Brain plasticity dimensions of learning and education Michael M. Merzenich, Ph.D.

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Oregon State University
Corvallis OR
May 1, 2009
Brain plasticity dimensions
of learning and education
Michael M. Merzenich, Ph.D.
Professor Emeritus
University of California at San Francisco
Chief Scientific Officer
Posit Science Corporation (San Francisco)
Scientific Learning Corporation (Oakland)
Brain plasticity…..
….. a powerful,
under-utilized,
life-long
personal
resource
Epoch 1: YOU began to create yourSELF in an
early “critical period” of brain development.
The brain’s task:
1. to create a
model of the
world into which
it just happens
to have been
born; and
2. to learn how to
control the
actions required
to survive/thrive
in that world.
Epoch 2: An older brain CONTROLS its
own plasticity, as it masters skill after skill.
7 tenets of “adult” cortical plasticity
1.
2.
3.
4.
5.
6.
7.
Plasticity occurs ONLY when the brain is in the mood for change.
WHAT changes are the strengths of connections (synapses) for
inputs that are excited together, for each successive moment, in
time.
The connections of between sources of activity that regularly occur
NEXT to one another in serial time are also selectively strengthened.
Initial changes are temporary. If the brain judges the experience to
be inherently fascinating or novel, or if the behavioral outcome is a
good (or bad) one, they THEN become permanent.
The harder we try, the more we are motivated, the more alert we are,
and the better (worse) the outcome, the GREATER the brain change.
MEMORY is crucial for learning.
Brain plasticity is a two-way (REVERSIBLE) street. It is just as easy
(and natural) to generate negative changes as it is to generate
positive changes.
Progressive experience-/learning-induced
plasticity has created…………….
YOU
Billions of learned associations between a growing
“self” and ITS unique world underlie its genesis -and its continuous, inexorable revision.
Overcoming developmental impairments as juveniles/adults
Training-induced
recovery from
‘negative’
plastic changes
arising from
abnormal
development,
or from changes
in normal aging.
What developmental deficits (not directly attributable
to inherited faults) are NOT ‘correctible’?
Zhou, Merzenich et al, 2008a, PNAS; also
see Bao, Merzenich et al, 2004, PNAS;
Zhou & Merzenich, Nat Neurosci 2008
Rat Rehab
Overcoming age-related functional losses
At least most
physical and
functional
limitations
arising through
the course of
normal aging
are correctible
(reversible).
Many positive brain changes result from training
a) Sharp and strong
brain representations
– rain ACCURACY -- is
restored.
b) Brain SPEED is
restored.
c) INHIBITORY POWER &
SELECTIVITY are
restored.
e) LEARNING rates are
restored.
g) Trophic factors
supporting PHYSICAL
BRAIN HEALTH are
restored.
i) MEMORY is
recovered.
j) NOISE IMMUNITY is
restored.
k) Important PHYSICAL
CHANGES are
overcome.
k) INDEPENDENCE &
LONGEVITY are
extended.
YOUNG
OLD
OLD,
TRAINED
A question: What is NOT reversible?
Crucial steps toward developing training strategies
for neurological ‘improvement’ or ‘correction’
A) To determine the neurological origins of
behavioral deficits …….
And with that understanding,
B) To develop brain plasticity-based strategies
designed --- to the extent possible --- to overcome
them.
Our primary targets:
Struggling school-aged children
Functional loss in normal aging
Pathological aging (MCI; Alzheimers)
Psychotic illness (schizophrenia; bipolar
disorder, depression; anxiety; et alia)
Brain infections and other causes of diffuse
brain trauma
Traumatic brain injury, stroke
Acquired movement disorders (e.g. Parkinsons)
1.
2.
3.
4.
5.
6.
Summarizing impacts from child training:
1.5+ million children have been trained
Focus on language, reading, cognition
Approximately 15-17 total hours of
training/module (e.g., Fast ForWord LTP)
Scientifically documented benefits
The state achievement test scores for most
kids move, relative to other kids in their
school or state.
