Transcript How Do We Learn? - Carson

What Can Brain Research Tell
Us About How We Learn?
Mary Ball
Fall 2007
Early Brain Studies
Studies of People After Brain Surgery or Brain
Injuries (e.g. Henry M.)
 Post-Mortem Examination of Brains and Brain
Tissue (e.g. Alzheimer’s Disease)
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Basic Brain Structure
Composed of Neurons and supporting cells
 Myelinated axons appear white (hence
called White Matter)
 Unmyelinated tissue appears grey (hence
called Grey Matter)
 Neurons form “circuits” via Dendrites and
Axons
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Basic Neuron Structure
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Source: NIH Publication No.02-3440d
The Visible Human Project
In 1994 and 1995, two cadavers were
frozen in gelatin.
 Starting at the head end, the block of
frozen material was slowly ground down
smooth and photos of the surface were
repeatedly taken.
 Photos were taken every mm for the male
and every 1/3 mm for the female.
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Whisker Removal in Mice Leads to
“Dendritic Spine Sprouting” (2002)
In 1962, researchers reported evidence of limited
neurogenesis in rats following brain damage.
In 1998, researchers reported neurogenesis in
the adult human hippocampus.
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Immunofluorescence for neurons (a), new cells
(b), and glial cells (c) indicated the new cells
were neurons!
Tool
How It Works
PET Scan
Detects active regions of the brain by
tracing radioactive isotopes.
fMRI Scan
Detects active regions of the brain by
visualizing where oxygen is being used.
qEEG
Detects active regions in the brain by
electrical activity (brain waves).
MRI Scan
Distinguishes gray matter, white matter,
and ventricles.
Voxel-based Statistical procedure to measure average
Morphometry volume of a specific region of the brain.
Brain Structures Differ between Musicians
and Non-Musicians (2003)
Gray matter increased in students
learning to juggle. (2004)
Summary of What the Researchers
Already Knew
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The human hippocampi are important in longterm memory.
Neurogenesis is possible in the hippocampi in
adults.
Dentritic growth and spine sprouting have been
directly observed in mice adjusting to change.
Voxel-Based Morphometry can be used to detect
changes in gray matter volume over time and/or
between groups.
Learning to juggle resulted in transient increases
in gray matter in a sample of young adults.