Memory Flashcards
What is memory
The way the mind stores and resembles info
What is the duration of sensory memory
Less than half a second
What is the coding of sensory memory
Iconic- visual
Echoic- acoustic
What is the capacity of short term memory
Between 5 and 9
What is the coding in short term memory
Acoustic
What is the duration of short term memory
18-30 seconds
What is the coding for long term memory
Semantic
What is the capacity of long term memory
Unlimited
What is the duration of long term memory
Up to a life time
Procedure
Sperling 1960
Presented a grid of letters for less than a second.
Then participants were asked to recall immediately
Sperling 1960
Results
Capacity- recalled on average 4 letters
Duration- info decays in around 2 seconds
Encoding- visual
who did research on digit span and what was the research on
jacobs 1887
research on capacity of stm
how was capacity of stm investigated
participants would be asked to recall 4 digits in order out loud then 5 digits the 6 and so on until the participant cannot recall in the correct order.
was found that the mean span for digits was 9.3 and for letters was 7.3.
explain millers observations of span of memory and chunking
he observed that thing usual come in sevens. this suggests that the span of stm is 7 plus or minus 2.
he also noted that people can recall 5 words as well as 5 letters. they do this by chunking.
who did research on the duration of stm
peterson and peterson 1959
peterson and peterson procedure
24 undergraduate students. took part in eight trials. each trial the student was given a trigram to remember and a 3 digit number. they had to count backwards from that number in threes or fours until told to stop. this was to prevent rehearsal.recall was tested after 3,6,9,12 and 18 seconds. know as retention interval.
peterson and peterson findings
longer the retention interval the lower the percentage of correct responses. suggests stm has a very low duration
who did research on the duration of ltm
bahrick et al 1975
bahrick et al procedure
392 pp’s aged between 17 and 74. recall was tested in various ways such as photo recognition consisting of 50 photos , and free recall where pps recalled names of people from their graduating class.
bahrick et al findings
those tested within 15 years of graduation were 90% accurate on photo recognition. after 48 years recall declined to about 70% for photo recognition. free recall was worse than photo recognition. after 15 years it was about 60% and after 48 years it dropped to 30%. suggests ltm can last very long.
limitation of baddeleys research on coding
used artificial stimuli, the word lists had no meaning to the pp’s. means we should be cautious about generalising findings to different kinds of memory tasks. so has limited application
limitation if jacobs research on the capacity of stm.
it was conducted a long time ago ad so lacks external validity. early research often lacked adequate control. but results from other research has confirmed the findings so supports its validity.
limitation of millers research on capacity of stm
may have overestimated the capacity . cowan 2001 reviewed other research and concluded the capacity is actually only 4 the lower end of millers estimate may be more appropriate.
limitation of peterson and peterson
stimulus was artificial. trying to remember trigrams does not reflect most real life memory activities where what we are trying to remember is more meaningful. so lacked external validity.
strength of bahrick et al
used real life meaningful memories. when research with meaningless stimuli was used the results were lower. this increases the external validity.
who proposed the multi store model of memory
atkinson and shriffin 1968/71
how is information transferred from sensory register to stm
by paying attention
how is information transferred from stm to ltm
maintenance rehearsal
how is information transferred from ltm back to stm
retrieval
strength of the multi store model of memory
supported by research to show ltm and stm are qualitatively differently. baddeley found they are coded differently so supports the multi store model.
weaknesses of the multi store model of memory
suggests that ltm and stm are unitary store however research into amnesia patients suggests there are more than one type of long term and short term memory.
Craik and Watkins 1973 also suggested that maintenance rehearsal does not transfer information into ltm. Only maintains information in stm
Explain episodic memory
Refers to ability to recall events. It has been likened to a diary. For example your recent visit to the dentist and so on. Memories are time stamped. You have to make a conscious effort to recall episodic memories.
Explain semantic memory
Contains our knowledge of the world. This includes facts but in the broadest possible sense. It has been likened to a dictionary. For example it contains a number of concepts such as animals and love. Memories are not timestamped. It contains an immense collection of material which is constantly being added to.
Explain procedural memory
This is our memory for actions or skills. We can recall these memories without a conscious effort. A good example is driving a car. These are the sort of skills we might find quite hard to explain to someone else.
