QUOTES IX
Quotations about
THE BASES OF INTELLIGENCE
Are there any identifiable psychological or physiological
bases for human individual differences in measured intelligence?
Despite the passing of some eighty summers since the invention
of IQ tests, and despite ceaseless calls for psychology to 'go
beyond' IQ to identify 'what the tests test', there is
still little consensus in and around cognitive and differential
psychology as to the nature and bases of intelligence itself.
Intelligence has stimulated many attempts to specify its essence-e.g.
'learning ability', 'abstract reasoning ability', 'information
processing ability' or just 'the capacity to adapt'; but no one
such approach has caught on.
Hardened psychology-watchers will say there is nothing new in
this. For psychologists have established no certain research method
for proceeding to undertake such fundamental psychological
analysis of any human ability or propensity. On the
one hand there is macroscopic 'behaviour' (including test
performances) that is too big and itself requires explanation
in terms of its 'bases'; on the other hand there are (presumably,
somewhere) the much-sought-after microscopic processes
of low-level neuropsychology and computational cognitivism. What
is hard is to find with any scientific authority is a level
in between-a level at which talk of operating
characteristics, goals and strategies (cf. abilities, desires
and intentions) seems natural.
It is pretty easy to see what sort of research to do if it is
desired to 'measure' an ability, to discover a treatment for a
neurotic condition, or to enquire to what degree genetic and/or
environmental factors furnish the developmental 'origins' of human
psychological differences. Such psychometric, psychotherapeutic
and psychogenetic questions present themselves together
with straightforward methods relevant to answering them: count
and correlate; experiment and observe; follow twins and adoptees.
It is precisely psychology that is hard to do convincingly.
This difficulty may arise because 'folk psychology' already does
quite a lot of the job so well (see Quotes VII).) Some may thus
think it no shame to be uncertain about 'what intelligence
really is'. Moreover, psychologists also draw a blank about what
underpins or provides any basis for extraversion, authoritarianism,
self-monitoring, sexual orientation and other important characteristics
that are perfectly 'measurable' (given a little co-operation).
Still, intelligence differences are arguably rather special amongst
human psychological differences in being especially readily and
reliably measured {see Quotes VIII}, in having had their origins
very fully researched {see Quotes X}, in being demonstrably important
{see Quotes XI} and in having understandably excited the interest
of 'cognitive' and developmental psychologists {see Quotes XII
and XIII}. To that extent, continuing uncertainty about its essential
nature must remain something of a puzzle.
In part, the problem is that psychological fashions of explanation
have changed repeatedly because of doubts as to the adequacy of
any of them. Explanations invoking brain bumps, innate proclivities,
types of conditioning, 'black boxes', neurotransmitters and 'interaction
effects' have all worn thin. In addition, sustained application
to explaining differences is hard to find within any
of psychology's major explanatory paradigms or schools of thought.
Nevertheless, in recent years (beginning with Hans Eysenck's classic
theoretical paper about IQ and reaction time (1967, Brit.J.Educ.Psychol.))
increasing effort has been made to trace IQ differences to underlying
differences in 'basic information processing abilities'. (More
strictly, the effort relates to g differences, for g
increases through childhood as well as distinguishing between
children and between adults of the same chronological age-see
Quotes VIII, X.) In particular, g has been linked to 'mental
speed' of various kinds:
1) to overall speed of reaction to stimuli (RT);
2) to speed of choice- or decision-making (DT-which is choice
RT minus the 'motor' component of how long it takes a subject
to respond to the onset of a simple stimulus that does not require
any choice to be made); and
3) to speed of intake of elementary perceptual information (especially
'inspection time' (IT)).
Broadly, the idea of Hans Eysenck, Arthur Jensen, Mike Anderson,
Ian Deary, Con Stough and much of the rest of the 'London School'
of psychology has been:
(i) that such speed differences are probably central to individual
differences in 'fluid intelligence' (gf, the ability to
solve new problems); and
(ii) that these differences in speed (and/or fidelity)
of elementary information processing express themselves gradually,
over the course of development, into further differences between
people in 'crystallized general intelligence' (gc, knowledge
and skills).
[Normally gf and gc correlate substantially, but
gf declines in the average person from perhaps age 27 onwards
(and markedly after age 55), while gc 'holds' relatively
well-see Quotes XXI.]
Confronting such 'simplistic' theorizing about intelligence is
a wide range of experts in subjects outwith differential psychology.
Some are social environmentalists who balk at any story of g
that lends itself to postulating substantial genetic origins for
g differences. Other objectors are cultural relativists
who suppose that cross-cultural comparisons in intelligence are
odious and impossible because cultures are so different-thus intelligence
can necessarily have no 'basis' in anything so cross-culturally
measurable as 'mental speed' or performance on 'elementary cognitive
tasks'. Some objectors are developmental psychologists who think
of intelligence as a multi-faceted 'construction'-more like gc
than gf (see Quotes XII). Still others are cognitive psychologists
who liken the human mind to a computer, study memory and language
in psychology students, decline to insist on reliable tests for
use with the general population, and thus claim that they alone
are pursuing the question of what intelligence really is (see
Quotes XIII).
*********************************************************************
For more coverage of the psychology of intelligence,
and in particular of 'inspection time', see:
BRAND, C.R. (1996). The g Factor.
Chichester : Wiley DePublisher.
[The book was first issued, in March, but then withdrawn by the
'publisher' because it was deemed to have infringed modern canons
of
'political correctness.']
For a Summary of the book, Newsletters concerning the
de-publication affair, and others' comments
and reviews, see the Internet URL sites:
http://laboratory.psy.ed.ac.uk/DOCS/crb/internet.html
http://www.webcom.com/zurcher/thegfactor/index.html
For Chris Brand's 'Get Real About Race!'-his popular exposition
of his views on race and education in the Black
hip-hop music magazine 'downlow' (Autumn, 1996)-see:
http://www.bhs.mq.edu.au/~tbates/intelligence/Brand_downlow.html
*******************************************************************
INDEX to QUOTES IX.
Page
(i) The problem of finding a research-based or scientific
answer to the question 'What is intelligence?'
5
(ii) Some answers. - g is not alone!
7
(iii) Is intelligence (whether operationalized as IQ, Mental
Age or g) associated with faster reaction times
(RTs)? 10
(iv) Is g associated not so much with 'output'
as with 'intake' speed? 15
(v) What progress, if any, has been made towards linking
intelligence differences to physical parameters
- and especially to central nervous system structure and
function? 22
(vi) Might 'cognitive psychology' provide the answer?
28
Epilogue
(i) The problem
"Three or four years ago we tested fifty members of the American
Association for the Advancement of Science with the ordinary laboratory
tests in sense discrimination, memory, accuracy of movements and
the like. They did not do as well as ordinary college students.
....As I understand you now, your view is that if we got an accurate
measure of the common element in all varieties of sense discrimination,
it would correlate perfectly with intelligence, the fact being
that the different varieties of sensory activity agree together
only in a general core or kernel of intellect itself. If this
were the case, I should interpret it as follows: that in measuring
any sensory activity we measured a complex of the mere sensory
capacity and of the capacity to understand instructions, to be
attentive and ambitious, and to use all the clues that might be
available in making the sensory judgments."
E.L.THORNDIKE, 1904, letter to Charles Spearman, published in
R.B.Joynson, The Burt Affair. London : Routledge, 1989.
"[I have not meant to say] that general intelligence was
based on sensory discrimination, if anything vice versa.
I take both the sensory discrimination and the manifestations
leading a teacher to impute general intelligence to be based on
some deeper fundamental cause."
C.SPEARMAN, circa 1908, quoted by C.Burt, 1909-10,
British Journal of Psychology 3.
