CogPsychLecture_Expertise

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Cognitive Psychology
Expertise
22nd October 2008
James Matthews
Expertise
Today’s Lecture
• What is expertise & expert performance
• Traditional View of Expertise
– Prodigies & Savants
– Talent as a predictor of success
• Expert Performance
• Research Techniques
• Theories of Expertise
–
–
–
–
Recognition Association Theory
Template Theory
ACT Theory
Ericsson’s Deliberate Practice
What is expertise?
• Innate Talent / Hard Wired?
• Acquired / Software?
What is expertise?
• Expertise
– refers to the mechanisms underlying the
superior achievement of an expert, i.e. one
who has acquired special skill in or knowledge
of a particular subject through professional
training and practical experience.
(Webster’s dictionary)
Who is an expert?
• An expert can be defined as any person
who is wearing a suit, carrying a laptop
computer and more than 50km from
home !
• An expert is a person who possess
specialist knowledge in a designated field
(e.g. medical pathology). (Moran, 2004)
Perceived Vs Consistent Expert
Performance
• Criteria for expert performance varies from domain
to domain, e.g. chess and the arts.
• Outlier – if a person is performing at least 2 standard
deviations above the mean level in the population,
that individual can be said to performing at an expert
level (Ericsson & Charness, 1994).
• The distinction between perceived and actual
expertise is important as performance of people
nominated as experts is not always measurably
superior.
Perceived Vs Consistent Expert
Performance
• Numerous studies show that financial stock experts investments
yield returns that are not consistently better than the average of the
stock market
• Experts may have more knowledge but their performance on key
tasks is not always reliably better.
• We must not assume experts performance is superior, they must
demonstrate it is.
Traditional View of Expertise
• “On the whole the gods do not bestow more than
one gift on a person” (Murray, 1989)
• Bias towards attributing high abilities to gifts
rather than experience.
• Galton – first person to investigate expertise
– Innate ability
– Motivation
– Effort
Traditional View of Expertise
• Gardner (1983) – Proposed 7 types of intelligence
– Linguistic, Musical, Spatial, Mathematical, Kinaesthetic, Interpersonal
and Intrapersonal
• Gardner's theory argues that intelligence, as it is traditionally
defined, does not adequately encompass the wide variety of abilities
humans display
• He believed the salient aspect of innate talent was the potential for
achievement and the capacity to learn material relevant to one of the
intelligences
• Ideas based on the research of savants and prodigies
Performance of Prodigies &
Savants
Prodigy: person, especially a young
one, who displays unusual or
exceptional talent or intelligence (APA
Dictionary, 2009)
Savant: Individuals with a low level of
general intellectual functioning who
are able to perform at high levels in
some special tasks (Ericsson &
Charness, 1994)
Performance of Prodigies &
Savants
• Talent in Music – Absolute Pitch
– 0.01% of population
– 1st appears in early childhood
– Adults appear unable to attain in spite of training
• Hulse (1993) – AP can be acquired by anyone, but only
during a limited period of development.
– Indivs with AP started music instruction before age of 6
– Studies have shown successful results in teaching AP to 3 – 6
year old children
• AP a natural consequence of the right instruction and
access to opportunities to play with an instrument.
Performance of Prodigies &
Savants
• Acquisition of skills by prodigies follows the same
sequence of stages as other individuals in the same
domain BUT attain higher levels quicker and faster.
• Most Child Prodigies never attain exceptional levels of
performance as adults.
• Most exceptional adult performers started instruction
early and developed due to high levels of appropriate
training (Bloom, 1985).
• The role of early instruction and maximal parental
support appears to be more important than innate talent.
Performance of Prodigies &
Savants
• Savants - some parents have believed these gifts as
coming from God.
• Lab studies of performance of savants have shown them
to reflect acquired skills.
– Naming the day of the week of a certain date is replicatable by a
college student after a months training.
• One ability that does not seem to be reproducable after a
period of training concerns some savants’ ability to play
a piece of music after a single hearing.
Performance of Prodigies &
Savants
• Sloboda et al (1985)
– Savant able to memorise a new piece of music
– Marked difference in success with a conventional vs tonally
unconventional piece.
– Thus savants may need access to stored patterns and retrieval
systems
– Many savants are blind so cannot read music so learn by
listening which provides motivation for development of certain
memory skills
• Laboratory research on prodigies and savant provides
no conclusive evidence for innate talent.
Talent as a predictor of future
success
• Hardware
– Basic elements that cannot be changed through training
• Software
– Knowledge and strategies that can be readily changed as a
function of training and learning
• Hardware – Intuitively appealing
BUT
– Faster reflexes/extreme visual acuity
– Age of peak level of performance
BUT
– Fast twitch Vs Slow twitch fibres
– Rift Valley - Kenya
Talent as a predictor of future
success
• Colin Jackson - “The Making of Me”
Former World Champion & World Record Holder, 110m Hurdles
• A sample of his leg muscle showed that he had 10% super fast
twitch fibres, when all previous athletes tested had only 2%.
• Family support was also thought to have been highly significant.
