Awareness by wanghonghx

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									The Brain That Changes Itself

        Norman Doidge
• We see with our brains, not our eyes.
• Our eyes merely sense changes in light
  energy; it is our brains that perceive and
  hence see
• The brain is polysensory – its sensory areas
  are able to process signals from more than
  one sense
• Stages of learning are followed by periods of
  consolidation
• We have been given a brain that survives in a
  changing world by changing itself
• Tracing complex lines can improve children in
  all three areas – speaking, writing, reading
• Many children would benefit from a brain-
  area-based-assessment to identify their
  weakened functions and a program to
  strengthen them – a far more productive
  approach than tutoring that simply repeats a
  lesson and leads to endless frustration.
• The loss of drills such as rote memorization
  and handwriting has been costly; they may
  have been the only opportunity that many
  students had to systemically exercise the brain
  function that gives us fluency and grace with
  symbols
• The early years is when neuroplasticity is
  greatest
• Acetylcholine, a brain chemical essential for
  learning, is higher in rats trained on difficult
  spatial problems than in rats trained on
  simpler exercises
• Mental training or life in enriched
  environments increases brain weight by 5% in
  the cerebral cortex of animals
• Trained or stimulated neurons develop 25 %
  more branches and increase and increase
  their size, the number of connections per
  neuron, and their blood supply
• Postmortem examinations have shown that
  education increases the number of branches
  among neurons. An increased number of
  branches drives the neurons further apart,
  leading to an increase in the volume and the
  thickness of the brain.
• The idea that the brain is like a muscle that
  grows with exercise is not just a metaphor
• The brain is not an inanimate vessel that we
  fill; rather it is more like a living creature with
  an appetite, one that can grow and change
  with proper nourishment and exercise
• Second languages learned after the critical 0
  to 8 period are not procseed in the same part
  of the brain as is the native tongue
• The competitive nature of plasticity affects us
  all. If we stop exercising our mental skills, we
  do not just forget them; the brain map space
  for those skills is turned over to the skills we
  practise instead.
• As brain maps get bigger, the individual
  neurons get more efficient in 2 stages. At first,
  the map takes up more space. But after a
  while individual neurons within the map
  became more efficient, and eventually fewer
  neurons were required to perform the task
• A powerful signal has greater impact on the
  brain. When we want to remember s’thing we
  have heard we must hear it clearly,because a
  memory can be only as clear as its original
  signal
• Paying close attention is essential to long-term
  plastic change.In numerous experiments it has
  been found that lasting changes only occur
  when monkeys (in this case) paid close
  attention. When the animals performed tasks
  automatically without paying attention, they
  changes their brain maps, but the changes did
  not last.
• We often praise the ability to multitask. While
  you can learn when you divide your attention,
  divided attention doesn’t lead to abiding
  change in your brain maps
• ‘Rewards’ (eg a funny face on a screen) can be
  a crucial feature oflearning. Each time a child
  is ‘rewarded’, his/her brain secretes
  neurotransmitters such as dopamine and
  acetylcholine, which help consolidate the map
  changes just made.
• Dopamine reinforces the reward, and
  acetycholine helps the brain ‘tune in’ and
  sharpen memories
•
• When autism was first recognised about 40
  yrs ago (1965) about 1 in 5000 people had it.
  Now it is believed to be at least 15 in 5000.
• Even taking into account the increased
  diagnosis, it is about a threefold increase in 15
  yrs
• The nucleus can only be activated when
  something important, surprising or novel
  occurs, and if we make the effort to pay close
  attention
• In middle age, we still regard ourselves as
  active, but we have a tendency to deceive
  ourselves into thinking that we are learning as
  we were before.
• We rarely engage in tasks in which we must
  focus our attention as closely as we did when
  we were younger, trying to learn a new
  vocabulary or master new skills
• Such activities as reading the newspaper,
  practising a profession of many years, or
  speaking our own language are mostly the
  replay of mastered skills, not learning
• To keep the mind alive requires learning something
  truly NEW with intense focus
• However, you can’t improve a fading memory by
  asking people to do what they can’t. Instead,
  stimulate thru hearing / sight / tracing exercises
• Different chemistries are involved in learning than in
  unlearning. Unlearning and weakening connections
  between neurons is just as plastic a process, and just
  as important, as learning and strengthening them. If
  we only strengthened connections, our neuronal
  networks would get saturated. Evidence suggests
  that unlearning existing memories is necessary to
