The Brain
Physiology and behavior:
Localization of function
• Explain one study related to localization of
function in the brain.
Explain one study related to
localization of function in the brain.
Studies
• Scoville and Milner
• Maguire et al.
Terms
• Phrenology
• Tan
• Broca’s Area
• Broca’s Aphasia
• HM
• Wernicke’s Aphasia
• Hippocamous
Early investigation of localization of
function
Phrenology
• The attempt to make
inferences about ones
personality and
intelligence by
examining skull
formation.
• Done by manually
searching for bumps
and indentations.
Franz Joseph Gall
In general….
• If there is a bump or
protrusion in that
area it indicates
MORE of that ability
or trait.
• If there is an
indentation it
indicates a
deficiency of that
ability or trait.
Phrenology?
• Do you think it is a valid
science?
• Work was picked up by
Cesare Lombroso
• These ideas, although
dangerous, are still the
basis behind modern
day criminal profiling.
Case studies of people with naturally
occurring brain damage
Phineas Gage
Paul Broca
• Worked with a patient
he called “Tan”
• “Tan” could only say the
word “Tan”
• “Tan” died
Broca’s Area
• In post-mortem
autopsy, Broca found
damage in the left
frontal area of Tan’s
brain.
• Broca discovered the
area of our brain that is
responsible for making
our mouth move during
speech.
Broca’s Aphasia
• Aphasia means damage
to a speech area of our
brain.
• Very common in TBI or
stroke patients.
Sarah Scott
Studies of individuals who have
undergone brain surgery
Damage to the hippocampus and memory
(The HM Study)
Scoville and Milner (1957)
• HM fell off his bicycle
when he was 7, injuring
his head.
• He began having
epileptic seizures when
he was 10.
• By the time he was 27
he had so many seizures
he could not live a
normal life.
The HM Study
Scoville and Milner (1957)
• Scoville performed
experimental surgery on
HM to stop the seizures.
• Seizures did stop, but
HM had amnesia for the
rest of his life.
• We learned a whole lot
from HM’s issues.
HM
• They removed parts of
his temporal lobe.
• They took out a little too
much and removed part
of his hippocampus.
• Experienced both
Retrograde and
Anterograde Amnesia.
Memories and the Hippocampus
Retrograde Amnesia
• Forget past.
• It can be time period, event
or select person.
Anterograde Amnesia
• Cannot form new
memories.
HM’s Memory
• He could not transfer new
episodic or semantic
memories (explicit
memories) into his LTM.
• He COULD form new
long-term procedural
memories (implicit
memories).
• He could carry on a
normal conversation
(working memory) but
would forget it almost
immediately.
OK…what actually happened to HM’s
brain?
• Corkin (1997) gave an
old HM an MRI
• He found missing parts
of the temporal lobes
and hippocampus and
surrounding areas.
• These areas tend to be
pathways for memory
(highways for ACH).
What can be learned about the relationship
between brain and memory with HM?
• Our memory system is
specialized and complex.
• The hippocampus plays a
critical role in converting
memories of experience
from STM to LTM.
• HM retained some
memories, so
hippocampus does not
store the memories, but
processes them.
Maguire et al. (2000)
• Aim: To investigate
whether or not the
hippocampus plays a
role in human spatial
memory
Maguire et al. (2000)
Method:
• London taxi drivers with a range
of age and experience were the
participants because their work
requires the extensive use of
spatial navigational skills
• Matched pairs design:
participants were age and gender
matched with a control group
• Two different types of MRI
scanning were used to assess
how the brains of the taxi drivers
differed from the control group
• Quasi experiment
Maguire et al. (2000)
• showed significantly
more grey matter in
both left and right
hippocampi of the taxi
drivers compared to the
control group
Maguire et al. (2000)
Evaluation:
• No ethical implications
• Only observed males
• Only observed 16
matched pairs
• Nature vs. Nurture
debate: did the driving
influence the change in
the hippocampus, or did
their larger than average
hippocampus lead them
to become taxi drivers?