Page 63 - 84 human physiolofy part-1

The Nervous System

1. Sensory Memory
2. Short Term Memory
3. Long Term Memory

Sensory Memory
The sensory memories act as a buffer for stimuli through senses. A sensory memory retains an
exact copy of what is seen or heard: iconic memory for visual, echoic memory for aural and
haptic memory for touch. Information is passed from sensory memory into short term memory.
Some believe it lasts only 300 milliseconds, it has unlimited capacity. Selective attention
determines what information moves from sensory memory to short term memory.

Short Term Memory
Short Term Memory acts as a scratch pad for temporary recall of the information under process.
For instance, in order to understand this sentence you need to hold in your mind the beginning of
the sentence as you read the rest. Short term memory decays rapidly and also has a limited
capacity. Chunking of information can lead to an increase in the short term memory capacity, this
is the reason why a hyphenated phone number is easier to remember than a single long number.
The successful formation of a chunk is known as closure. Interference often causes disturbance in
short term memory retention. This accounts for the desire to complete a task held in short term
memory as soon as possible.

Within short term memory there are three basic operations:

1. Iconic memory - the ability to hold visual images
2. Acoustic memory - the ability to hold sounds. Can be held longer than iconic.
3. Working memory - an active process to keep it until it is put to use. Note that the goal is not
really to move the information from short term memory to long term memory, but merely to put
it to immediate use.

The process of transferring information from short term to long term memory involves the
encoding or consolidation of information. This is not a function of time, that is, the longer the memory
stays in the short term the more likely it is to be placed in the long term memory. On organizing
complex information in short term before it can be encoded into the long term memory, in this process
the meaningfulness or emotional content of an item may play a greater role in its retention in the long
term memory. The limbic system sets up local reverberating circuits such as the Papaz's Circuit.

Long Term Memory

Long Term Memory is used for storage of information over a long time. Information from short
to long term memory is transferred after a short period. Unlike short term memory, long term
memory has little decay. Long term potential is an enhanced response at the synapse within the
hippocampus. It is essential to memory storage. The limbic system isn't directly involved in long
term memory necessarily but it selects them from short term memory, consolidates these
memories by playing them like a continuous tape, and involves the hippocampus and amygdala.

There are two types of long term memory:

1. Episodic Memory

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