  make room for new memories in our networks.
• Massive neuronal reorganization occurs at two
  life stages: When we fall in love, and when we
  begin parenting
• It is the after-play, not the foreplay, that
  counts in building trust
• Can’t is a four letter word
• Based on work with plasticity, here are a
  number of ‘training’ principles:
  – Training is more effective if the skills closely
    relates to everyday life
  – Training should be done in increments
  – Work should be concentrated into a short time, a
    training technique Taub calls ‘massed practice’,
    which he has found far more effective than long-
    term but less frequent training
        (Taub, cited in Doidge 2008)
• Normally, when we make a mistake, 3 things
  happen. First, we get a ‘mistake’ feeling, that
  nagging sens that s’thing is wrong. Second, we
  become anxious, and that anxiety drives us to
  correct the mistake. Third, when we have
  corrected the mistake, an automatic gearshift
  in our brain allows us to move on to the next
  thought or action. Then both the ‘mistake
  feeling’ and the anxiety disappear.
• But, with OCDs, the automatic gearshift does
  not work.
• We don’t so much ‘break’ old habits as replace
  bad behaviours with new ones
• When you worry, relabel what is happening.
  You’re not experiencing an attack of germs of
  whatever, you ‘re experiencing an attack of
  worry
• With obsessions and compulsions, the more
  you do it, the more you want to do it. The less
  you do it, the less you want to do it
• It is not what you feel while applying the
  technique that counts; it is what you do. The
  struggle is not to make the feeling go away;
  the struggle is not to give in to the feeling
• Instead of plastic surgery, what people people
  sometimes need is neuroplastic surgery, in
  order to change their body image
• The brain can close a gate and block a pain
  signal by releasing endorphins, the narcotics
  made by the body to quell pain
• Experiment with 2 groups with electric piano.
  2 hrs /day over 5 days.One that physically
  practised; the other than imagined the
  practice.
• After 5 days, the same brain map
  improvement. First group were at Day 3 of the
  2nd group’s ability. However, after a single 2-hr
  practice, they were at the same standard
• Brain scans show that in action and
  imagination, many of the same parts of the
  brain are activated. That is why visualizing can
  improve performance.
• Experts don’t store the answers, but they do
  store key facts and strategies that help them
  get answers, and they have immediate access
  to them, as though they were in short-term
  memory
• This use of long-term memory for problem-
  solving is typical of experts in most fields.
• Becoming an expert in most fields usually
  takes about a decade of concentrated effort
• The system is plastic, not elastic. Elastic bands
  revert to their former structure after being
  stretched.
• In some cases, the faster you can imagine
  something, the faster you can do it.
• Eg handwriting. When you time how long it
  takes to imagine writing your name with your
  ‘good hand’, and then actually writing it, the
  times will be similar.
• When you imagine writing your name with
  your nondominant hand, it will take longer
  both to imagine and write it
• When we learn a skill during the day, we will
  be better at it the next day if we have a good
  night’s sleep.
• Early c’hood trauma causes massive plastic
  change in the hippocampus
• The longer people are depressed, the smaller
  their hippocampus gets
• Don’t get worked up about little things –
  stress releases glucocorticoids, which can kill
  cells in the hippocampus
• Neurogenesis – stem cells that continually
  rejuvenate all thru your life
• Mentally enriched mice have a 15% increase
  in the volume of their hippocampi, and 15%
  increase in number of neurons
• Massive pruning back in adolescence has its
  merits. Getting rid of extras keeps the brain
  more focused and efficient
• Many studies suggest that people wih more
  eduction seem better protected from mental
  decline
• Activities that involve genuine concentration
  are associated with a lower risk of dementia
• Age-related memory loss seems almost
  certainly reversible with the right mental
  exercises
• Physical exercise is important, because the
  brain needs oxygen
• Simply walking, at a good pace, stimulates the
  growth of new neurons
• Ages of 35 to 55 are the peak of creativity in
  most fields
• People in their 60s or 70s, although they work
  at a slower speed, are as productive as they
  were in their 20s
• Pablo Casals, the cellist, at 91, was asked:
  Master, why do you continue to practise?
  Because I am making progress
•   Four kinds of plasticity:
•   1. Map expansion
•   2. Sensory reassignment
•   3. Compensatory masquerade
•   4. Mirror region takeover
•   The left hemisphere normally acts like a bully,
    inhibiting and suppressing the right
•
• Easteners perceive holistically, viewing objects
  as they are related to each other or in context,
  whereas Westeners preceive them in
  isolation.
• In Korean school, 40% of primary school
  textbooks are devoted solely to Kim Jong

								
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