Short Term Memory

In our normal life, we require much more than sensory register gives us in case of memory. Some memory holds information for fairly short intervals – say up to a minute and this is known as short term memory. It is also known as “Primary” or “Active memory”.

Capacity

The storage capacity of the STM is determined by the memory span, the number of items (either letter of words) one can recall just after one presentation visually or orally. Miller (1956) found the magical figure 7 ( plus or minus two) offers information for the power of short term memory. Most adults will keep between 5 and 9 items at their short-term storage.

Duration

Most of the information contained in short-term memory may be stored for about 20 to 30 seconds, but if rehearsal or active information maintenance is avoided, it could be only seconds. Information entering STM are forgotten quickly. One reason may be the decay, the memory trace may be eroded over time. Another reason may be interference, new items somehow may be pushed out of STM.

Some data will survive for up to a minute in short-term memory, but most information spontaneously decays very quickly.

How short term memory recall

How retrieval from STM takes place? In another word, suppose an item is still is short term memory, neither forgotten nor transferred to the LTM. How do we retrieve it? The answer is simple. The retrieval from STM is not instantaneous but requires some mental search and comparison. This may be done by parallel search, in which search is made and compared to each item in the memory set; or through serial search, in which comparisons occur successively.

How short term becomes long term memory

The retention of memories involves the transition of information from short-term stores into long-term memory because short-term memory is restricted in both ability and length. Exactly how did this take place? There are several different ways in which records can be committed to long-term memory, but the precise methods for moving memories from short-term to long-term stores remain.

Rehearsal

When preparing materials for an exam, you could use this method. Instead of only checking the data once or twice, before the essential information is committed to memory, you could go through the notes over and over again.

Exercise

The latest study has shown that exercise can also help to enhance short-term memory. One trial found that treadmill activity in Alzheimer’s rats leads to improvements in short-term memory by increasing neurogenesis, providing the potential for new ways to reduce any of the symptoms associated with Alzheimer’s disease.

The Atkinson shiffrin model

The classic model referred to as the Atkinson-Shiffrin or multi-modal model indicated that after a certain period of time, all short-term memories were naturally stored in long-term memory.