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The key message about the brain is this: “The neurons that fire together wire
together” (Hebb, 1949). In Hebb's own words, from the Chapter 4 of the
Organization of Behavior, 1949: "When an axon of cell A is near enough to excite
B and repeatedly or persistently takes part in firing it, some growth process or
metabolic change takes place in one or both cells such that A's efficiency, as
one of the cells firing B, is increased" (p. 62).
Meaning that the more we repeat the same actions and
thoughts—the more we encourage the formation of certain connections and the more
fixed the neural circuits in the brain for that activity become.
“Use it or lose it” Is the corollary: if you don’t exercise brain circuits,
the connections will not be adaptive and will slowly weaken and could be lost.
(John Ratey M. D.
www.in.pi.cnr.it/images/ neurons.jpg
A Brain Based Explanation of Learning – Based on the
work of Elkhonon Goldberg The Executive Brain — Frontal Lobes and the
Civilized Mind
Although the signal generated within a neuron is electric, the communication
between neurons takes a chemical form
www.bris.ac.uk/.../2002/ images/er1.jpg
The signal called an action potential is generated within the body of a
neuron when it becomes stimulated
www.bbc.co.uk/.../humans/ nervoussystemrev2.shtml
The electrical impulse travels along an axon until it reaches the terminal,
the point of contact with a dendrite, which is a pathway leading to another
neuron. At the point of contact there is a gap called a synapse.
The arrival of the action potential (electrical impulse) releases a small
quality of chemical substances (neurotransmitters), which travel across the
synapse and attach themselves to the receptors, highly specialized molecules on
the other side of the gap.
www.chemsoc.org/.../2002/ gross_dec02_boxfig.gif
The neurotransmitters are then broken down in the synapse with the help of
special enzymes (or reabsorbed in some cases) and the process continues in this
way
www.chemsoc.org/.../2002/ gross_dec02_boxfig.gif
Through this process the brain can produce a virtually infinite array of
different activation patterns, corresponding to the virtually infinite states of
the outside world.
www.mikrowellenterror.de/ english/mw-weapon.htm
When an organism (a learner) is exposed to a new pattern of signals from the
outside world, the strengths of synaptic contacts (the ease of signal passage
between neurons) and local biochemical and electric properties gradually change
in complex distributed constellations
www.barclaycollege.edu/graphics/ 2002%20Havila...
This represents learning as we understand it today. |
Under Construction -- Watch for Updates