• Clip showed a stadium in Jamaica with 30000 people cheering on
children taking part in an average school sports meet.
Talent as a predictor of future
success
• Ericsson et al (1993)
– Elite athletes show faster reaction times to
situations within their own domains than
novices or non expert
– No difference between experts and novices
on reaction times for simple lab tasks
• This finding is replicated across numerous
domain, e.g. chess
Talent as a predictor of future
success
• Physiological and Anatomical attributes can
change dramatically in response to physical
training
Percy Montgomery, World Cup Winner, SA
• Height is the one exception…
– UK Sports search for tall people for 2012
Talent as a predictor of future
success
• Overall little empirical evidence supports
the talent view of expertise and expert
performance.
Expert Performance
• Remember financial example…
– We must not assume experts performance is superior, they must
demonstrate it is.
• Key challenge is to identify particular well-defined tasks
that frequently occur and that capture the essence of
expert performance in a specific domain.
• De Goot – pioneering research to capture expert
performance
De Goot’s Research
• De Goot – Chess Master
• Determined that the ability to play chess is best captured
in the task of selecting the next move for a given chess
position taken from the middle of a game between two
chess masters.
• Presented chessboard configurations to chess playing
subjections for periods of 2 – 15 seconds.
• Found that experts were superior to other players in
ability to reproduce accurately the location of pieces.
De Goot’s Research
Chase and Simon
• Chase and Simon (1973) replicated De Goot’s
findings and discovered something new:
• The superior STM performance of chess experts
was confined to meaningful (i.e. game specific)
chess patterns
• It did not appear when unstructured “scrambled”
or random patterns were presented
Chase and Simon
Theories of Expertise
• Suggested that the better performance of
experts is not due to any general memory
advantage (such as photographic memory)
• Instead they proposed that experts superior
STM performance was due to their ability to
recognise configurations of their chess pieces
on the basis of their knowledge of vast numbers
of chess patterns (e.g. 50,000 – 100,000)
Recognition – Association Theory
• Became known as the “Recognition – Association” theory
• A chess position is perceived by a skilled player in terms of groups
of 2 – 3 chess pieces corresponding to familiar patterns (chunks) in
LTM
• With extensive experience and learning, the size and number of
chunks in LTM can increase.
• Each of these chunks is thought to be associated with plausible
moves
• Therefore experts superior memory for chess patterns attributed to
their ability to perceive the board in terms of chunks and to hold
labels in corresponding to each chunk in working memory.
Research Methods in Expertise
• In-depth Interviews:
– May lead to grounded theory, where researchers build a
conceptual model inductively from data yielded from participants
rather than deductively
• Think aloud verbal protocols:
– Required to talk about or give running commentary on their
thoughts and actions as they tackle a problem
– Some limitations:
• Editing problem from sheer volume of data
• Protocols limited to consciously attributable processes
• People more self conscious / guarded?
Research Methods in Expertise
• Thought Sampling:
– Involves equipping athletes with electronic bleepers during domain
relevant situations and cueing them to randomly pay attention to their
thoughts at that time
– Good ecological validity
• Pattern recall and recognition tasks:
– De Goot and Chase and Simon’s work
• Eye – tracker technology:
– Saccadic Movements – high speed jumps
– Smooth Pursuit Movements – help focus on a given target
– Research supports that experts display a more efficient visual search
strategy than less skilled counterparts
– Cricket research (Land and McLeod, 2000)
Back to theories of expertise
• It is wrong to assume that the only
characteristic of expertise is superior
memory
• Holding & Reynolds (1982) argue that
experts also possess superior strategic
processing skills to novices
Theories of Expertise
Template theory
• Experts organise chunks into meaningful
complex structures known as templates
• Chess pieces might be remembered as being in
a strong, weak or neutral position as a whole
• Templates can hold larger amounts of
information than simple chunks
• Thinking can be directed strategically
Template Theory
Charnes et al. (2001) presented chess boards to
experts and novices
Eye movements were recorded for the first second
after presentation
Even in this short time experts were more likely
than novices to fixate on tactically relevant
pieces (80% v 64%)
Global structures of game patterns seem to be
stored by experts
Template Theory
• McGregor & Holmes (2002) showed chess boards to
experts and novices
• Participants had to indicate if they had seen a particular
board before or not
• Experts were better at realising that they had not seen a
particular board if 1 important piece was shifted rather
than if the whole board was translated one space over.
• Evidence that the way the game is developing, and
associated strategies are all coming into play
Template Theory
• Evaluation:
• It is not clear from template theory what
the precise information is that is being
stored.
• Attack / defense relations are more
memorable than piece location, but this
does not help in deciphering what the
contents of memory are…
Andersons ACT Theory
• Adaptive Control of Thought theory proposes 3
connected systems at work in experts:
• Declarative memory (semantic network)
• Procedural memory (simplifying decision
making)
• Working memory
Andersons ACT Theory
• As a novice becomes more expert. . .
