Memory may be defined as the processes by which information is encoded, stored and retrieved.
There are three basic stages of memory process. They are as follows:
- Encoding- Modifying information so that it can be placed in memory.
- Storing-Maintenance of information over time .
- Retrieval-The location of stored information and its return to consciousness.
Kinds of Memory:
Endel Tulvin,(1985,1991) classifies memory according to the kind of information they hold: Episodic, semantic, and procedural.
Episodic memory -Episodic memories are memories of the events that happen to a person or take place in his or her presence.
Semantic memory- General knowledge is referred to as semantic memory. Semantics concerns meanings.
Procedural memory- Procedural memory is also referred to as skill memory. It means knowing how to do things.
Iconic memory-Iconic memory refers to the sensory register that briefly holds mental representations of visual stimuli.
Echoic memory- It refers to the sensory register that briefly holds mental representations of auditory stimuli.
Information Processing Theory:
Humans process informations following the information processing model. Information processing model includes three main components- sensory memory, working memory and long term memory. Sensory and working memory enable people to manage limited amounts of incoming information during initial processing, whereas long-term memory serves as a permanent repository for knowledge.
Figure 3. The Information Processing Model of Memory (Based on Atkinson and Shiffrin, 1968)
[Ref. Stevens Handbook of Experimental Psychology (2002) 3rd Edition, Volume 2: ‘Memory and Cognitive Processes’. John Wiley & Sons, Inc.; pp 10].
This multi store memory model is later expanded upon by Baddeley and other co-workers and has become the dominant view in the field of working memory (Figure 4).[Ref. Stevens Handbook of Experimental Psychology (2002) 3rd Edition, Volume 2: ‘Memory and Cognitive Processes’. John Wiley & Sons, Inc.; pp 10].
Sensory Memory:
Sensory memory processes incoming sensory information for very brief periods of time.The amount of information held at any given moment in sensory memory is limited to 5-7 discrete elements such as letters of the alphabet or the digits. Thus, if a person viewed 10 letters simultaneously for one second, it is unlikely that more than 5-7 of those letters would be remembered. The main purpose of sensory memory is to screen incoming stimuli and process only those stimuli that are most relevant at the present time. Information that is highly relevant may receive some degree of controlled conscious processing. Controlled processing in sensory memory would be likely further to reduce the limited amount of information that can be processed at any given moment.
Working Memory:
After stimuli enter sensory memory, they are either forwarded to working memory or deleted from the system. Working memory is a term that is used to refer to a multi-component temporary memory system in which information is assigned meaning, linked to other information, and essential mental operations, such as inferences, are performed.
Figure 4 Baddley's working memory model
The original model of Baddeley & Hitch was composed of three main components; thecentral executive which acts as supervisory system and controls the flow of information from and to its slave systems: the phonological loop and the visuo-spatial sketchpad. The slave systems are short-term storage systems dedicated to a content domain (verbal and visuo-spatial, respectively). In 2000 Baddeley added a third slave system to his model, the episodic buffer. This component is a third slave system, dedicated to linking information across domains to form integrated units of visual, spatial, and verbal information with time sequencing (or chronological ordering), such as the memory of a story or a movie scene. The episodic buffer is also assumed to have links to long-term memory and semantical meaning.
Baddeley suggests that the central executive acts more like a system which controls attentional processes rather than as a memory store. This is unlike the phonological loop and the visuo-spatial sketch pad, which are specialized storage systems. The central executive enables the working memory system to selectively attend to some stimuli and ignore others. Baddeley (1986) uses the metaphor of a company boss to describe the way in which the central executive operates. The company boss makes decisions about which issues deserve attention and which should be ignored. They also select strategies for dealing with problems, but like any person in the company, the boss can only do a limited number of things at the same time. The boss of a company will collect information from a number of different sources.If we continue applying this metaphor, then we can see the central executive in working memory integrating (i.e. combining) information from two assistants (the phonological loop and the visuo-spatial sketch pad) and also drawing on information held in a large database (long-term memory). The central executive is the most important component of the model, although little is known about how it functions. It is responsible for monitoring and coordinating the operation of the slave systems (i.e. visuo-spatial sketch pad and phonological loop) and relates them to long term memory (LTM). The central executive decides which information is attended to and which parts of the working memory to send that information to be dealt with.