"Observationally, one can say little more about intelligence
than that it is what the tests test."
Helen PEAK & Edwin BORING, 1926.
"Since the beginning of the present century, a somewhat heated,
and not a little confusing, controversy has been going on among
psychologists regarding the nature of intelligence."
M.COLLINS & J.DREVER, 1936.
"Psychology now seems to find itself in the paradoxical position
of devising and advocating tests for measuring intelligence, and
then disclaiming responsibility for them by asserting that "nobody
knows what the word really means"."
D.WECHSLER, 1958.
"The short answer to the question, 'What is intelligence?'
is that we are just not sure."
D.W.PYLE, 1979.
"Experimental psychologists, who claim to study the human
mind, have been strangely loath to tangle with the concept of
intelligence." N.J.MACKINTOSH, 1981.
"We may be able to measure intelligence, but we don't know
what it really is."
H.GLEITMAN, 1981.
"We have no really adequate theory of intelligence."
E.J.PHARES, 1984.
"....there has never been a measure that has been so ardently
endorsed and widely validated and yet so pervasively controversial
as IQ."
S.CECI, 1991, Developmental Psychology.
"Nothing in The Bell Curve angered me more than the
authors' failure to supply any justification for their central
claim, the sine qua non of their entire argument, that
the number known as "g", the celebrated general factor
of intelligence....captures a real property in the head."
S.J.GOULD, 1994, 'Curveball.' The New Yorker, 28 xi, p.143.
(ii) Some answers
"[Herbert Spencer's (e.g. 1855, The Principles of
Psychology) view of the ontogeny, or individual development,
of intelligence in humans, from birth to maturity, is that it
has three main aspects: (a) an increase in the accuracy of inner
adjustments to outer demands, (b) an increase in the number of
items of simple knowledge, and (c) an increase in the number of
items of consciousness of the external environment. The idea of
accuracy of perceptions was likely a precursor of Francis Galton's
(1912-1911) emphasis on sensory discrimination as a measure of
intelligence...."
A.R.JENSEN, 1987, In J.A.Glover & R.R.Ronning, Historical
Foundations of Educational Psychology. New York : Plenum.
"Geniuses are commonly believed to excel other men in their
power of sustained attention. - But it is their genius making
them attentive, not their attention making geniuses of them."
William JAMES, 1890.
"What we call intelligence in the narrow sense of the term
consists of two chief processes: first, to perceive the external
world, and then to re-instate the perceptions in memory, to rework
them and to think about them."
Alfred BINET, 1890.
"The present results support the hypothesis....that the efficiency
of a man's equipment for the specifically human task of managing
ideas is only loosely correlated with the efficiency of the simpler
sensori-motor apparatus which he possesses in common with other
species." E.L.THORNDIKE, W.LAY & P.R.DEAN, 1909,
American Journal of Psychology 20.
"[Intelligence-test scores] tell us the extent to which a
person has become familiar with the vocabulary, the preferred
thinking styles, and the current intellectual problems of western,
middle-class society."
Jerome KAGAN, 1975.
"I regard the attempt to identify the "essence"
of a g factor as hopeless."
J.B.CARROLL, 1976.
"....the search for a 'true', single information-processing
function underlying intelligence is likely to be as successful
as the search for the Holy Grail."
Earl HUNT, 1980, British Journal of Psychology 71.
"Mental testing is in fact a subject devoid of scientific
interest."
N.S.SUTHERLAND, 1980.
"....regarding IQ tests as measures of 'intelligence' is
nonsensical. ....The Jensen data on reaction times seem to me
inherently implausible."
L.J.KAMIN, 1981.
"I did not expect impressive correlations of latency parameters
from very simple tasks with global or factor scores from very
complex [IQ] tests, and the correlations have not, in fact, been
impressive. They have generally been at the same meagre level
- roughly from .20 to .40 - as the so-called "personality
coefficients"(Mischel, 1968) that have plagued the literature
on relationships between personality tests that supposedly measure
the same or similar things."
R.J.STERNBERG, 1981, Journal of Educational Psychology.
"Many a researcher has wasted his life in pursuit of a "speed"
measure of intelligence."
J.P.DAS et al., 1981, in M.Friedman, J.P.Das & N.O'Connor,
Intelligence and Learning. New York : Plenum.
"Correlations between psychometric measures of ability and
information-processing operations have hovered around .30."
L.A.COOPER & D.T.REGAN, 1982, in R.J.Sternberg, Handbook
of
Human Intelligence. Cambridge University Press.
"If we ignore "g" and its relatives, I think they
will go away."
D.K.DETTERMAN, 1982, Intelligence 6.
"Just a few years ago, students were being taught that measures
of basic processes did not correlate with intelligence.... ....there
can now be little doubt that basic cognitive tasks do correlate
substantially with more traditional measures of intelligence."
D.K.DETTERMAN, 1984, Contemporary Psychology.
"Intelligence is mental self-government. ....Intelligence
must legislate, execute and evaluate. ....My own triarchic theory
would probably best be characterised as a modified, federated
oligarchy."
R.J.STERNBERG, 1986, in R.J.Sternberg & D.K.Detterman,
What is Intelligence? Norwood, New Jersey : Ablex.
"Analytically, intelligence appears to be a metaphor of heterogeneous
capacities, abilities and performance (i.e. problem-solving, language
and learning ability, mental states or others), rather than something
per se."
A.FASOLO & G.MALACARNE, 1986. Paper read to the NATO Conference
on the Evolutionary Biology of Intelligence, Poppi, Italy.
"Intelligence is not an entity within the organism, but a
quality of behaviour. ....Within the human species, intelligence
comprises that combination of cognitive skills and knowledge demanded,
fostered and rewarded by the particular culture within which the
individual becomes socialized."
Anne ANASTASI, 1986, in R.J.Sternberg & D.K.Detterman,
What is Intelligence? Norwood, New Jersey : Ablex.
g is not alone!
"There is no single theory of heat, but two rather different
theories, the thermodynamic and the kinetic.... There is no unified
theory of heat, and ultimately heat is defined in terms of the
measuring instruments used - very much as intelligence is....
Furthermore, different ways of measuring temperature do not give
the same results.... The measurement of intelligence is beset
with the same problems and difficulties as the measurement of
heat or any other physical quality."
H.J.EYSENCK, 1981.
"No-one has yet been able to say what electricity is."
H.C.FUNK, 1982, Milton Weekly Tribune.
"What is light? What is matter? ....a recently completed
experiment goes so far as to indicate that these questions might
have no answers at all."
R.STANNARD, 1983.
"We are frequently warned of the danger of reifying g,
but it is never made very clear just what this might mean. Is
there a danger of reifying the physicist's concept of energy,
which is also an abstract theoretical construct? One and the
same energy is assumed to be manifested in various forms, such
as "kinetic", "chemical" and "potential"
energy. Is the physicist guilty of reification when the concept
of gravitation enters into his explanation of certain physical
events? For nearly a century the gene was a hypothetical construct,
quantitative genetics and population genetics ere developed entirely
in terms of this construct."
A.R.JENSEN, 1985, at Buros-Nebraska Symposium on Testing.
"....intelligence is observable. It is not a capacity. Height
measures taken during the period of physical development are not
interpreted as a fixed capacity for growing in stature."
L.G.HUMPHREYS, 1985, in B.Wolman, A Handbook of Intelligence.
New York : Wiley DePublisher .
"Gould denies the reality of g on the grounds that
g isn't literally a thing in the brain, but this argument
confuses reality with thinghood. Solubility, after all, is an
empirically real property of sugar cubes although it is not a
"thing" spatially inside them.... We now identify solubility
with a certain arrangement of atoms, but we have little idea of
the arrangements of neurons with which intelligence is to be identified.
