Memory - AS

1) Encoding - changing sensory info into a meaningful form to be processed in memory

2) Capacity - how much info can be stored

3) Duration - how long info can be stored

Short term memory:

• Encoding = acoustically (sound)
• Capacity = 7±2 items of info
• Duration = 20-30 seconds

Long term memory:

• Encoding = semantically (meaning)
• Capacity = unimited
• Duration = unlimited

Researcher: Baddeley (1966)

Participants were given 4 sets of words to recall in order. For the STM task this was done immidiately.

A) Set 1 = words that sounded similar (eg. cat, mat , map)

B) Set 2 = words that sounded dissimilar (eg. deg, bin, cup, pen)

• pps made more erros with similar sounding words
• eg. cap and cap, S and X, P and B, M and N

+ Large sample size of 72 = reduced chance of anomalies = results can be generalised

+ Followed a standard procedure = experiment is reducible with same words/equipment

- low eco validity = word lists are not recalled in everyday life

- does not consider different types of encoding

Researcher: Miller (1956)

A) participants given 3 random letters to recall, which took up 3/7 of STM capacity eg. CEGS

B) participants given 3 meaningful letters to recall, which took up 1/7 STM capacity eg. GCSE

• pps could recall 7±2 random letters on average

- does not address/account for influence of the material on an individual eg. PFA means something to a football fan whereas it doesn't mean anything to another individual

- size/content of chunks may vary

Researcher: Peterson x2 (1959)

1) pps to remember a trigram eg. HGW

2) pps recall trigrams after intervals eg. 3sec, 6sec, 9sec

3) during intervals, pps counted backwards in 3s

• 90% recall achieved after 3sec
• 6% recall achieved after 18sec

= proves recall of trigrams decreases steadily as the retention interval lengthens

= if rehearsal  is prevented then info vanishes from STM, therefore, decay is yje mechanism of forgetting in STM

+ lab study = use of standard procedure = reproducible

- possible that loss of info is down to capacity limitations rather than duration

- interference for ealier trigrams may cause poor recall, not simply decay

- trigrams are artificial = do not reflect everyday memory

Researcher = Baddeley (1966)

Participants were given 4 sets of words to recall in order. For the LTM task this was done after a 20min interval.

A) Set 1 words were semantically similar (great, big, large)

B) Set 2 words were semantically dissimilar (hot, old, late)

• recall for semantically similar = 55%
• recall for semantically dissimilar = 85%

+ 75 pps used = more representative of target pop = high generaliseability

- evidence from other studies show that acoustic and semantic are not the only forms of encoding therefore, this research can be said to be inconclusive

- only LTM for words was tested, not memories or skills

Researcher = Bahrick (1975)

1) 400 pps were asked to remember the names of former classmates

2) pps were also shown photo lists of names to identify (recognition task)

• left school 15 years ago = recalled 90% of classmates
• left school 48 years ago = recalled 80% names and 70% of faces
• free recall of names was poor
• ecognition easier than free recall, suggests that we process lots of info through our LTM but we need cues to access it

+ high level of mundane realism ---> remembering faces is a task relating to real-life settings

+ experimental support ---> findings are supported by Shepard

- lacked important controls such as pps may have been in contact with friends or looked in the yearbook

- lacks internal validity as it only tested one form of LTM (visual)

Created by Tulving (1972)

LTM is divided into 2 main types: explicit (declarative) and implicit (procedural) memory

Episodic and semantic memories are examples of knowing that ---> explicit/declarative memories

Procedural memories involve knowing how to do things - does not involve conscious thought

Episodic memory:

• refers to any events that can be reported from a person's life
• it is a type of 'declarative' memory (explicitly inspected + recalled consciously)
• has 3 elements: specific details of the event, context and emotion
• eg. our memory of the first day of school, we may remember the place of the event and who was there, what happened before or after event (context) and how we felt during this time (emotion)

Semantic memory:

• also a type of declarative memory (explicitly inspected + recalled consciously)
• involves the recall of facts with meaning
• usally begin as episodic memories because knowledge is acquired from personal experiences
• then a gradual transition fromepisodic to semantic as memory slowly loses its association to particular events
• eg. recalling that you listen to music using your ears does not require knowing when or where you acquired this fact