The phonological loop is assumed to be responsible for the manipulation of speech based information, whereas the visuo-spatial sketch pad is assumed to by responsible for manipulating visual images. The model proposes that every component of working memory has a limited capacity, and also that the components are relatively independent of each other.
Memory experiment
Rules for Non-Sense Syllables
1. Each syllable should consist of two consonants with a vowel in between.
2. Vowels in order: a, e, i, o, u, should not be used in this order.
3. The first and last consonant of same syllable or two consecutive syllable or first and last consonant of a syllable of list should never be the same.
4. Letters q, w, x, y, z should not be used.
5. H should not be used to end a syllable.
Syllables should be devoid of any association. C and K, G and J should not be used together in a syllable.
Rules for immediate memory span
1. Zero should not be used in a number.
2. No two consecutive numbers should be placed adjacent to each other.
3. There should not be repetition of any digit in a number.
4. There should be no arithmetic or geometric relationship between the numbers.
5. Inter-stimulus gap should be at least two seconds.
6. The digits should be read out in a monotonous tone at the rate of one digit per second.
Baddeley suggests that the central executive acts more like a system which controls attentional processes rather than as a memory store. This is unlike the phonological loop and the visuo-spatial sketch pad, which are specialized storage systems. The central executive enables the working memory system to selectively attend to some stimuli and ignore others. Baddeley (1986) uses the metaphor of a company boss to describe the way in which the central executive operates. The company boss makes decisions about which issues deserve attention and which should be ignored. They also select strategies for dealing with problems, but like any person in the company, the boss can only do a limited number of things at the same time. The boss of a company will collect information from a number of different sources.If we continue applying this metaphor, then we can see the central executive in working memory integrating (i.e. combining) information from two assistants (the phonological loop and the visuo-spatial sketch pad) and also drawing on information held in a large database (long-term memory). The central executive is the most important component of the model, although little is known about how it functions. It is responsible for monitoring and coordinating the operation of the slave systems (i.e. visuo-spatial sketch pad and phonological loop) and relates them to long term memory (LTM). The central executive decides which information is attended to and which parts of the working memory to send that information to be dealt with.
The phonological loop is assumed to be responsible for the manipulation of speech based information, whereas the visuo-spatial sketch pad is assumed to by responsible for manipulating visual images. The model proposes that every component of working memory has a limited capacity, and also that the components are relatively independent of each other.
The visuo-spatial sketch pad (inner eye) deals with visual and spatial information. Visual information refers to what things look like. It is likely that the visuo-spatial sketch pad plays an important role in helping us keep track of where we are in relation to other objects as we move through our environment (Baddeley, 1997).
As we move around, our position in relation to objects is constantly changing and it is important that we can update this information. For example, being aware of where we are in relation to desks, chairs and tables when we are walking around a classroom means that we don't bump into things too often!
The sketch pad also displays and manipulates visual and spatial information held in long-term memory. For example, the spatial layout of your house is held in LTM. Try answering this question: How many windows are there in the front of your house? You probably find yourself picturing the front of your house and counting the windows. An image has been retrieved from LTM and pictured on the sketch pad.
Evidence suggests that working memory uses two different systems for dealing with visual and verbal information. A visual processing task and a verbal processing task can be performed at the same time. It is more difficult to perform two visual tasks at the same time because they interfere with each other and performance is reduced. The same applies to performing two verbal tasks at the same time. This supports the view that the phonological loop and the sketch pad are separate systems within working memory.
Memory experiment
Rules for Non-Sense Syllables
1. Each syllable should consist of two consonants with a vowel in between.
2. Vowels in order: a, e, i, o, u, should not be used in this order.
3. The first and last consonant of same syllable or two consecutive syllable or first and last consonant of a syllable of list should never be the same.
4. Letters q, w, x, y, z should not be used.
5. H should not be used to end a syllable.
Syllables should be devoid of any association. C and K, G and J should not be used together in a syllable.
Rules for immediate memory span
1. Zero should not be used in a number.
2. No two consecutive numbers should be placed adjacent to each other.
3. There should not be repetition of any digit in a number.
4. There should be no arithmetic or geometric relationship between the numbers.
5. Inter-stimulus gap should be at least two seconds.
6. The digits should be read out in a monotonous tone at the rate of one digit per second.
No comments:
Post a Comment