This no more shows a weakness in our present idea of intelligence
than ignorance of atomic theory centuries ago implied weakness
in the then current idea of solubility."
M.LEVIN, 1990, Journal of Social, Political and Economic Studies
15.
(iii) Is intelligence speed of reaction?
"If intelligence is conceived of as speed of information
processing, then simple reaction time [recognizing the arrival
of one particular stimulus], involving zero bits of information,
should not correlate with intelligence, but the slope of the regression
line, showing increase of reaction time with amount of information
processed, should correlate (negatively) with intelligence...
Experimentally, the prediction has been tested.... Reaction time
experiments, properly interpreted, do not appear to contradict
a theory of intellectual functioning based on the notion of mental
speed."
H.J.EYSENCK, 1967, British Journal of Educational Psychology
37.
"University students show faster reaction time (RT) than
vocational college students, who are in turn faster than unskilled
factory workers, who are faster than the mentally retarded....
It already appears that something approaching half the total variance
in g can be accounted for purely in terms of individual
differences in RT (and in its associated intra-individual variability)
to a few elementary cognitive tasks."
A.R.JENSEN, 1984, Behavioral & Brain Sciences 7.
"The sensitivity of simple oculomotor Reaction Time to presumed
neuropathological status supports the hypothesis that RT
performance accesses a cardinal functional dimension of the central
nervous system."
F.J.PIROZZOLO & E.C.HANSCH, 1981, Science 214.
"The N-weighted mean [of 35 correlations from 29 independent
samples, involving a total N of 1,558] between RT slope and "IQ"
is -.117.... To be sure, these are small correlations, although
they are significant beyond the .001 level."
A.R.JENSEN & P.A.VERNON, 1986, Intelligence 10.
"The twelve WISC-R subtests' correlations with RT slope were
correlated +.80 with the subtests' g loadings...."
A.R.JENSEN, 1987, in S. & C. Modgil, Arthur Jensen:
Consensus and Controversy. Brighton : Falmer.
"[R.L.Thorndike's (1987, Person.&Indiv.Diffs.8)
finding of a g-loading of .58 for discrimination reaction
time] indicates the central role which reaction time plays in
whatever is common to tests of cognitive ability, certainly no-one
would have predicted on the basis of current environmentalistic
theories of intelligence, emphasizing social learning, that discrimination
reaction time would be a better measure of general ability (as
measured by the Guilford tests) than would be reading, comprehension,
general information, or judgement! Findings such as these demand
an explanation in theoretical terms, and it is interesting that
this important finding has been completely disregarded by writers
in the field up till now." H.J.EYSENCK, 1988, Intelligence
12.
"A correlation between speed of information processing, as
measured by reaction time on various elementary cognitive tasks
and....psychometric g is now well established. ....The
average speed of information processing on [a Semantic Verification
Task - checking whether the letter 'A' precedes 'C' in screened
displays of three letters] is about thirty per cent greater in
the gifted than in their siblings...." A.R.JENSEN
et al., 1989, Personality & Individual Differences
10.
"In the early 1970's many investigators conducted studies
of various cognitive tasks given in conjunction with more conventional
paper-and-pencil cognitive ability tests. Illustrative work may
be cited: Hunt et al.'s (1973, in G.Bower, The Psychology
of Learning and Motivation) correlational studies of several
cognitive tasks as related to performance on verbal and quantitative
sections of the Scholastic Aptitude Test, and later a major factor-analytic
study by Hunt, Lunneborg and Lewis (1975, Cognitive Psychology
7), Chiang and Atkinson's (1976, Memory & Cognition
4) study of two short-term memory tasks as related to S.A.T.
scores, Hundal and Horn's (1977, Applied Psychological Measurement
1) factor-analytic study of mental abilities and short-term
memory performances, and Jensen's (1979, Creative Science &
Technology 2) study of simple and choice reaction times as
related to intelligence test scores."
J.B.CARROLL, 1993, Human Cognitive Abilities.
Cambridge University Press.
"....in the year of publication of his work On the
Origin of Species, Charles Darwin wrote...."I suppose
I am a very slow thinker." His son Francis remarks that Charles
Darwin "used to say of himself that he was not quick enough
to hold an argument with anyone, and I think this was true."
J. R. BAKER, 1974, Race. Oxford University Press.
"Binet found that his daughters and their small friends had
average reaction times about three times longer than typical
adults', but with greater variability. On some trials, the children
responded just as quickly as adults, but on others they were slower.
Since the children could sometimes match the adult speed,
Binet concluded that the crucial factor differentiating children
from adults was not reaction time per se, but rather the
ability to sustain attention to the task."
R.E.FANCHER, 1985, The Intelligence Men. New York : Norton.
"....mean reaction time is an almost worthless measure
for assessment of individual differences."
P.M.A.RABBITT, 1982.
"[Apparently] few age differences in speed of processing
for simple visual forms exist from kindergarten to adulthood."
F.J.MORRISON, 1982, Journal of Experimental Child Psychology
34.
"....Jensen forgets the problem of positive bias inherent
in any meta-analysis: studies that do not result in rejection
of the null hypothesis are not as likely to be submitted for publication,
and, if they are submitted, they are not likely to be published."
L.E.LONGSTRETH, 1986, Intelligence 10.
"Factor analytic studies of the WAIS-R subscales reveal the
existence of a performance or nonverbal (visual motor, space-perception,
etc.) organisation component (Wechsler, 1958). A significant portion
of the variance in the relation between Decision Time and IQ [here
found to be -.34 in 28 college students] may be due to this factor."
M.A.SMALL et al., 1987, Journal of Genetic Psychology
148.
"One can only conclude that the evidence for relations between
reaction time(RT) and motor time(MT) variables and intelligence
is mixed and incomplete. ....My hunch is that many [of Jensen's]
RT and MT findings can be explained by supposing that lower-IQ
individuals are less capable of meeting the attentional requirements
of the RT-MT task."
J.B.CARROLL, 1987, in S. & C. Modgil, Arthur Jensen:
Consensus and Controversy. Brighton : Falmer.
"Recent claims of linear relationships between mean RTs and
RT variance, and between both of these factors and chronological
age and IQ test scores, fail to replicate after very intensive
testing. ....[Other experiments] show that while IQ test scores
correlate strongly with practised performance on complex interactive
video-games, these associations mainly reflect individual differences
in rates of acquisition of complex control relationships, and
differences in strategic management of complicated scenarios.
They only very weakly reflect individual differences in simple
information processing rate. The implications of these data for
models of individual differences in skilled performance, and for
recent re-evaluations of theories of intelligence, are discussed
with some relish."
Patrick RABBITT, 1988, to 24th International Congress of
Psychology, in Sydney (S492).
"[Our] correlations between Scholastic Aptitude Test (SAT)
scores and Reaction Time (RT) and Motor Time(MT) intercept and
slope estimates are consistent with the hypothesis that correlations
between Hick parameter estimates and measures of mental ability
or achievement occur because of ability-related differences in
automatization of responding to the task, rather than being due
to ability-related differences in rate of execution of elementary
mental operations. The results from the present study call into
question the typical interpretation of findings related to the
Hick paradigm...."
K.F.WIDAMAN & J.S.CARLSON, 1989, Intelligence 13.
"[In view of the reports by Kyllonen & Christal (1989,
Intelligence 14) and Carpenter et al. (Psychol.
Rev. 97)] one is allowed to speculate....whether the general
factor presumably measured by the Raven Progressive Matrices test
is principally a measure of the capacity of working memory....
[However,] as yet there has not been sufficient work on measuring
working memory, and the validity and generality of the concept
have not yet been well established in individual difference research."
