Memory is thought to be made up of 3 parts.
- Sensory Register (your senses)
- Short-term memory
- Long-term memory
In pyschology, definitions vary. Memory could be...
1. A cognitive process
2. A way of retaining information
3. A number of connected stores
4. Actual information retain.
Both short-term memory (STM) and Long-term memory (LTM) are studied in terms of their ability to encode (make sense of) information, capacity (how much information) and duration (how long information can be stored).
However, Reber (1985) thought that memory was possibly all of the above but in Pyschology, the deifnition of memory still remains elusive.
SHORT-TERM MEMORY (STM)
Encoding in short term memory
suggested that short-term memory codes all information acoustically, that is, according to sound. Visual information is encoded (transformed) to its acoustic (sound/language) codes.
Shulman (1970) disagreed and thought that short-term memory also coded information visually and according to semantics (meaning).
Heyer and Barrett (1974) suggested that visual images that are difficult to acoustically code may also be stored briefly in short term memory.
Research into encoding in short term memory - Conrad (1964)
Participants were presented with a list of consonants.
For example:P J N R Z D
for about ¾ of a second.
Participants were then asked to recall what they had seen.
Conrad found that errors of recall were linked to letters which had a similar sound.
Bs were mistaken for Ps 62 times, Vs were mistaken for Ps 83 times but Ss were mistaken for Ps only 2 times. This suggests that visually presented information is encoded according to acoustics/sounds. Conrad referred to these errors as Acoustic Confusion.
Research into encoding in short term memory - Shulman (1970)
This research suggests that Conrad was incorrect in proposing that all encoding in short term memory was acoustic.
Shulman presented participants visually with lists of 10 words. Recall was then tested using cue or probe words which were one of three types.
Firstly, some of the probe words used were homonyms (words which sound the same but have different meanings, for example: ball and bawl).
Secondly, some probe words were synonyms (different words with same/similar meaning, for example: talk and speak).
Thirdly some of the probe words used were identical to the ones on the original stimulus list.
Similar numbers of errors of recall from the stimulus list was made for homonym and synonym probes. This suggests that the semantic encoding (meaning) as well as acoustic encoding occurs in the short term memory.
Both the Conrad and Shulman research were laboratory experiments. They therefore lack ecological validity due to controlled artificial environments. Participants were undergraduate students and therefore unrepresentative of the general population. They may have exhibited demand characteristics and experimenter bias may have occurred as the experiment did not employ blind conditions.
The results may also have been influenced by individual differences or participant variables. The research has good reliability.
Capacity of short term memory
Capacity refers to the amount of information that can be…