(see www.scientificlearning.com)
Training changes brains.
To hear more about this subject, tune in to “The New
Science of Learning. Brain Fitness for Kids” – to be aired
over the next several weeks on most national PBS stations.
Cases (ordered by chronological age)
TOLD Language Age I:2 & P:2 combined
Pre- to Post-Training Change (n=96)
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• = Chronological
age of each child
11
Language Age (years)
12
13
TOLD Quotients (I:2 & P:2 combined)
Pre- vs. Post-Training Scores
BELOW AVERAGE
AVERAGE
Median
SPOKEN
LANGUAGE
Listening
Speaking
Pre-Training
Semantics
Post-Training
Syntax
Phonology
80
85
90
95
100
Quotient Value
105
110
Reading achievement and Fast ForWord in a Texas
school district (Gates-MacGinitie test)
Participant Group
(Fast ForWord)
Comparison Group
(No Fast ForWord)
6.0
5.5
Grade Equivalent
Reading gains
are enabled by
listening
training.
5.0
4.5
4.0
3.5
3.0
0.5
0.0
Reading
Before
After
8 - 12 Weeks After
Mean Grade Level
Neurological impacts (reading)
Brain Areas
Critical For
Reading
Normal reader
Dyslexic, before training
Dyslexic, after training
Similar neurological corrections are recorded for
language, memory, attentional and other abilities.
Temple et al., PNAS 2003; Raab, Temple et al., 2008
Is it possible to improve the brain-power for the
young people in your classrooms?
“Normal Adults”: “Users” of mastered (automatic) skills
and abilities.
‘Healthy’ people on the decline (probably) just like you!
Age-Related Cognitive Decline---A pervasive feature of aging
Effect of Age on Various Aspects of Mental Function
Z-score for composite
“professionals”
Affects virtually all
mental abilities
1
knowledge
.5
Begins in the 20’s
& 30’s; continues
throughout life
0
accuracy,
speed,
memory
reasoning
fluency……..et alia
-.5
-1
-1.5
20
40
60
80
Chronological age
Adapted from studies conducted by University of Virginia professor Timothy Salthouse.
People in their
70’s are in the
bottom 20%,
relative to people
in their 20’s
In aural speech, & language,
older individuals have
• Degraded receptive abilities
– accuracy
– at speed
• Degraded aural speech memory
• Low ‘processing efficiency’
• Decline in verbal accuracy, fluency
Special problems apply for vision – e.g., the
reduction of your “useful field of view”
When we’re young, we have an ear-to-ear
view of the world, in high-definition…
Alas, when we’re older……
What accounts for these changes in your
abilities as you grow older?
Why do we lose it?
We don’t “practice” enough (or in the right ways)…
… and we have inadequate schedules of NEW learning.
Any (every) brain can be strengthened
(protected from loss) at any age.
Documented gains achieved with
training at the ‘brain gym’:
Brain ‘speed’
listening 2x
vision 2x
everyday skills 2x
efficiency, fluency
Automobile driving
frequency/distances
confidence
license retention
Automobile driving safety
Memory/cognition
listening, language
vision
11+yrs Learning rates
Attentional/executive control
Health
physical
mental
Maintained independence
Longevity
See www.positscience.com for scientific references
What else could/should you be doing, to
assure better brain health at an older age?
1.
Challenging, continual new skill learning
2.
Re-engage with the details of your world (your
‘senses’).
3.
Adopt a regular regimen of physical exercise/
activity.
4.
Feed your brain & body with what they require to
sustain their health & vigor.
5.
GROW the person that you are (with a steady diet of
new experiences, and through continuing education
--- ala KQED).
For more information:
See www.PositScience.com and
www.brainconnection.com for more information
about this science or these training programs.
See my blog site (www.onthebrain.com) for more
information about the application of brain
plasticity science to address human problems –
and for a consideration of the societal
implications of brain plasticity science -discussed from my personal perspective.
Please contact me (merz@phy.ucsf.edu) if you
have questions.
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