J.B.CARROLL, 1993, Human Cognitive Abilities.
Cambridge University Press.
"It is generally agreed by philosophers of science that
important contributions which have a revolutionary impact on science
are often methodologically inadequate, reveal many anomalies,
and may indeed be factually erroneous."
H.J.EYSENCK, 1987, replying to J.B.Carroll (1987) {above} in
S.& C.Modgil, Arthur Jensen: Consensus and Controversy.
Brighton : Falmer.
"In his "specificity of mind" view, Ceci
(1990) asserts that relationships between microlevel processes
(measured by elementary cognitive tasks (ECT's)) and macrolevel
processes (assessed through psychometric intelligence tests) are
only due to their sharing a common knowledge base....[We found
that] high speed of information processing in ECTs is related
to high psychometric intelligence. All three ECTs involving different
knowledge bases (verbal, numerical, figural) correlated significantly
with all three content factors in the Berlin Model of Intelligence
Structure (BIS). This rather supports the "singularity
of mind" view."
A.C.NEUBAUER & V.BUCIK (Karl-Franzens University, Graz),
1995, 'The mental speed - IQ relationship: singularity or specificity
of mind?' From the abstract of an address to International Society
for the Study of Individual Differences, meeting in Warsaw.
(iv) Is intelligence related to speed of 'intake'
of information
- i.e. to 'sensory reaction time' or 'inspection time'?
"Aquinas made the interesting but questionable observation
that 'those who have the best sense of touch have the best intelligence.'
It is interesting to note that Spearman, in his first investigation
into intelligence [1904, Am.J.Psychol.] found that sensory
discrimination, including tactile discrimination, correlated well
with general intelligence."
L.S.HEARNSHAW, 1987, The Shaping of Modern Psychology.
London : Routledge.
"The trials I have as yet made on the sensitivity of different
persons confirm the reasonable expectation that it would on the
whole be highest among the intellectually gifted."
Francis GALTON, 1883.
"The discovery that there were individual differences in
the time needed to perceive a stimulus was made by James McKeen
Cattell while he was carrying out investigations for his Ph.D.
in Leipzig. ....Cattell's concern was that the reaction time was
too 'motor' and that the elements of the reaction time would reveal
more about the timing of mental events. Cattell devised his "perception
time" as the time needed to make a single discrimination,
i.e., the time needed to see, freed of all constraints
to respond quickly....
[He reported] "I tried to make the determinations on two
rather obtuse porters, but their consciousness did not seem able
to take up at all such delicate impressions. They required three
times as long as educated people to read a word."
I.J.DEARY, 1988.
"A reasonable conclusion from the research on visual masking
[in adulthood] is that the rate of processing visual stimuli is
slower with increased age."
T.A.SALTHOUSE, 1982, Adult Cognition: an Experimental Psychology
of Human Ageing. New York : Springer.
"Dempster (1981, Psychol.Bull.) examined ten possible
sources of individual and developmental differences in [memory-span]
performance. ....His conclusion was that only item identification
[i.e. recognition speed] appeared to be a major source of such
differences."
M.S.HUMPHREYS, 1983, Individual Differences in Cognition 1.
"Amongst young children (of ages six to twelve years), recent
studies....have found correlations of about -.60 between Inspection
Time and raw scores [i.e. Mental Age] on Cattell's Culture
Fair Test of Intelligence. ....At least it is clear that the reported
IT/IQ correlations do not lend themselves to being explained as
socio-cultural constructions that reflect Western capitalism's
demands for and differential stimulation of intelligence."
C.R.BRAND, 1984, in C.J.Turner & H.B.Miles, The Biology
of Human
Intelligence. North Humberside : Nafferton Books.
"....perhaps psychologists would have come to understand
g earlier if they had considered that, in English, the
term 'intelligence' has particular reference to information-gathering
(as in its classic military usage) rather than to the final use
of such information, which is often distorted by features of motivation
and temperament."
C.R.BRAND, 1984, in J.Nicholson & Halla Beloff,
Psychology Survey 5. Leicester : British Psychological
Society.
"....measures of 'inspection time' (IT) for extra-elementary
displays continue to show strong correlations (of around -.60)
with measures of IQ and mental age."
C.R.BRAND, 1985, Behavioral & Brain Sciences 8.
"Several studies (Bornstein & Sigman, 1986; Rose &
Slater, 1986) have established that looking time [the duration
for which novel material is inspected by an infant] is strongly
[inversely] related to....later IQ. It is a curious relationship,
given the simplicity of the earlier ['looking time'] measures
and the very general nature of the IQ test."
P.E.BRYANT, 1992, Nature, 27 viii.
"Inspection Time may reflect subtle cognitive factors, associated
with the encoding of stimulus elements, that can influence mental
speed."
T.NETTELBECK, 1982,
Quarterly Journal of Experimental Psychology 34A.
"What we fear is that research on attentional contributions
to intelligence could experience a fate similar to that of some
of the research on basic information-processing determinants of
ability: namely, establishing that individual differences exist,
but not knowing what those individual differences really mean."
L.A.COOPER & D.T.REGAN, 1982, in R.J.Sternberg,
Handbook of Human Intelligence. Cambridge University Press.
"Inspection Time appears to be a threshold variable which
can successfully distinguish retarded and non-retarded samples,
while within either group, or at least within a group of above-average
intelligence, it does not appear to correlate with measures of
intelligence nor with other measures of cognitive processing."
P.A.VERNON, 1983, Intelligence 7.
"Brand and Deary (1982) have reported some extremely high
correlations (around -.80) between IQ and a measure derived from
reaction time needed to indicate the longer of two vertical lines.
They refer to the time needed to do this task as "inspection
time". Although these correlations seem most impressive at
first, they were derived from very small samples of subjects,
who often differed extremely widely in IQ, ranging from the mentally
retarded to the gifted. Using more typical samples, other investigators,
such as Nettelbeck (1982, Qu.J.Exptl Psychol.), have obtained
the more typical level of correlation for tests of choice reaction
time (about -.30)."
R.J.STERNBERG, 1985, in R.J.Sternberg, Human Abilities.
New York : Freeman.
"....our impression is that the relation between intelligence
and IT is not very clear, particularly due to the great variability
in results."
Marie-Paule LUBIN & Jose Muniz FERNANDEZ, 1986,
Personality & Individual Differences 7.
"Reports of very high (.60) correlations between IQ and measures
of timed performance have not been substantiated and can usually
be attributed to the inclusion of disproportionate numbers of
retarded subjects in the samples."
N.J.MACKINTOSH, 1986, British Journal of Psychology 77.
"If anything, the essence of intelligence would seem to be
in knowing when to think and act quickly, and knowing when to
think and act slowly."
R.J.STERNBERG, 1987, in S. & Celia Modgil, Arthur Jensen:
Consensus and Controversy. Brighton : Falmer.
"Inspection Time was not significantly related to IQ or to
any of the WAIS subtests among strategy users [i.e. among subjects
who could 'penetrate the backward mask']. In the non-users, however,
Inspection Time was highly correlated with Performance IQ and
with scores on two of the subtests."
B.MACKENZIE & Elizabeth BINGHAM, 1985,
Australian Journal of Psychology 37.
"We are 'Doubting Thomases' no more. The association between
visual inspection accuracy as measured in a backward-masking paradigm
and IQ appears to be more than the predictable consequence of
small and heterogeneous samples."
L.E.LONGSTRETH et al., 1986,
Personality & Individual Differences 7.
"The most important point to emerge from these three studies
is that inspection time is related to IQ differences in children.
