Memory

What do americans think about their memory?
Well, according to several surveys conducted in
the fall of 2006 - we believe our memory sucks. Why?
Good question. Most of us think it is probably a consequence
of all these memory aiding applications: cell phones, palms,
laptops and other hi-tech gadgetry.

A large body of research gatherd throughout the past
3 years show that this may very well be the case. As
technology usage increases, we become less and less
dependant on our biological memory, gradually causing
our memory to deteriorate. The brain thrives when used
repetedly. Not using it enough can cause a profound decrement
in our cognitive abilities overall: Memory impairment,
decrease in verbal flunency, decreasment in thinking speed
and many other mental skills.

The Memory is a neural activity, involving many
different areas and processes inside the brain.
Memory is often described as "a process of data
retention in which our experiences are stored, sorted
and later recovered by will".


Short-term Memory
Neurologists divide memory into long-term and
short-term memory, or "working" memory. Short-term
memory, or STM, is the brain's mechanism for remembering
information "in use". Most people can only hold
five to nine items in their short-term memory at once.
STM works like this: First, "the brain's cerebral
cortex receives nerve messages from eyes, ears, and
touch sensors. This sensory stimulus is held for
a fraction of a second in the sensory memory. Unless an
effort is made to encode the stimulus into STM, it will
be lost and gone. Shortly after the memory is stored
two things can happen to the information: either furtherly
processed as long-term memory or lost (forgotten).


Long Term Memory
Long-term memory, or LTM, is a componant of our memory
storage mechanism that has infinit capacity to retain
data, as long as sufficient amounts of time are given for
neurological assimilation. At least three different types
of memory are included in what we call "LTM":
Procedural memory represents motor or skill learning
which is memory without verbal mediation and thus without
record. It includes learning how to ride a bicycle or tool
usage. Such memories are slow to acquire but very resistant
to change.
Declarative memory is the memory for facts, such as
names or dates. It is fairly unstable since the information
activates the receptors (within the synapse) without being
retained via LTP process.
Remote memory Refers to memories that were acquired
early in life. They represent the infrastructure upon which
newer memories are linked and stored. This type of memory is
considered to be relatively stable.


LTM Anatomy
Both STM and LTM are composed of three processes:
encoding, storage, and retrieval. These processes
take place in various areas of the brain.
Scientists now know that the hippocampus is involved
in the process of long-term memory. Research implies
that every single memory can be broken down into several
elements and stored in many locations at once. They seem
to be stored through circuitry. In addition, different kinds
of memories are stored in different areas: Reflexive
memory is a product of the cerebellum and amygdala;
formative memory is produced by the hippocampus and
thr temporal lobes.

The Prefrontal Cortex
The prefrontal cortex, located in the forehead area of
the brain, is heavily involved in working memory (STM).
Experiments using PET scans and fMRI show that the
prefrontal cortex is consistently active when specific
data is being processed.

Up-to-Date Research
Short-term memory is believed to be formed by brief
changes in synaptic transmissions, or by reverberating
feedback circuit, where a memory is held electrically
within a loop. Long term memory, is encoded
by plastic changes in existing synapses, a process
also called "Long Term Potentiation", or LTP.




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