How many types of memory exist?

As memory is not the simple cogitative function, representation about it as about the difficult phenomenon consisting of 3 big subsystems will be more adequate: touch memory, short-term and long-term memory. They function as original storehouses in which there is an information. These above-stated subsystems differ with quantity stored information and time of its storage.

Touch memory

It - storehouse in which the information directly received from sense organs is embodied. The stimulus which arrives to touch memory, is not exposed to the analysis and is not interpreted at all, it remains during very short period of time, only about 250 milliseconds, as purely touch stimulation, as well as in a resonance box though during that moment to it it is not given great value.

The Melody of touch memory

If someone, listening to the jazz melody transferred by a musical radio channel, suddenly will switch off a sound, within several instants he can hear saxophone sounds. They will sound in our touch memory. Function of this information storehouse consists in prolongation of duration of stimulation for increase of our ability to analyze and use the received information.

Similar occurs, for example, during conversation when one of the speaking realises, that badly heard last statement of the interlocutor, however then when he asks it to repeat, he appears to reconstruct the passed phrase in a condition. This results from the fact that there was a reference to touch storehouse which has kept the information already embodied earlier by sense organs.

Fragility of deduction

Touch memory is limited enough, it keeps the information during very short period of time and, besides it, it is very sensitive to various hindrances. Any derivation of the attention, whatever minimum it was, can erase information just received from sense organs, and nothing can prevent it. From 3 systems of memory touch memory is capable to embody the minimum volume of the information in the minimum time interval. Though till now researchers mentioned only storehouses of the visual and sound information, it is logical to think, that any version of touch memory has own storehouse of the information.

Short-term memory

This kind of memory is considered system to which posesses more active role in cerebration. Duration of its action - average and though possibilities of short-term memory are limited, they exceed possibilities of touch memory. Short-term memory keeps the information which has arrived from touch storehouse, during time, sufficient for its use by other informative systems. The data registered by short-term memory, are forgotten, at least, in 30 seconds. In the most widespread way, its mental repetition 1 or 2 times is applied to avoid information disappearance. Short-term memory is the basic process for maintenance of activity of other kinds of memory.


If we wish to remember a phone number from the telephone directory we will repeat it until it will not be fixed in memory. After phone call realisation, we, probably, will forget it.

Someone will repeat in the same way about itself (himself) a combination of figures of licence plate of the car on which criminals have disappeared from a scene of crime which witness it was and which wishes to declare in police. If you do not want, that the slightest accident promoted information loss it is necessary to repeat number until can write down it on a sheet of paper.


Intellectual pressure or short duration of action are not the unique restrictions peculiar to short-term memory. There is also a limit of abilities. In a quiet condition some people are capable to remember to 5 elements, others - to 10, however at the majority this quantity is limited to number «7". This phenomenon has received the name «magic number Miller», in honour of George Miller who has opened him. This formula does really «magic» the following fact: 6 elements or the remembered groups can correspond to blocks of the different information. So, when someone is put on trial in which course he should repeat immediately a series of elements, it remembers the same number of elements irrespective of, they consist of letters, syllables

or words; that is, the person remembers and reproduces about 7 elements of the information. As though short-term memory was the playing device for which reduction in action it is necessary to lower coins and on which there would be 7 cuts for them Though during each game it is possible to do rates with coins of different advantage, you never can stake more than 7 coins simultaneously. Hence, we face system of the limited capacity and short duration of action which demands applying of additional efforts for information storage in an active condition. Thus the system of short-term memory should not be considered only as storehouse for a long finding of the information which have arrived from touch memory.

Operative or working memory

The System of short-term memory also functions as original working memory which allows to supervise over simultaneous realisation of several kinds of cerebration. Think of how to divide in mind 212 on 40. In the beginning it is necessary to divide figures, to see the multiplication table, to find approximate value, to subtract it from a dividend and so on, before operation end. Not to lose a thread of calculations, it is necessary to remember the information on each intermediate step. Time storage of intermediate results is made in system of short-term memory. In the same way viewing of results of the multiplication table which are in long-term memory, also occurs in operative memory. Hence, short-term memory - it is system which is used for deduction of earlier data received from touch and long-term memory. The operative aspect of short-term storage allows to support in an active condition the data necessary for the decision of problems of training, understanding and a logic reasoning. Through operative memory access is provided to storehouse of long-term memory, data practically activity any kind. It becomes at attempts of the person to understand a word meaning which he hears, the maintenance of books which he reads, at movement on a city, at memoirs on own actions, at preservation of skills of the training, the received experience and, at last, own existence.

Long-term memory

It - an encyclopaedia version in which there is all information, not now in use to which it is possible to address at any moment. Corresponds to the general representation about memory, as about stable storehouse in which everyday experience of human activity collects. The information is stored more or in less stable image, ability of its storage virtually is not limited. Time during which data can be at the disposal of long-term memory, varies from several minutes till several years.

All necessary for coexistence

In long-term memory are the storehouses filled with the most different information: skills of understanding of speech, knowledge of laws of physics, personal knowledge of people, of how to behave in certain social situations how to sit down on a bicycle , to float etc. Actually if the person did not possess similar storehouse with possibility of constant access to the information, its experience would not be continuous for a long time. Training any kind would appear useless, we could not take advantage of the experience, would not have the friends, the impossibility to learn each other would become one of probable consequences. We would not know neither about the past, nor about own actions, about how could achieve the purposes.

Subsystems of long-term memory

All variety of details which can be found out in long-term memory, is grouped round 3 subsystems: procedural memory, semantic memory and incidental memory.

- Procedural memory. Unites the details, concerning a way of realisation of any action. Contains a considerable quantity of motor skills, such as ability to sit down on a bicycle or to drive the car. However, besides these abilities, procedural memory contains a considerable quantity of other, diversified skills: from application of electrical household appliances to instructions for use the personal computer or sequences of the decision of the mathematical equation, based on the automated skills.

  • Semantic memory. Contains the information uniting our knowledge of the world. Basically - About events, ideas and terminology. In this subsystem there are data about historical events which have been studied at school, dates of days of births of our friends or data on a word meaning.
  • Incidental memory. Stores temporary exiles on events of our private life. Events of such emotional life experience as the first appointment, or memoirs on a place where the poem, or on time period when have decided to be equipped in own house has been learnt by heart, are grouped in incidental memory. In the same place It is possible to find the information that we did in the last summer where had supper yesterday and where we park our car. Some of these events are stored in our memory long enough time while others are forgotten soon after their fulfilment. Probably, certain important data, and also the most typical or exciting experience are kept in memory. So, we cannot recollect, that on Monday last week houses had supper and, on the contrary, with sufficient accuracy we recollect a certain special supper.