Further, the relationship holds across four chronological years
and when the effects of Mental Ages (MA) are removed.... It must
be emphasized that the sample is composed of normal school children
and that this effect cannot be attributed to the inclusion of
any mentally retarded subjects.... [The results suggest that]
the reason for the IT/IQ correlation is that both measures are
related to fundamental aspects of information processing, rather
than the contents of knowledge structures."
M.ANDERSON, 1986, Personality & Individual Differences
7.
"The apparent independence of Inspection Time from the effects
of previous experience, its impressively high reliability of .87
in the whole sample, and its substantial correlation of .66 with
the measure of intellectual level in a specifiable part of the
whole subject sample, jointly confirm the promise of the measure
as a tool for experimental research on intelligence."
B.MACKENZIE & S.CUMMING, 1986,
Personality & Individual Differences 7.
"....it is not clear that low-IQ subjects suffer from commonplace
attentional failures that could simply lengthen their ITs: even
mentally subnormal subjects are quite capable of near-perfect
performance on IT-like tasks so long as target stimuli are exposed
for more than a fifth of a second."
C.R.BRAND, 1987, in S. & Celia Modgil, Arthur Jensen:
Consensus and Controversy. Brighton : Falmer.
"Results [of our experiments] indicate that college students
differ in performance on a very simple auditory recognition task,
and that as much as 25% of this variability is predictable from
differences in IQ. Given the simplicity of the task, little room
remains for variability related to differences in reasoning or
strategy selection.... Galton's (1883) suggestion of an important
link between 'the avenue of the senses' and good sense may be
not as far-fetched as previously supposed."
N.RAZ, L.WILLERMAN & M.YAMA, 1987,
Personality & Individual Differences 8.
"....inspection time (a paradigm invented by T.Nettelbeck
& M.Lally, 1976, Brit.J.Psychol.) is highly correlated
(negatively) with IQ, enabling high-IQ subjects to correctly perceive
very simple precepts presented very rapidly, such as the respective
length of two lines. The most recent studies (unpublished) on
the topic indicate that correlations in the .50's can be obtained
from large random samples."
H.J.EYSENCK, 1987, in S. & C. Modgil, Arthur Jensen:
Consensus and Controversy. Brighton : Falmer.
"....evidence [from some thirty studies] suggests a correlation
of -.50 between IT and IQ among normal adults - higher than
has generally been found between IQ and [other] laboratory procedures
for measuring speed of information processing. Results from children
are not clear with respect to an IT-IQ correlation, but strongly
support the theory that mental speed increases with mental age.
In broad terms, therefore, the outcome is consistent with Brand's
theory but does not support speculation that IT might supplement
or replace existing psychometric procedures."
T.NETTELBECK, 1988, in P.A.Vernon, Speed of Information-
Processing and Intelligence. Norwood, New Jersey : Ablex.
"....IT presents many advantages as a test of basic processing
speed. IT shows little practice effect and may be used in repeated
testing.... IT continues to remain one of the few correlates of
general mental ability that has not been accused of some kind
of bias. Unlike RT, IT has the appearance of a task that indexes
one basic process: the speed of intake of sensory information.
Unlike Average Evoked Potential {see below}, IT may be tested
relatively quickly by workers using non-specialist equipment."
I.J.DEARY, 1988, Human Evolution 3.
"Despite....only moderate reliability in the measuring procedures,
the correlation between IT and raw scores on the WISC-R [in 47
six-year-old children of mean IQ 113, s.d. = 10] was -.57....
We believe that control processes are involved, so that the "mental
speed" indexed by IT is probably not a primary characteristic
of some sampling mechanism but, instead, a secondary consequence
of less efficient information processing."
T.NETTELBECK & R.YOUNG, 1989,
Personality & Individual Differences 10.
"[My] conclusion is that there are attentional influences
on IT performance, but they detract from, rather than induce,
the relationship between IT, age and intelligence."
M.ANDERSON, 1989, Personality & Individual Differences
10.
"An association between g and encoding speed can account
for many of the cognitive correlates of g, such as the
Posner NI-PI measure (Keating & Bobbitt, 1978), inspection
time, and even digit span, which appears to depend on speed of
item identification (Dempster, 1981)."
G.MATTHEWS & Lisa DORN, 1989, Intelligence 13.
"[Our] results challenge Mackintosh's (1986, Brit.J.Psychol.),
Todman and Gibb's (1985, Brit.J.Psychol.) and Vernon's
(1986, Person.& Indiv.Diffs.) suggestions that the
IT-IQ correlation depends on the inclusion of retarded subjects.
When the IT-IQ correlations were corrected for restriction of
ability range, the correlations became slightly larger than the
-.50 result predicted by Nettelbeck (1987, in P.A.Vernon, Speed
of Information-Processing and Intelligence)."
I.J.DEARY, P.G.CARYL, V.EGAN & D.WIGHT, 1989,
Personality & Individual Differences 10.
"In general, the pattern of correlations of subjects' IT
estimates with the parameters of the P200 and P300 components
of their Average Evoked Potentials of the brain {see below} to
the IT stimuli....argues strongly for the view that the IT measures
the speed of that stage of information processing at which the
stimulus is encoded or transferred into Short Term Memory from
a sensory register...."
Y.ZHANG, P.G.CARYL & I.J.DEARY, 1989,
Personality and Individual Differences 10.
"The information-processing implications of habituation [to
a novel stimulus] and its individual differences and reliability
together suggest that habituation in infancy may harbor concurrent
or predictive validity for cognitive functioning in childhood....
Infants and young children who habituate efficiently tend also
to prefer complexity, show advanced sensorimotor development,
explore their environment more rapidly, play in relatively sophisticated
ways, solve problems quickly and attain concepts efficiently,
and excel at oddity identification, picture matching, and block
configuration in traditional tests of intelligence. Further, infants
who are expected to differ in intelligence in later life show
commensurate individual differences in habituation of attention.
Perinatal risk adversely affects habituation, and trisomy-21 is
associated with less efficient habituation."
Marc H. BORNSTEIN, 1989, Seminars in Perinatology 13.
"Inspection Time was measured {in 91 testees of IQ's ranging
quite widely around 110} using a curve-fitting procedure that
was less susceptible to variable task performance. IQ correlated
significantly with I.T. (r = - .624), and Odd-Man-Out decision
time (DT = .365) as well as with CRT DT (r = .28)."
T.C.BATES & H.J.EYSENCK, 1993, Intelligence 17.
"It is not known for certain what the noncognitive component
of RT consists of, most of it is probably variance in the purely
sensorimotor aspects of RT performance. This may also account
for the generally higher g loading - about -.50 - of
inspection time (i.e. the speed of making simple visual
or auditory discrimination, which involves no motor component)
than of RT based on any single elementary cognitive task."
A.R.JENSEN, 1994, 'Phlogiston, animal magnetism and intelligence.'
In D.K.Detterman, Current Topics in Human Intelligence 4:
Theories of Intelligence. Norwood, NJ: Ablex.
"....when scores {of 107 secondary schoolchildren, IQ = 11}
on the first unrotated principal component extracted from three
auditory [discrimination] tests were correlated with the scores
on the first unrotated [IQ] component extracted from the Mill
Hill and Raven IQ's Pearson's correlation was .52."
I.J.DEARY, 1994, 'Intelligence and auditory discrimination.'
Intelligence 18.
"[Richard] Gregory suggests that if visual perception is
seen as involving active (though unconscious) decision-making,
and not simply the passive registering of input, then we can attribute
higher intelligence to perception."
Annette KARMILOFF-SMITH, 1994, Times Higher Educational Supplement,
21 x. (Reviewing Jean Khalfa(ed.) , What is Intelligence?,
Cambridge University Press.)
