| Title & Author | Abstract | |
|---|---|---|
| 10(002) | HUMAN EVOLUTION EXPANDED BRAINS TO INCREASE EXPERTISE CAPACITY, NOT IQ
Target Article on Brain-Expertise Dr. John R. Skoyles 6 Denning Road, Hampstead, London, NW3 1SU United Kingdom http://www.users.globalnet.co.uk/~skoyles/index.htm skoyles@globalnet.co.uk |
Abstract:
Why do modern humans have larger brains than earlier
people such as Homo erectus? As large brains cause problems in
childbirth, infancy and locomotion, the advantage they offer must
be substantial. This advantage might be associated with increased
IQ, but there is a problem: evidence from MRI volumetric surveys,
microcephaly and hemispherectomy shows that there exist individuals
with psychometrically normal IQ but Homo-erectus-sized brains. Why
did evolution increase brain size (with its associated costs) when
humans (as these individuals demonstrate) can have normal IQ
without bigger brains? I propose that the advantage may be related
to increased capacity for an aspect of intelligent behaviour not
measured by IQ tests but critical to the survival of our simple
hunter-gatherers ancestors: the capacity to develop expertise.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 10(011) | FACTUAL KNOWLEDGE AND PROBLEM-SOLVING ABILITY:
NOT EXPERTISE, BUT PERHAPS STILL RELATED TO BRAIN SIZE Commentary on Skoyles on Brain-Expertise Geir Overskeid Program in Economic and Organizational Psychology Norwegian School of Management BI P. O. Box 4636 Sofienberg 0506 OSLO NORWAY http://www.bi.no/users/fgl97015/index.htm geir.overskeid@bi.no |
Abstract:
Skoyles's claim that the large brains of modern humans
are related to our capacity for developing expertise seems well
founded. However, there are other possible candidates for this
role. I discuss two of them, problem-solving ability and the
ability to gather and remember large amounts of facts.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 10(012) | HUMAN EVOLUTION EXPANDED BRAINS TO INCREASE MOTIVATIONAL ABILITY,
NOT EXPERTISE CAPACITY Commentary on Skoyles on Brain-Expertise Pavel N. Prudkov Ecomon LTD Snezhnaya 14-2-18 129323 Moscow, Russia pnp@moneco.msk.ru |
Abstract:
Skoyles (1999) points out the paradoxical relationship
between brain size and intelligence, suggesting that evolution
expanded human brains to increase a hypothetical capacity to
develop expertise. We note a few weaknesses and inconsistencies in
the concept of expertise capacity and suggest that this concept is
very vague and needs further elaboration. Evolution expanded human
brains to provide the ability to construct and maintain social
motivations, a distinctively human property that underlies the
development of human civilization and culture. This ability can
explain the facts noted in Skoyles's target article and has new
implications for the relationship between brain size, intelligence
and motivation.
Keywords: Homo erectus, IQ, brain size, cortex, differences, evolution, expertise, frontal individual intelligence, language, social motivation |
| 10(024) | WHY HUMAN GRANDMOTHERS MAY NEED LARGE BRAINS
Commentary on Skoyles on Brain-Expertise Nicholas Humphrey Centre for Philosophy of the Natural and Social Sciences London School of Economics Houghton Street London, WC2A 2AE United Kingdom N.Humphrey@lse.ac.uk |
Abstract:
Skoyles's negative case that human brain size is
unrelated to IQ is strong, but his positive case that it is related
to expertise is weak. I propose that the explanation for the
evolutionary expansion of the human brain in fact lies far away, in
the need to have a brain that could continue to function into old
age.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 10(030) | HOW DOES BRAIN SIZE MATTER?