He came up with the types of long-term memory
Tulving 1985
Strengths of the types of long-term memory
There is clinical evidence.Case studies of HM and Clive wearing. Episodic memory in both men were severely impaired but the semantic memory was unaffected . This supports the idea that there are different memory stores. There is also evidence from brain scans. They show types of memory are stored in different parts of the brain. They found episodic and semantic memories were both recalled from an area known as the prefrontal cortex.
What are the three slave systems in the working memory model
Phonological loop
Visuo spatial sketch pad
Episodic buffer
What is the central executive
And attentional process that monitors incoming data makes decisions of allocates slave systems to tasks. Has a very limited processing capacity.
Describe the phonological loop
Deals with auditory information.
Subdivided into the phonological store and the articulatory process.
Describe the Visuo spatial sketch pad
Stores visual and or spatial information when required.
Limited capacity according to Baddeley 2003. Around 3 or 4.
Logie 1995 subdivided it into two: visual cache and inner scribe
Explain the episodic buffer
Temporary store for information integrating the visual spatial and verbal information processed by other stores
Strengths of the working memory model
Shallice and Warrington 1970 study of KF. suffered from brain damage. Poor ability for verbal information could process visual information normally. Suggest that his phonological loop had been damaged but the other areas were left in tact.
Dual task Performance supports the seperate existence of the visual spatial sketch pad.
Weaknesses of the working memory model
Baddeley Said that the central executive is the most important but the least understood component. The central executive needs to be more clearly specified. This means the working memory model hasn’t been fully explained.
What are the two types of interference
Proactive interference and retroactive interference
What is proactive interference
When an older memory interferes with a newer one
What is retro active interference
When a newer memory interferes with an older one
Mcgeogh and McDonald 1931 procedure
Pps has to learn two sets of words
Including synonyms, antonyms, words unrelated to the original ones, nonsense syllables, three digit number and no new lists
Mcgeogh and McDonald
Findings
More similarity decreased the accuracy of recall.
So interference is strongest when the memories are similar.
Strengths of the interference theory
Thousands of lab experiments have been carried out into this explanation for forgetting. Most studies show that both types of interference very likely to be ways we forget information.
Baddeley and Hitch 1977 conducted experiments with rugby players. They were asked to name the teams they had played against. this is a strength because it shows interference can be applied to everyday situations
Limitations if interference theory
Uses artificial materials. It doesn’t reflect the things we have to try and remember in everyday life. Makes interference much more likely in the lab. May not be as likely an explanation for forgetting in everyday life.
What is encoding specificity principle
States that if a cue is the help us recall information it has to be present at encoding and at retrieval. If the cues available at encoding and retrieval are different then there will be some forgetting. So e cues are meaningful whilst others are not.
Context dependant forgetting godden and baddeley 1975 procedure
Carried out an experiment with deep sea divers. They had to learn a list of words either on land or under water. They then either had to recall the words on land or under water.
Godden and baddeley findings
Accurate recall was 40% lower in the non matching conditions. The external cues there at learning were not available at retrieval so accuracy was lower.
State dependant forgetting Carter and cassaday procedure
Gave anti histamines, to the participants. Had a mild sedative effect. Either had to learn the words in normal conditions or whilst on the drug. They then had to recall the words either in noreal conditions or on the drug.
Carter and cassaday findings
When there was a mismatch between internal state at learning and recall, accuracy was significantly worse.so when the cues were absent there was forgetting.
Strengths of baddeley and godden and Carter and cassaday
There is a lot of supporting evidence to support retrieval failure. This increases the validity. It also has real life applications. For example when you go downstairs am forget what you went down for.
Limitations of baddeley and godden and Carter and cassaday
Context effects are not usually as extreme in real life situations. Environmental differences are not usually strong enough. Limitation because it means the real life applications don’t really explain much.
Loftus and palmer 1974 procedure
Showed participants clips of car crashes and then asked them questions on them. The critical question was to do with the speed of the cars. The verb of the questions was changed.eg hit smashed collided bumped
Loftus and palmer 1974 findings
The mean speed was calculated for each verb. For contacted the mean was 31.8 the mean for smashed was 40.5. Shows the question does have an influence.
Explain the response bias explanation
Suggests the wording of the question has no real effect on memory but only influences how they decide to answer.
Explain the substitution explanation
Says the wording of the question does actually change the persons memory. Those who heard the verb smashed was later more likely to report seeing broken glass even though there wasn’t any.