"....habituation-based measures [of 'infant intelligence']
obtained from babies at ages ranging from three months to a year,
are significantly correlated with the intelligence test scores
of the same children when they get to be 2 or 4 or 6 years old
(e.g. Columbo, 1993, Infant Cognition). A few studies have
found such correlations even at ages 8 or 11 (Rose & Feldman,
1995, Develop. Psychol. 31). A....meta-analysis, based
on 31 different samples, estimates the average magnitude of the
correlations at about .36."
Extract from Intelligence: Knowns and Unknowns - Report of
a Task Force established by the Board of the Scientific Affairs
of the American Psychological Association, 1995. Washington,
DC : APA Science Directorate.
(v) What could be the physical basis of intelligence
(in the nervous system)?
"In the mentally defective the nerve cells are few in number,
they have relatively few branches, and, as seen under the microscope,
they are arranged in a relatively unsystematic and higgledy-piggledy
fashion."
Cyril BURT, circa 1970, in C.James, Modern Concepts
of
Intelligence. 94, Chatsworth Road, Croydon : R.S.Reid.
"A .78 correlation (p<.005, one-tailed) was found
between the edited String Length 256 [a measure of Average Evoked
Cortical Potential-cf. D.E. & A.E. Hendrickson, 1980,
Person.& Indiv.Diffs.] for ten subjects [having satisfactory
inter-electrode resistances] and their total raw scores on the
Alice Heim 4 Test of General Intelligence [across an IQ range
of approximately IQ 105-140."
I.C.FRASER, 1984, Edinburgh University : Psychology Honours
Thesis.
"I regard mental speed as a secondary consequence of differences
among individuals in ability to process information accurately,
inaccurate processing leads to delays and thus to longer latencies."
H.J.EYSENCK, 1984, Behavioral & Brain Sciences 7.
"The distinction between stimulus evaluation stages [of information
processing] and response selection stages has been supported by
brain event related potential (ERP) studies. The latency of the
P300 component of the ERP is sensitive to changes in stimulus
complexity but not to changes in response complexity...."
H.NAYLOR et al., 1985, Psychopharmacology 86.
"....the findings of the present study indicate that ACTH
4-9 may reduce temporal thresholds of recognition of single letters
presented with a tachistoscopic technique. The results can be
interpreted to indicate a beneficial effect of the peptide on
automatic, pre-attentive levels of information processing involved
in the transfer of information from the peripheral icon to the
cortical centres, i.e. from iconic storage to short-term memory."
G.D'ELIA et al., 1985, Neuropsychobiology 13.
"....we should accept that elementary cognitive tasks such
as choice reaction times, inspection times and EEG evoked potentials
show stronger positive correlations with g than was previously
believed."
Philip E. VERNON, 1985.
"Height, weight, cranial size, brain size, various blood
groups, serum level in the blood, and basal metabolic rate are
some of the researched [physical] correlates of IQ.... Intellectually
gifted children, on average, are found to be much more myopic
than their less gifted siblings.... Gifted children have more
allergies than their siblings."
A.R.JENSEN, 1986, at a conference in Blackwood, Virginia.
"Intelligence, as the sum total of all cognitive processes,
entails planning, coding of information, and attention / arousal.
....The structural basis for planning is the frontal lobes. ....The
structural base for [coding] processes is the posterior part of
the human brain.... An adequate level of arousal and attention
is a prerequisite for coding and planning. The function is located
in the brain stem."
J.P.DAS, 1986, in R.J.Sternberg & D.K.Detterman,
What is Intelligence? Norwood, New Jersey : Ablex.
"Changes of simple visual reaction time were analysed in
two groups of unilaterally brain-damaged patients in order to
evaluate to what extent properties of lesions, clinical parameters
and experimental variables might influence speed of motor response.
The results confirmed that brain damage, independent of its site,
produces a retardation of speed."
A.TARTAGLIONE et al., 1986, Neuropsychologia 24.
"A most exciting recent discovery is the genetic link between
Alzheimer's disease and Down's syndrome. G.C.Glenner and his colleagues....[have]
demonstrated that the amyloid beta protein (a major component
of the neurofibrillary plaque that accumulates in the brains of
individuals with Alzheimer's disease) is identical with the protein
that accumulates in apparently identical lesions in the brains
of all individuals with Down's syndrome who are over 35 years
old."
D.PATTERSON, 1987, Scientific American 257, viii.
"[In Alzheimer and control patients (Chase et al.,
1984)] the correlations between overall resting cortical glucose
use and IQ scores were [.68 for Full Scale IQ, .61 for Verbal
IQ, and .56 for Performance IQ]."
I.J.DEARY, 1988, Mensa Research Journal(USA), No.24.
"A well-known drug, nicotine, was reported [at a conference
of pharmacologists in Athens - see also Brit.Med.Journal,
August 1991] to enhance certain aspects of test performance in
patients early in the course of Alzheimer's disease. [Other results]
indicate significant [nicotine-] dose-related improvements in
performance in young volunteers and in [patients suffering Alzheimer-type
dementia] [on a] test of rapid information processing."
T.W.ROBBINS, 1988, Nature 336, 17 xi.
"Performance on the Raven's Advanced Progressive Matrices
showed significant negative correlations [around -.75, p
<·05] with cortical metabolic rate. ....The results (with
young adults)....suggest that there is an inverse relationship
between abstract reasoning and glucose use in the brain as a whole."
R.J.HAIER et al., 1988, Intelligence 12.
"Willerman et al. (1989, paper to 19th Annual Meeting
of Behavior Genetics Association, Charlottesville, Virginia) have
reported a substantial relationship between magnetic resonance
imaging (MRI) measurements of brain size and mental test scores
in a college sample, controlling for sex and overall body size."
A.R.JENSEN, 1989, draft paper 'Understanding g
in terms of information processing.'
"An analysis of IQ in relation to head size (and, by inference,
brain size) was performed on some 14,000 children....at ages 4
and 7 in the National Collaborative Perinatal Project. Within
each race x sex group, IQ is significantly correlated {at around
.25} with head [circumference], age and body size having been
partialled out..... There are both race and sex differences in
head size, although the sex difference in IQ is nil."
A.R.JENSEN & F.W.JOHNSON, 1994, Intelligence 18.
"Over the past 3½ million years the brains of our hominid
ancestors have more than quadrupled in size. The earliest australopithecine
brain was not much larger than a modern chimpanzee's, little more
than 400 cc. From then onwards there has been a more or less steady
increase in brain volume through Homo sapiens and Homo
erectus to modern Homo sapiens, which averages not
much under 1800 cc in some populations. And stone artefacts indicate
that human material culture has been increasing in complexity
in step with the increase in brain volume."
C.B.GOODHART, 1995, The Galton Institute Newsletter, No.
16, iii.
"Thinking in terms of physiological processes is extremely
dangerous in connection with the clarification of conceptual problems
in psychology. Thinking in terms of physiological hypotheses deludes
us sometimes with false difficulties, sometimes with false solutions.
The best prophylactic against this is the thought that I don't
know at all whether the human I am acquainted with actually have
a nervous system."
L.WITTGENSTEIN, Remarks I 1063, cited by A.J.Ayer,
Ludwig Wittgenstein. London : Weidenfeld and Nicholson,
1985.
"....there are no data to indicate....that the brain is....a
thinking and controlling organ and the locus of intelligence.
The brain is no more responsible for an individual's psychological
activity than the heart, lungs, stomach or endocrine system."
S.W.BIJOU & E.DINITZ-JOHNSON, 1981, Psychological Record
31.
"Even if IQ correlated perfectly with some physiological
measure, what would this correlation tell us about (a) the cognitive
processes that underlie intelligent behaviour, (b) what constitutes
intelligent behaviour, or (c) why IQ tests themselves are so imperfect
as predictors of intelligent behaviour in the real world? ....intelligence
should be studied at multiple levels, with our goals being the
ultimate linkage of these levels."
