Definition, process and stages
The definition of Memory is the processs by whcih we ratain information about events that have happened in the past.
The process is;
Encoding- changing information into a code to be stored
Storage- Information is stored in the memory
Retrevial- Is recalling the information stored
Sensory is where the information is held in a unprocessed form
Short term is where the information is stored for a short period of time
Long term is that it holds a lot of data for long periods of time
Multi Store model
It was created my Atkinson and Shiffrin 1968
The first part to the multi store model
Incoming stimuli moving into the sensory store, with paying attention is moves on to the short term memory store which has a rehearsal loop before it moves on to the long term memory store then with retreival it can go back into the short term memory store,
Strength of this is that it shows the different stores for each section and has research evience to support it.
Glanzer and Cunitz
Showed that people rememeber things they have seen first and last, first goes into long term memory and last goes into short term memory have difficulty remembering inbetween.
A weakness of it is that it is seen as being too simplistic
Working Memory Model
This model was by baddeley and Hitch 1974
There is 3 main parts to this model;
The Central Excecutive where the brain pays attention to the information, The Visuo-spatial scratch pad where the mind takes in the visual parts of the information, and the Phonological loop this is where the memory takes in the sounds of things. From the Visuo-spatial scratch pad and the phonoligal loop the inofmration moves on to the long term memory
A strenght of this model is that it shows that the short term memory can do 2 things at once unlike the multi store model who says it can only do one.
Weakness is that does know explain enough on the most important part of the process Central Executive
Robbins Et all 1996 did a study to show the importance of the central executive.
Short term memory studies
There are three things that have been tested for short term and long term memory they are, Duration, Capacity and Encoding.
Duration was done my Peterson and Peterson in 1959, There aim was to see how long their short term memory could remember something without rehearsel. They got shown trigrams for example TRP, asked to count back in 3s to prevent rehearsel and were asked every 3 seconds to say the trigram. The results he found was that after 3 seconds 80% recalled correctly, after 18 seconds 10%. He concluded from this that the duration of the short term memry was 20 to 30 seconds.
Capicity was found by Miller (1956) that short term memorys average span was 7+ or - 2, The study for capacity was done my Baddeley et al in 1975, the aim of their study was to see if short term memory could hold more short than long words. Their participants were given either a list of long or short words then asked to recall right away in order. Results they found was that it can hold more short words
Encoding was again by Baddeley in 1966, the aim of this study was to see if short term memory was either acoustic or semantic encoding. Each group heard 5 words either; Acoustic similair/dissimilair or Semantic similair/dissimilair. The results of the study were that acoustic similair words were harder (55%) than dissimilair (75%), while semantic had little effect. From this they concluded that Short term memory relies on semantic words
Long Term Memory Studies
Again long term memory looked at duration and encoding only, as they are unable to test the capacity of the long term memory.
Duration was by Bahrick et al in 1975, the aim of the study was to test the length of the long term memory. The prodecure of it was that there was 2 groups, one group was the recognition group while the other was recall. Recognition group was shown a set of pictures and a list of names, Recall was just show the pictures both groups had to identify who the people were in the pictures. The results that they found from this was that after 47 years of being away from school, the recognition group had 60% while the recall group was only 20% of being able to indentify people in pictures. They concluded from this study that informtaion can stay in the long term memory for a life time.
Encoding was again by Baddeley in 1966, the aim was the same at the STM one just that they were shown a list of 10 words and did a task for 20 mins to prevent rehearsel. The results they found was that, semantic similair words were harder (55%) hen Dissimilair (85%) Acoustic had little effect. They concluded that long term memory encoding with semantic words.
Forgetting for STM
Trace decay is when the information can be forgotten due to passage of time
Displacement is when iteams of information can be "drop out" as there is not enough space for anything else, Old information is replaced with new.
Forgetting for LTM
Retroactive interference is when new information interferes with recalling old information
Proactive interference is when old information interferes with new information
-Context dependent forgetting is when there is retrevail clues from such learning something in the same place all the time
-State dependent forgetting is when the person is in the same physical and emotional state to recall informtion
-Retrograde amnesia is when the person cannot recal anythign prior to the injury
Anterograde amnesia is when the person cannot remember any new information
Decay is with the lack of use of the memory will lead to decay of it
Eye Witness Testimonty
Can be effecting by many things;
Role of anxiety
Age of person
Consequences of testimony
How they are tested
Eye witness testimony study part 1
This was done by Loftus and Palmer in 1974.
Aim was too see how information given to witness after event can influence their memory of event
The procedure for the experiment was that there was 45 participants (pps) which were all shown a videa then split into 5 groups, they were all asked the question of " about how fast were the cars going when they each other" when each group was given a verb to fill in the blank such as; smashed, collided, hit, bumped and contacted.
The results they got from this was that;
Smashed- 40.8mph, Collided- 39.3mph, Bumped- 38.1mph, Hit 34.0mph and Contacted 31.8mph.
Eye witness testimony part 2
Loftus and Palmer did a second study to prove there aim further,
For this one they had 150 pps they were all shown a videa agai and asked questions when they were split into 3 groups, 1 group got asked how fast they thought the cars were going when they "Hit", 2nd group got asked how fast they thought the cars were going when they "Smashed" and they 3rd groupd wasn't asked about speed. After a week from this happening they all got asked if they saw broken glass. There was no broken glass
The results they got from this was;
Group 1 (Hit) Yes-7, No-43
Group 2 (Smashed) Yes-16, No-34
Group 3 (not asked about speed) Yes-6, No-44
A strenght of this study is that it gives and insight to what people may be like in court,
A weakness is that is has limitied ecologically validity