Gabbert et Al 2003 procedure
Showed participants the same crime but from different angles. They then discussed what they had seen before individually completing a test of recall.
Gabbert et Al findings
71% recalled aspects of the even that they had not seen but had picked up from the Co witness. In a control group with no discussion it was 0%. Shows witnessed often go along with each other to gain approval or because they think they are wrong. Known as memory conformity.
Strengths of research into misleading information
Has hugely important practical uses in the real world. Loftus 1975 believes lading questions have such a big impact that police should be careful how they word the questions when interviewing. Strength because it can help improve the legal system.
Limitations of research into misleading information.
Loftus and palmer showed video clips of accidents which is very different from witnessing an actual crime. Lacks stress. Limitation as it tells us very little about how leading questions affect witnesses in real life.
Johnson and Scott 1976 procedure
Led participants to believe they were going to take part in a lab study. While waiting in a waiting room they over heard an argument in the other room. In the low anxiety condition they saw a man walk through the waiting area hoeing a pen with grease on his hands. Other participants heard the same argument but a,so heard breaking glass. A man then walked through carrying a paper knife that was covered in blood. This was he high anxiety condition.
Johnson and Scott 1976 finding
Participants then had to pick out the man from 50 photos. 49% of those who saw the man carrying the pen were able to identify him. 33% of those who saw the man carrying the knife were able to identify him. The tunnel theory suggests this was because the witness was too busy paying all their attention on the weapon because it was the source of anxiety.
Yuille and cutshall 1986 procedure
Conducted a study on a real life shot in in a gunship in Canada. The shop owner shot the their dead. 13 witnesses took part in the study. Interviews were held 4-5 months after the incident and we’re compared to the original police interviews. Accuracy was determined by the number of details reported. They were also asked to rate how stressed they were at the time and whether they have had any emotional problems since.
yuille and cutshall 1986 findings
there was little change in accuracy after 5 months. some details were less accurate. those who reported higher levels of stress were more accurate (about 88% compared to 75% for the less stressed group).
explain yerkes dodson law 1908
states the relationship between emotional arousal and performance looks like an inverted U.
explain how daffenbacher 1983 applied the yerkes dodson law to EWT.
he said lower levels of anxiety produce much lower levels of recall accuracy. memory becomes more accurate as you increase anxiety experienced. but there comes a point where the optimum level of anxiety is reached. this is the point of maximum accuracy. anything above this accuracy declines.
limitation of johnson and scott
tests surpirse rather than anxiety. the reason the participants focus on the weapon is because they are surprised at what they see. pickel 1998 conducted a similar experiment using scissors, a handgun, a wallet and a raw chicken. it was conducted in a hairdressers. accuracy was lower with the chicken because of its unusualness. so weapon focus is due to unusualness rather than anxiety caused.
ethical issues because they are causing unnessaccary anxiety and psychological harm
limitation of yuille and cutshall
lacks control. eyewitnesses are tested sometime after the incident occured. all sorts of things would have happened to the witness during this time that the researcher has no control over. could affect the accuracy of recall.
who created the idea of cognitive interview
fisher and geiselman 1992
what are the four techniques used in the cognitive interview
report everything
reinstate the context
reverse the order
change the perspective
explain the ‘recall everything’ technique
witnesses are encouraged to include every detail of the event even if they think its not important or if they dont feel confident about it. they could be important and may trigger other important memories.
explain the ‘reinstate the context’ technique
witness should return to the crime scene in their mind and imagine the environment and their emotions. this is related to context dependant forgetting.
explain the ‘reverse the order’ technique
events should be recalled in a different chronological order to the original sequence. this prevents them reporting their expectations of how the event must have happened rather than the actual event. also prevents dishonesty.
explain the ‘ change perspective’ technique
they should recall the incident from other peoples perspectives. done to disrupt the effect of expectations and schema on recall.
explain the enhanced cognitive interview
fisher et al 1987
developed additional aspects such as reducing eyewitness anxiety, minimising distractions, getting the witness to speak slowly and asking open ended questions.
limitations of the cognitive interview
time consuming and requires special training. this means it is unlikely that the proper version of CI is actually used.
strengths of the cognitive interview
milne and bull 2002 found each element was equally valuable so using at least two of the elements could be used to improve police interviewing.
meta analysis by kohnken et al 1999 showed enhanced cognitive interview provided more correct information than the standard interview used by police. shows there are real practical benefits to the police.