R.J.STERNBERG, 1984.
"A most promising development has been the correlation of
some aspects of the auditory evoked potential with measures of
intelligence. ....The size of [Blinkhorn & Hendrickson's,
1982] correlations (from .50 to .75 [between IQ and AEP]) is of
the same order of magnitude as correlations between the subtests
of an intelligence test. ....[However] this finding remains highly
controversial. The relatively small size of the samples involved
and the continuing lack of any confirmation of their two reports
does not inspire confidence."
J.A.C.EMPSON, 1986, Human Brainwaves. London : Macmillan.
"There's no difference between your brain and the brain of
an Einstein or a Mozart or a Shakespeare."
Stated in the first broadcast of the 'Open College' on
UK TV Channel IV, September, 1987.
"....the existence of manifest individual differences in
speed or choice reaction time, whether in Jensen's task or others,
does not imply isomorphic underlying differences in speed or reaction
time at the neurological level."
R.J.STERNBERG, 1987, in S. & Celia Modgil, Arthur Jensen:
Consensus and Controversy. Brighton : Falmer.
"....'natural frequency' [of electro-encephalographic patterns],
expressed as radians per second, is a direct measure of the speed
of thalamocortical transmission, and it is clear from the present
findings that an intermediate speed of neural transmission
is associated with higher IQ. Consequently, it seems that the
speed of neural transmission would not provide a basis for explaining
the frequently small but consistently negative correlations between
RT and IQ or between IT and IQ."
D.L.ROBINSON, 1989, International J. Neuroscience 46.
"For neuroscientists, exploring the microscopic intricacies
of the most complex object we know, attributing significance to
gross measures of size is frankly vulgar. ....Rushton (1995, Race,
Evolution & Behavior, Transaction) cites correlations
[between brain size and IQ] of .38, .40 and .43. He does not,
however, mention that the researchers who obtained the last of
these figures found that correcting for age reduced it to .22,
and further corrections for sex and head size made it all but
vanish completely (Raz et al., 1993, Intelligence 17).
The others provide more authentic support for his views, though
that is unsurprising in the case of the .40 figure, since it was
generated by colleagues of his at the University of Western Ontario."
Marek KOHN, 1995, The Race Gallery: the Return of Racial Science.
London : Jonathan Cape.
"Now that links between features of the AEP and IT and IQ
have been clearly established, it should be easier to argue productively
about the mechanism underlying the correlations that have been
observed."
Y.ZHANG, P.G.CARYL & I.J.DEARY, 1989, Person. & Indiv.Diffs.
10.
"The cortical event-related potential (ERP) waveform path
length (string measure) - previously found by Hendrickson (1982,
A Model for Intelligence) to correlate very highly with
psychometrically assessed intelligence - was found in the present
study to correlate significantly positively [though at a more
modest .41] with intelligence test scores."
D.G.GILBERT, et al., 1991, Personality & Individual
Differences 12.
"We found significant correlations between IQ and [the size
of] many of the [brain] structures that were measured [in 67 normal
Iowa adults of mean Wechsler IQ 116, standard deviation 14]. In
all analyses, height was [partialled out] in order to correct
for individual differences in body size. A significant positive
[partial] correlation was observed between intracranial volume
and....full-scale IQ (r = .38, p<.01).... Within subcortical
brain regions, there was a differentiation between subcortical
structures that subserve functions such as memory or language
and those that subserve habit formation, motoric function, or
emotional function. That is, a significant [partial] correlation
was observed between intelligence and hippocampal volume [c.
r = .37], but not between IQ and the volume of the caudate
[c. r = .07, n.s.]."
Nancy C. ANDREASEN et al., 1993, Amer. Journal of Psychiatry
150.
"A variety of measures of EEG and of average evoked responses
correlate with intelligence.... [However,] it is unlikely that
any single index of brain electrical activity will provide a "biological
measure of g" which can replace conventional tests
of intelligence."
I.J.DEARY & P.G.CARYL, 1993, 'Intelligence, EEG and Evoked
Potentials.' In P.A.Vernon, Biological Approaches to the Study
of Human Intelligence, Norwood, NJ : Ablex.
"In the Daily Record of March 8, 1994 (definitely
not April 1), an item entitled "Your Brains Are
in Your Bum, says Doc" describes how psychologist Milton
Sternes (ho ho) of Chicago, after a five-year study into intelligence
and body shapes, has discovered that "people with ample behinds
score an average 26 points higher on IQ tests" and has reported
this in his book "Big Butt, Bigger Brains.""
Bill McPHILLIMY, 1994, 'Media Watch', Bulletin of the Scottish
Branch
of the British Psychological Society.
"Further research [into the physical basis IQ differences]
should be led on the right track by disentangling the cause of
the confirmed correlation between glutathione peroxidase and IQ."
V.WEISS, 1995, from the abstract of an address to International
Society for the Study of Individual Differences, meeting in Warsaw.
"Recent research on the relationship between brain volume
(measured via magnetic resonance imaging, or MRI) and IQ has indicated
a moderate positive correlation of about .40 between the two
variables. The purpose of the present research is to further replicate
this finding in a sample of 100 healthy adult males comprising
50 pairs of brothers...In 62 subjects (31 pairs of brothers) collected
to date, it was found that brain volume correlated significantly
with IQ (r = .277, p < .05...."
J.C.WICKETT, P.A.VERNON & D.H.LEE, 1995, from the abstract
of an address to International Society for the Study of Individual
Differences, meeting in Warsaw.
"Using data from magnetic resonance imaging (MRI), autopsy,
endocranial measurements and other techniques, we show that (1)
brain size is correlated with cognitive ability about .44 using
MRI; (2) brain size varies by age, sex, social class and race;
and (3) cognitive ability varies by age, sex, social class and
race. ....it is clear that the direction of the brain-size/cognitive-ability
relationships described by Paul Broca (1824-1880), Francis Galton
(1822-1911) and other nineteenth-century visionaries is true,
and that the null hypothesis of no relation, strongly advocated
over the last half century, is false. ....Rushton & Osborne
(1995, Intelligence 20) studied genetic and environmental
contributions to cranial size among 236 pairs of adolescent twins
[....and found the] genetic contribution to cranial size....ranged
from 38% to 51%"
RUSHTON, J.P. & ANKNEY, C.D. (1996). 'Brain size and cognitive
ability: correlations with age, sex, social class and race.'
Psychonomic Bulletin & Review 3, 1, 21-36.
(vi) Will cognitive psychology explicate g if other
approaches have failed? {See also Quotes XIII.}
"Cognitive psychology, so called, is little more than a promise
to pay, without evidence that there is any balance in the bank
to meet creditors' demands."
H.J.EYSENCK, 1980.
"Research conclusions in artificial intelligence have shown
that intelligence is equivalent to comprehension, i.e. the
acquisition or construction of linguistic structures appropriate
to the world of objects they represent. It has also shown that
comprehension and learning are basically similar because both
are mechanisms to build linguistic representations of meaningful
information.... Intelligence is an information-gathering process
as much as it is a search process.... Intelligence is the production
of new information, i.e. to find new elements and relations
to be added to the data bases stored in memory."
F.FRISCHKNECHT, 1986, Behavioural Science 31.
"There is really little argument among cognitive psychologists
about the existence of a g or general intelligence factor.
They would also support the existence of various narrower factors
such as spatial ability. Any or all of these factors may indeed
have temporal aspects, the question is how much the difference
between high and low ability is manifested in processing time."
