The Biology of Memory

What it comes down to is brain cells, or neurons, communicating with each other through electo-chemical pathways. An electrical impulse travels down the axon or "outgoing branch". Then the "fingers" at the end are stimulated to release chemicals called neurotransmitters (tiny molecules that send specific messages). The dendrites or "incoming branches" of other neurons pick these up. The space between the axon and dendrites is called a synapse.

 

For learning to "stick", the synapses need time to "gel". If the synapse doesn't "gel" then recreating the event, i.e. recalling the memory is difficult, if not impossible. A research team comprised of scientists from the University of Texas Medical School at Houston and the University of Houston reported the discovery of a new protein – transforming growth factor-B (TGF-B) that acts to solidify the new synapses (Science, March 1997). However, if there is too much protein it can build up and "clog" the synapse, thus reducing memory recall. Usually the neurotransmitter calpain, found in calcium, keeps the buildup of protein down. So, inadequate dietary calcium means that too much protein can build up because there is not enough calpain to keep the synapses clean. Unfortunately, an excess of calcium in the diet also creates a problem because the calpain starts to interfere with proper neural transmissions. A drastic way to remove excess protein from the synapse is by electric shock. Acetylcholine, one type of neurotransmitter, is important for three reasons: it is necessary for activating REM (rapid eye movement) sleep, it keeps neural membranes in tact so that they don't become brittle and fall away, and it breaks down the excess build up of amyloid protein at the synapses found in Alzheimer's patients (Robert Wurtham, director of the Clinical Research Center at Massachusetts Institute of Technology).

 

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