiar to them. When looking at unfamiliar letter strings only, discrimination for grammaticality was at chance
(Kinder & Assmann, 2000; Johnstone & Shanks, 2001)
Familiarity – is a fluency effect (the easier something is to process, the more familiar it seems), when told to deliberately ignore the fluency of processing the letter strings, discrimination for grammaticality was at chance
(Kinder, Shanks, Cock, &Tunney, 2003)
Measures of explicit knowledge not exhaustive, and not inclusive
of what the individual may have actually learnt.

28. Serial Reaction Time Task
Nissen & Bullemer (1987)
Present people with stimuli that follow a rule. E.g. deterministic sequence:
Training period: Block of trials in which people perform the task
Test period:
Transfer task
Indirect Measures
Direct Measures

29. General findings
People show dissociation between the ability to perform the sequence and accuracy of their knowledge of the sequence (Hartman et al, 1989; Nissen & Bullemer, 1987; Willingham et al, 1989)
Learning through observation impairs performing the sequence, but not knowledge of the sequence (Kelly & Burton, 2001; Kelly et al, 2003)
Process dissociation in free generation tasks show that when people are told to explicitly avoid generating the sequence, they still generate the sequence (Cleeremans & Jiménez, 1998)
Dual Task studies show that you can learn the sequence even when having to complete a secondary task at the same time – like tone counting (Cohen et al, 1990; Frensch, Lin, & Buchner, 1998; Hsiao & Reber, 2001)

30. But…
Learning of the sequence is affected if you have to discriminate between high and low tones and indicate the result using foot-tapping, or a highly visual demanding task.
(Heuer & Schmidtke, 1996; Rowland & Shanks, 2004)
Poor discrimination between old and new sequences was improved from guessing to well above chance, by introducing performance related pay to motivate individuals to respond accurately.
(Johnstone & Shanks, 1999)
Usually, only partial elements (6-items) of the sequence are presented for later recognition tests, when trained for a long time, and then presented whole (12-items) old or new strings people were faster to respond to old than new, and were able to discriminate old items from new
(Shanks & Johnstone, 1999; Shanks & Perruchet, 2003)

31. Theoretical Question Given that there are so many different forms of
knowledge:
Are there multiple types of learning processes/mechanisms
Is there one single learning process/mechanism

32. Implicit learning = rule abstraction
Learning is a sophisticated process that tracks and exacts patterns and forms them into rule without any conscious effort
As a result, what becomes processed are the deep underlying structures (e.g. language learning, intuitive reasoning)
From this we can make accurate predictions and generalize and transfer knowledge (e.g. cross modal transfer)
We do not need to consciously attend to information for it to be learnt.

33. Implicit learning = exemplar based
Given that we don’t always know what to expect in our environment,
we often begin by learning by example,
when we have enough examples that are stored in memory,
we can begin to make predictions by comparing how similar new examples are to the ones we have in memory.
We do not need to attend to information to learn it implicitly

34. There is no implicit learning
TAP – transfer appropriate processing
(Morris et al, 1977) – learning the properties of the words (semantic or phonemic), when tested based on either properties, when training & test matched, performance was better.
Our cognitive system is designed to find short cuts. We often begin by learning chunks of information, which makes it easier to store information in memory
From this simple rules can be formed which enable us to make predictions.
Attention is absolutely necessary for learning
(Shanks & St John, 1994; Shanks, 2004)

35. To what extent are you convinced that there is evidence of implicit learning?
I am entirely convinced
I am somewhat convinced
I am not sure
I am somewhat unconvinced
I am entirely unconvinced

36. Describe and evaluate the different methodological approaches used to investigate implicit learning