J.B.CARROLL, 1987, replying to H.J.Eysenck, in S. & C.Modgil,
Arthur Jensen: Consensus and Controversy. Brighton : Falmer.
"....the hard work is done by neuropsychology and differential
psychology....yet cognitive psychology gets the credit."
I.J.DEARY, 1992, Nature 359, 3 ix.
(Reviewing M.Anderson, Intelligence and Development: A Cognitive
Theory. Oxford Blackwell.)
Epilogue - continuing arguments
"....we believe that individual differences in performance
on most measures of mental speed are determined more by differences
in the quality of meta-componential processing than by differences
in speed of performance components."
Diana B. MARR & R.J.STERNBERG, 1988, in P.A.Vernon, Speed
of
Information Processing and Intelligence. Norwood, NJ :
Ablex.
"It is argued that the relationship between IQ and IT must
be a power function (rather than a linear one), and the correlation
between log IQ and log predicted IT was found to vary systematically
as a function of the information in the inspected item, the greatest
correlation (r = .87; p<.001) being for items
containing about 15 bits - that is, items containing approximately
the same amount of information as verbal material. This may mean
that g is a measure of the time an individual takes to
process verbal information."
P.HOLOHAN & H.V.SMITH, 1992, 'Individual differences in immediate
recall, inspection time and intelligence'.
Irish Journal of Psychology 13.
"....we do not, even now, know what intelligence tests measure,
and we are equally hard put to say with any coherence what intelligence
is."
P.E.BRYANT (Professor of Psychology, University of Oxford),
1992, Nature 358, 20 viii.
"....regarding IT as a 'pure' measure of general intelligence
is probably no longer tenable. Nor is the use of IT motion after-effects
demonstrably strategic in origin."
V.EGAN, 1994, British Journal of Psychology 85.
"Between 1884 and 1890, Galton operated a laboratory in the
South Kensington Museum.... Though Galton never analyzed the data,
Johnson et al. (1985, Amer.Psychol.) did and found
them to be surprisingly consistent with [recent] data. {However,}
Wissler (1901), a graduate student working with McKeen Cattell,
was given {Cattell's data on line bisection, auditory RT, least
perceptible difference between weights, two-point threshold and
color naming in Columbia freshmen} to analyze [and concluded]
"While the tests do seem to have some value when applied
to children in the lower schools, they tell us nothing as to the
general individual worth of college students or of adults."
....Sharp (1898) [a student in Titchener's laboratory] [found]
no relationship between test results [memory, imagery, discrimination
and attention] and academic performance [in seven fellow graduate
students].... The graduate students obviously represented a highly
curtailed range of intellectual ability, but no one seems to have
recognized that this methodological problem would have substantially
reduced the size of the correlations obtained. It is not surprising
that Sharp did not realize the problem, because correlation was
a new technique. It is surprising that many investigators today
still make the mistake of using samples with curtailed ranges
even though the effects of restricted ranges on correlation coefficients
are well known."
D.K.DETTERMAN, 1994, 'Intelligence and cognitive abilities.'
In D.K.Detterman, Current Topics in Human Intelligence 4:
Theories of Intelligence. Norwood, NJ: Ablex.
"Despite hundreds of factor analytic studies on psychometric
g, we scarcely know more about its nature than did Spearman seventy
years ago. Using elementary cognitive tasks (ECTs) to unpack its
properties has also been disappointing, though some modest advances
have been made."
L.WILLERMAN, 1995, address to International Society for the Study
of Individual Differences, meeting in Warsaw.
"....it may be that bright subjects process approximately
the same number of discrete stimuli per unit time (with normal
attentional-blocking separating successive stimulus processing
and attentional refixation cycles). The greatest advantage in
g, then, may lie in high quality processing of stimuli
at normal overall rates of presentation and attentional difficulty."
T.BATES (Univ. Auckland), 1995, from the abstract of an address
to International Society for the Study of Individual Differences,
meeting in Warsaw
FINIS
(Compiled by Chris Brand, Dept. Psychology, University
of Edinburgh.)
For more coverage of intelligence
and in particular 'inspection time, see:
BRAND, C.R. (1996) The g Factor.
Chichester : Wiley DePublisher.
"The nature and measurement of intelligence is a political
hot potato. But Brand in this extremely readable, wide-ranging
and up-to-date
book is not afraid to slaughter the shibboleths of modern "educationalists".
This short book provides a great deal for thought
and debate."
Professor Adrian Furnham, University College London.
The book was first issued, in February, but then withdrawn, in
April, by the 'publisher' because it was deemed to have infringed
modern canons of
'political correctness.'
It received a perfectly favourable review in Nature (May
2, 1996, p. 33).
For a Summary of the book, Newsletters concerning the
de-publication affair, details of how to see the book for scholarly
purposes, and others' comments and reviews,
see the Internet URL sites:
http://laboratory.psy.ed.ac.uk/DOCS/crb/internet.html
http://www.webcom.com/zurcher/thegfactor/index.html
For Chris Brand's 'Get Real About Race!'-his popular exposition
of his views on race and education in the Black
hip-hop music magazine 'downlow' (Autumn, 1996)-see:
http://www.bhs.mq.edu.au/~tbates/intelligence/Brand_downlow.html
A reminder of what is available in other Sections of
'P, B & S.'
Summary Index for PERSONALITY, BIOLOGY
& SOCIETY
(This resource manual of quotations about individual and group
differences, compiled by
Mr C. R. Brand, is kept on the Internet and in Edinburgh
University Psychology Department Library.)
Pages of Introduction
3 - 11 Full Index, indicating key questions in each
Section.
12 - 14 Preface. - Why quotations? - Explanations and apologies.
15 - 51 Introduction: Questions, Arguments and Agreements
in the study of Personality.
-Some history, and a discussion of 'realism vs 'idealism.'
52 - 57 Introductory Quotes about the study of personality.
Sections
General problems
1 'Situational' vs 'personological' approaches to
human variation.
2 'Nomothetic' vs 'idiographic', 'subjective' and relativistic
approaches.
3 Personality dimensions - by factor analysis and otherwise.
4 'Superstructure' and 'infrastructure' - the 'mind/body problem'.
5 Nature vs Nurture? - Or Nature via Nurture?
6 The role of consciousness in personality and 'multiple personality'.
7 The 'folk psychology' of personality components.
Intelligence
8 The measurement of intelligence. - Does g exist?
9 The bases of intelligence. - What is the psychology
of g?
10 The developmental origins of g differences. - The nature
and nurture of g.
11 The importance of intelligence. - The psychotelics
of g.
12 Piagetianism: Kant's last stand?
13 Cognitivism: 'The Emperor's New Mind?'
Propensities
14 Neurosis, emotion and Neuroticism.
15 Psychosis, psychopathy and Psychoticism.
16 Crime and criminality.
17 Genius and creativity.
Popular proposals - psychoanalytic, phrenological and prophylactic
18 Psychoanalysis: 'Decline and Fall of the Freudian Empire'?
19 Hemispherology: a twentieth-century phrenology?
20 Psycho-social Engineering: therapy, training or transformation?
Group differences
21 Age and ageing - especially, the role of g in 'life-span
development'.
22 Psychological sex differences. - Do they exist? Must they
exist?
23 Social class. - Does it matter any longer?
24 Racial and ethnic differences. - Their role in 'lifestyles'
and cultural attainments.
Ideological issues
25 The psychology of politics and ideological extremism.
26 The politics of psychologists and allied co-workers.
27 Equality and Community: the 'utopian' package of political
aims.
28 Freedom and Responsibility: the 'legitimist' package of political
aims.
Pragmatic questions
29 Carry on differentializing?
30 Carry on psycho-testing?
Appendix: Factor analysis. - 'Garbage in, garbage out'?
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