Commentary on Skoyles on Brain-Expertise David S. Webster Department of Psychology University of Durham Science Laboratories South Road Durham DH1 3LE Ken Richardson Centre for Human Development and Learning School of Education Open University Milton Keynes MK7 6AA D.S.Webster@durham.ac.uk & D.S. Webster@btinternet.com K.Richardson@open.ac.uk |
Abstract:
In this commentary on Skoyles we argue that the
distinction between expertise and IQ is not of the right kind to
explain the brain-size paradox. The evidence suggests that the
capacity for expertise has (a) a longer history than Skoyles would
allow; (b) is qualitatively related to increased brain
corticalization and restructuring with the emergence of H.
sapiens; (c) is developed against new demands made by a changing
ecology as a consequence of human global expansion, and (d) with
H. sapiens sapiens (i.e., Cro-Magnon and after), attains both
qualitative and quantitative independence from gross brain size.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 10(051) | EXPERTISE VS GENERAL PROBLEM SOLVING ABILITIES IN HUMAN EVOLUTION
Reply to Overskeid on Brain-Expertise John R. Skoyles 6 Denning Road, Hampstead, London, NW3 1SU United Kingdom http://www.users.globalnet.co.uk/~skoyles/index.html skoyles@bigfoot.com |
Abstract:
In my target article (Skoyle 1999) I proposed that
expertise, a domain dependent skill, was responsible for the near
doubling of brain size in hominid evolution. Overskeid (1999)
proposes instead that brain size is linked to two domain
independent cognitive skills: problem solving and factual
knowledge. My reply consists of two parts. First, I point out that
domain independent cognitive skills are the product of modern
education, technology, and culture, and hence irrelevant to
understanding the cognition and evolution of premodern people.
Second, I show that Overskeid's specific arguments against
expertise are limited, and argue that he fails to provide an
alternative.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 10(054) | THE EVOLUTIONARY PSYCHOLOGY OF PERFECTIONISM
Reply to Prudkov on Brain-Expertise John R. Skoyles 6 Denning Road, Hampstead, London, NW3 1SU United Kingdom http://www.users.globalnet.co.uk/~skoyles/index.html skoyles@bigfoot.com |
Abstract:
Prudkov (1999) suggests an alternative to my proposal
(Skoyles, 1999a) that the near doubling of human brain size since
Homo erectus arose to increase our capacity for expertise. His
criticism is that long term motivations are needed for the
acquisition of expertise. Prudkov has identified a weakness in the
present literature in the subfield that studies expertise: what is
the nature and origin of the motivation -- perfectionism -- that
leads people to engage in the prolonged practice needed to become
experts? I show that this motivation is peculiar, species-specific
and appears to be central to human evolution. However, it
complements rather than replaces (as suggested by Prudkov) the role
of expertise in the evolutionary near doubling of human brain
size.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 10(055) | WHY HUMAN GRANDMOTHERS MAY NOT HAVE NEEDED LARGE BRAINS
Reply to Humphrey on Skoyles on Brain-Expertise. John R. Skoyles 6 Denning Road, Hampstead, London, NW3 1SU United Kingdom http://www.users.globalnet.co.uk/~skoyles/index.html skoyles@bigfoot.com |
Abstract:
Humphrey's grandmother/redundancy hypothesis could be
strengthened; it has problems which indicate that the expertise
capacity hypothesis offers a better explanation for the expansion
of human brain size. Only research upon microcephalics and others
with Homo erectus sized brains and normal IQ can enable us to
determine what factor in human evolution led to our enlarged
brains.
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |
| 11(056) | BRAIN SIZE DOES MATTER
Reply to Webster on Skoyles on Brain-Expertise John R. Skoyles 6 Denning Road, Hampstead, London, NW3 1SU United Kingdom http://www.users.globalnet.co.uk/~skoyles/index.html skoyles@bigfoot.com |
Abstract:
Webster & Richardson's (1999) work on covariation and
co-ordinate hyperstructural information merits wide discussion,
however, it has little to do with my target article (Skoyles,
1999).
Keywords: brain size, brain imaging, evolution, expertise, hemispherectomy, Homo erectus, individual differences, intelligence, IQ, language, microcephaly, MRI volumetrics, psychometrics. |