• There is knowledge compilation, resulting in a shift
from declarative to procedural memory
• Proceduralisation is where production rules (if…. then)
are drawn up to make decisions and take action more
quickly
• Composition improves performance by reducing a
repeated sequence of actions to a single action
Andersons ACT Theory
• Zbrodoff (1995) had participants answer questions about
the alphabet
• e.g. S + 4 = ?
Ans: W
• Initially participants were quicker to answer S + 2 than S
+4
• This is because initially participants were running
through the alphabet in their head
• After practice the times became equal as participants
began to rely automatically on past experience
Andersons ACT Theory
• Evaluation:
• There is good evidence of a shift from
declarative to procedural memory as people
become well practiced at a particular task
• This model deals well with unvarying
procedures (touch typing), but does not say
much about creative/adaptive expertise (like that
seen in scientific theory)
Ericsson’s Theory of Deliberate
Practice
• Ericsson believed that practice of the right sort
was not only necessary but also sufficient for
memory expertise to develop
• A wide range of expertise can be developed
through deliberate practice, which has 4
aspects:
– The task is at an appropriate level of difficulty
– The learner is provided with informative feedback re
their performance
– The learner has sufficient opportunities for repetition
– It is possible for the learner to correct his / her errors
Ericsson’s Theory of Deliberate
Practice
• What is controversial is Ericsson’s belief that innate talent has no
influence on expert performance.
• It is only for height that innate characteristics have been shown to
matter (Remember London 2012)
• Evidence of this position:
• Ericsson and Chase (1982) - Digit Span Task
– Extensive practice on task where numbers had to be recalled
immediately
– 7 digits recalled on average at start
– 80 digits recalled after practice for an hour a day for 2 years
– No cross over to letter or word spans
– Increased his span by organising chunks into a hierarchial retrieval
structure
Ericsson’s Theory of Deliberate
Practice
• According to Ericsson and Lehman (1996), what’s important is the
amount of deliberate practice as compared to the amount of sheer
practice
• Think of kids who spend hours on the road kicking a football but
never make professional or representative level
• Ericsson et al (1993) – Violinists at German music academy
– Key difference between violinists of varying ability was the amount of
deliberate practice
– 7,500 hours engaged in deliberate practice for Experts Violinists
– 5,300 hours engaged in deliberate practice for Good Violinists
– Perfecting their skills as compared to mindlessly repeating elementary
drills
Ericsson’s Theory of Deliberate
Practice
• Is innate ability or intelligence unimportant in the development of
expertise?
• Ceci and Liker (1986) – Harness Racing Study
– 14 experts and 16 non experts,
– IQs’ varied between 80 and 130 in both groups
– Performance indicated that experts performed better than non experts
regardess of IQ level
• Ceci and Liker (1986) suggested “that IQ is unrelated to real world
forms of cognitive complexity that would appear to conform to some
of those that scientists regard as hallmarks of intelligence behaviour”
Ericsson’s Theory of Deliberate
Practice
• Evaluation:
• Evidence indicates that deliberate practice is necessary
for expertise BUT the support that it is sufficient for
expertise is somewhat less consistent
Ericsson’s Theory of Deliberate
Practice
• Some Limitations:
• Lots of evidence that DP is not the only factor. Innate
ability predicts long term career success in many
occupations (Gottfredson, 1997)
• The notion that innate talent is irrelevant seems
implausible (Sternberg, 2001)
• It’s the highly intelligent or talented individuals who are
willing to put in the hours of practice
– Motivation…
Ericsson’s Theory of Deliberate
Practice
• Some Limitations:
• If nearly all experts in the field have enormous talent,
then it is not surprising that individual differences in
talent do not predict expertise (e.g. height in basketball
which does not predict performance)
Expertise
Today’s Lecture
• What is expertise & expert performance
• Traditional View of Expertise
– Prodigies & Savants
– Talent as a predictor of success
• Expert Performance
• Research Techniques
• Theories of Expertise
–
–
–
–
Recognition Association Theory
Template Theory
ACT Theory
Ericsson’s Deliberate Practice
Readings
• Eysenck & Keane: Chapter 13
• Ericsson, K.A & Charness, N. (1994). Expert
Performance – Its Structural and Acquisition.
American Psychologist, 8, 725 – 747.
• Moran, A.P (2004). Sport & Exercise
Psychology. A Critical Introduction.
• Matlin: Chapter 10
Articles to Read
• Miller, L.K. (1998)The Savant Syndrome:
Intellectual Impairment and Exceptional Skill.
Psychological Bulletin, 125, 31-45.
• Helsen, W.F., Hodges, N.J., Van Winckel, J. &
Starkes, J.L. (2000). The roles of talent, physical
precocity and practice in the development of
soccer expertise. Journal of Sports Sciences,
18, 727 – 736.
Extinction
• Marzi et al. (2001). What exactly is extinguished
in unilateral extinction? Neurophysiological
evidence. Neuropsychologia, 1354 – 1366.
• Rees et al. (2000). Unconscious activation of the
visual cortex in the damaged right hemipshere of
a parietal patient with extinction. Brain, 1624 –
1633.
• Both introductions give good basic
explanations.
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