Procedural memory:

• concerned with skills and remembering how to do something
• typically acquired through repetition and practice
• type of implicit memory(unconscious because they have become automatic)
• eg. riding a bike requires repetition and practice but once learned, we can unconsciously perform it with relative ease

Evidence from brain scans:

• diff areas of brain active when diff kinds of LTM are active
• eg. Episodic memory ------> hippocampus, temporal lobe and frontal lobe
• eg. Semantic memory -----> temporal lobe
• eg. Procedural memory ----> cerebellum

Evidence from amnesiacs:

• HM case study ----> ability to form new LTMs was affected by destruction of hippocampus but pre-existing LTMs remained
• Destruction of hippocampus = difficulty retaining episodic + semantic info
• However, procedural memory appears to be largely unaffected ( can recall pre-learned skillls and acquire new skills)

Researcher = Atkinson + Shiffrin (1968)

Describes memory in terms of info flowing through a linear system

• info detected by sensory organs then enters SM
• if attended to, this info is transferred to STM
• without attentionthis infor simply decays
• with rehearsal, info can be transferred to LTM

+ evidence for distinction of seperate stores (STM+LTM)

+ accounts for primacy and recency effect

+ supports studies of amnesiacs (H.M 1953)

- model is over-simplified ----> attention isnt always needed

- STM+LTM are not unitary stores but instead are comprised of diff stores

- does not consider diff typres of LTM (eg. episodic, semantic, procedural)

- model over-emphasises significance of rehearsal (ppl dont usually actively rehearse info to commit it to memory, traumatic events often don't need rehearsal to enter tthe LTM)

- has been critisized for being a passive/linear model

Researcher: Baddeley + Hitch (1974)

Considers the STM to be comprised of 3 limited capacity stores

Central executive ---> manages attention, allocates data to the subsystems also used in problem solving

Phonological loop ---> temporarily retains language-based info

• Articulatory-phonological loop (inner voice) ----> linked to speech production and is used to rehearse and store verbal info
• Phonological store (inner ear) ----> holds auditory speech and the order it was heard

Visual-spatial sketchpad ---> processes and retains info about objects and their position in relation to other objects

+ provides explanation for parallel processing unlike MSM

+ Shallice + Warrington (1974) case study reported that brain-damaged patient KF could recall verbal but not visual info immidiately after its presentation ---> supports WMM's claim that there are seperate and unitary STM stores

+ model was developed using evidence from lab experiments so confounding variables could be carefully controlled to produce reliable results

- critisized for being too simplistic and vague ----> unclear what CE is or its role in attention

- results from ad experiments often have low eco validity

Interference = the storing of similar memories that impedes retrieval

• a case of accessibility
• occurs when 2 pieces of info become confused with one another, resulting in one or both items being forgotten

Proactive interference

• previous learning interferes with subsequent learning
• eg. old telephone no. proactively interferes/ hinders our abiity to recall our new telephone no.

Retroactive interference

• the tendancy of later learning to hinder the memory of previously learned material
• eg. inability to remember new post code as we have become accustomed to our new post code

+ there is research evidence to back this up: Baddeley + Hitch (1977)

1) rugby players asked to recall names of teams played that season

2) % of forgetting increased with more games played ---> inuitively correct as it occurs in everyday life (mundane realism)

- limited scope as this theory can only explain a lack of recall when info in a similar format prevents recall

- poor eco valid ---> predominantly lab based so control over variables but it is unnatural environment meaning nunnatural behaviour likely occurred

= described as the incapacity/failure to recall a memory due to missing stimuli or cues that were present at the time the memory was encoded

Researcher = Godden and Baddeley (1975)

1) sea divers were given lists of words to recall on land or underwater

• recall was better when it was conductedin the same environment the material was learned
• suggests that environmental cues affect the accuracy of memories

+ field experiment = higher eco valid as the behaviour observed is likely to be more authentic

+ practical applications eg. helps falicitate recall from eye witnesses

- conditions too extreme = eg. small differences such as a classroom + exam hall being used, the environment would have less impact on recall

- sample = divers only ---> so representative only for other divers ---> lacks generaliseability

- not everything was controlled fully such as the weather and the fitness of divers

