PSYC 333 Lecture Notes - Lecture 13: White Matter, Standard Deviation, Haier
7 May 2018
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March 2nd:
• Today’s class is about the brain differences related to intelligence, if there are
any
• We didn’t always think the brain was where intelligence was held, once
though it was the heart
• Is brain size related to IQ?
o Modest correlation IF you control for body size (ex: children)
o Endocasts used to be done to assess brain size (but it just looks at the
size of the head, not related to grey matter -> hydrocephalia means
head is filled with fluid so it gets bigger but brain is not larger)
o Phrenology: looking at the size of the head. Bumps = fortes in certain
things, crevices = weaknesses in certain things.
o We’re in the neuro-everything phase of history! We can look at the
person’s brain without them being dead. 0. correlation between
brain size and IQ, correlation higher in females.
▪ Make sure to research whether the study is looking at white
matter, grey matter, or something else
▪ Grey matter higher corr in men, white matter higher corr in
women
▪ Newest corr is 0.4. A lot of these studies try to compare men
and women so be careful what they’re comparing.
o Larger brain size = more neurons?
o DTI is the funky picture at the bottom right, maps white matter fibers
(axons). Myelination = white matter
• Regions:
o Positive correlation between IQ and brain matter in: PFC, Parietal,
Occipital and Cerebellum (LATTER IS VERY IMPORTANT IN IQ!! We
didn’t think so before, though it was just for motor movements)
o Good authors for this: Richard Haier, Cabeza (lol)
o Localization theory: every region of the brain does a different thing.
Anti-localization: different areas do the same thing, all kinda work
together. Hybrid model: there is some specialization but also shared
tasks.
o Researcher worked on pigeons, took out 90% of brain matter and saw
pigeons still functioned properly. Super wrong – he probably just took
out certain areas, plus those areas STILL MEANT SOMETHING.
o Sometimes people can function without a big chunk though! Seizures
patients may lose half their brains.
o Lesions:
▪ What we worked on before neuroimaging
▪ Ex: Phineas Gage
▪ Right after injury people may struggle with working memory,
executive functioning, Gf. Highlights importance of PFC in intel.
find more resources at oneclass.com
find more resources at oneclass.com
▪ But, eventually they compensate! So was that region all the
important?
• Jung and Haier (2007):
o Reviewed 37 studies
o Some areas are constantly activated when doing intelligent
behaviour/intelligence tests: frontal lobes, parietal lobes, white
matter tracks connecting all the regions! (arcuate fasciculus)
o 2 people can activate different areas in order to achieve the same task,
have the same intelligent behaviour!
o People vary in grey matter in the important areas used to produce
smart behaviour. People vary in grey matter within this system; this
is how we explain strengths and weaknesses in people (ex: I’m good
at Raven’s but not verbal tests)
▪ But, the IQ tests do somewhat correlate with each other, is that
general intelligence, speed of processing, working memory?
o Haier and Jung probably strongly believe in the model that grey
matter is related to IQ
• Do smarter people having less activation in certain tasks mean they are more
neutrally efficient? Another theory
o Brain is 2% of body weight but 20% O2 and 25% glucose -> very
expensive
o Brain efficiency theory: not only how hard you can work, but how
efficiently you can work.
o Haier 1988 famous study:
▪ 2 people who did Ravens, scored 11 and 33 (maximum)
respectively, and 33 had much less activation/glucose
consumption!
o Tetris study 1992:
▪ Smartest participants more efficient after practice (50 days
of training in Tetris)!
▪ Used Raven’s and WAIS to test intelligence
▪ Many studies have replicated this decreased activation with
practice
o Greek (!!) study:
▪ Common design: Put people in a brain-imaging device and
asked them to close their eyes and do nothing. Resting state.
▪ In this study, he participants were watching TV (not totally
resting).
▪ High IQ people have a different resting state! The brain never
really disengages, always active!
Autism and Intelligence guest lecture:
• Neuropsychologist studying autism and intelligence for 20 years, works as a
clinician and researcher
• Intelligence and reasoning development in autistic children, particularly
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
March 2nd: today"s class is about the brain differences related to intelligence, if there are, we didn"t always think the brain was where intelligence was held, once though it was the heart. Bumps = fortes in certain: we"re in the neuro-everything phase of history! We can look at the person"s brain without them being dead. Occipital and cerebellum (latter is very important in iq!! We: positive correlation between iq and brain matter in: pfc, parietal, newest corr is 0. 4. Anti-localization: different areas do the same thing, all kinda work together. Seizures patients may lose half their brains: lesions, what we worked on before neuroimaging, ex: phineas gage, right after injury people may struggle with working memory, executive functioning, gf. Highlights importance of pfc in intel: but, eventually they compensate! In this study, he participants were watching tv (not totally resting): high iq people have a different resting state!