- high number of words were still not recalled when in the same environment ---> suggests that there are other explanations for forgetting other than environmental cues

Poor reconstruction of memories is why EWT can be inaccurate

EWT can be affected by:

• schemas
• post event discussion
• anxiety
• leading questions

Researcher = Johnson + Scott (1976)

Condition A:

• pps sat on their own in a waiting room
• pps overheard a heated argument between 2 people
• seconds later, one of them ran through the room holding a letter opener covered in blood ------> high anxiety

Condition B:

• pps sat on their own in a waiting room
• pps overheard a quiet conversation
• seconds later, one of them walked through the room holding a pen
• ------> low anxiety

low anciety = 49% accurate identification of person

high anxiety = 33% accurate identification of the person

Few people noticed the pen whereas most pps noticed the letter opener ---> focus on the weapon may prevent people noticing important aspects of a crime

- ethivcal guidelines broken as pps were decieved about the "knife crime" and so could have caused stress

- pps anticipated something happening and so experiemnet does not fully reflect effect of conditionon anxiety

- study may test suprise rather than anxiety: Pickrell (1998)

Researcher = Loftus + Palmer (1974)

1) pps saw video of traffic collisions then given questionnaire to test immediate recall of events

2) control group = how fast was the car when it "HIT" the other

3) other 4 groups hit was replaced with "CONTACTED, COLLIDED, BUMPED or SMASHED"

• "SMASHED" condition ----> highest speed estimates

• "CONTACTED" condition ----> lowest speed estimates

4) pps were also asked if they noticed any broken glass

• 47% of pps in "SMASHED" condition ----> said yes
• 16% of pps in control condition -----> said yes

= types of questions asked related to event can distort memory or influence the answer

+ the use of questionnaires means the study has high validity due to standardised procedures (questions) with no input by the researcher, it can be replicated to test consistency

+ lab experiement = high internal validity due to the strict control over EVs however....

- lab experiment ---> artificial stimulus as videos of car crashes used = doesn't reflect real life where pps would be without warning and therefore, lacks external validity

- use of college students = lacks pop validity outside of that uni ---> cannot be generalised to whole world

Conformity effect

Researcher = Gabbert et al (2003)

1) pps were put into pairs and watch a different video of the same event

2) pps in condition A then discussed events with pps from condition B

3) 71% of pps mistakenly recalled aspects of the event that they did not see

4) control group = no discussion ---> no errors made

Repeat interviewing

= each time an eye witness is interview there is a possibility that comments from the interviewer can be incorporated into own recollection of events ---> children

Researcher = Gieselman et al (1985)

1) pps viewed a film of a violent crime

2) after 48 hours pps were interviewed with cog interview, standard interview and hypnosis

• av no. of correctly recalled facts with cog interview = 41.2
• av no. of correctly recalled facts with standard interview = 38.0
• av no. of correctly recalled facts with hypnosis = 29.4

= suggests that cog interview leads to better and more accurate memory for events, with witnesses able to recall more relevant info compared to a traditional interview method

- lacks eco valid ---> pps watched filmed incidents not real life experiences

Mental reinstatement of original context:

• encourages the witness to mentally recreate both the physical and psychological environment of the original incident
• perhaps asking them about general activities and feelings on the day eg. sights, sounds, emotions, the weather etc.

Report everything:

• encourages the witness to report every detail without editing anything out, even if they think that detail is trivial
• In this way, some unimportant detail might act as a trigger for key info about the event - CUES

Change order:

• recounting the incident in a different narrative order
• Geiselman proposed that due to the recency effect, people tend to recall more recent events more clearly than others
• Witnesses should be encouraged to work backwards
• Also, changing order can reduce the influence of schemas on memory as they can alter our recollection of post events (Bartlett)

Changing percepective:

• witnesses are asked to report the incident from different percepectives eg. another present witnesses prospective
• Also disrupts the effect of schemas on recall

+ Fisher et al (1990) found that witnesses reported greater detail in their accounts of crimes when detectivesused technique

+ technique is more structured than standard interview

- Koehnken et al (1999) found witnesses recalled more incorrectt info with cog interview compared to standard interview perhaps because more detail ---> more % of mistakes made

- more time-consuming than standard interview