Memory

Psychology Revision Booklet

Unit 2

Remembering & Forgetting

Cognitive Psychology: Remembering and Forgetting

Models of memory including the distinguishing features/ components of each of the following: o The Multi-store model (Atkinson and Shiffrin); o Working memory model (Baddeley & Hitch)o Levels of processing(Craik & Lockheart)

Types of long-term memory: o Episodic; o Semantic; o Procedural. o Autobiographical memory.

Explanations of forgetting: o Decay, o Interference, o Retrieval failure (absence of context and cues), o Displacement, o Lack of consolidation

o Motivated forgetting, including repression.

Key Terms Memory

The mental process used to encode, store and retrieve information. Encoding

Encoding involves changing the information presented into a different form. Since words or other items in the short term store are rehearsed or repeated, we might assume that they are encoded in terms of their sound (acoustic coding). In contrast, the information we have stored in the long term memory nearly always seems to be stored in terms of its meaning (semantic coding).

Encoding takes many different forms; visual, auditory, semantic, taste and smell. Capacity

The short term store has very limited capacity, about 7 items. In contrast the capacity of the long term memory is assumed to be so large that it cannot be filled, it is said to have unlimited capacity and lasts potentially forever.

Duration

Information lasts longer in the long term store than in the short term store,. There is evidence that in the short term store, if not rehearsed, information will disappear within

about 18 – 20 seconds and in contrast there is evidence that elderly people can recognise the names of fellow students from 48 years previously.

Storage

As a result of encoding, the information is stored in the memory system; it can remain stored for a very long time maybe a entire lifetime.

Retrieval

Recovering information from the memory system. Can be known as recall or remembering.

Flashbulb memories

A flashbulb memory is a long lasting and vivid memory which we can recall in great detail. For these kinds of memories to occur the event must be surprising, unexpected, and emotionally or personally significant These memories will often be photographic in detail

Sensory memory:

Sensory memory lasts approximately ½ a second. This form of memory is ‘modality-specific’; information is stored in the same form in which it is experienced e.g. images are stored as icons.

Short-term memory:

Lasts from 18-30 seconds and memories are mainly stored as sounds (acoustically). Long-term memory:

These last from a minute to a lifetime (anything more than18 seconds!) and are stored semantically (meaning/ knowledge)

Atkinson and Shiffrin (1968) multi-store model of memory.

Two distinct stores – short-term and long-term. Stimuli from environment is held for less than one second – sensory register. Sensory Register:

o Modality-specific – information is stored in the same way in which it is registered – taste as a taste, etc.

o Capacity is large but only a brief duration – about half a second.

o Processing is mostly unconscious and has to be deduced from experiments.

o Sperling (1960) indicated it holds at least 9 items but only for a brief period of time.

Short-term Memory:o Sensory register can be lost or is passed on to STM.o (1956) Miller published “Magical Number Seven” –

showed limit of STM to be between five and nine, on average 7.

o Can be extended through “chunking”.o If information in STM is rehearsed it can be retained in

STM storage and transferred to LTM for potentially indefinite storage.

Long-term Memory:o Refers to anything that we can remember for a period of time lasting from minutes to a life-time.o Has a huge capacity and seems to be able to store memories in a number of forms.o Mostly abstract/semantic and there is evidence it is stored in an organised and meaningful way.

Research evidence

The case of Clive Wearing (1985)

On March 27, 1985, Wearing, then an acknowledged expert in early music at the height of his career with BBC Radio 3, contracted a virus which normally causes only cold sores, but in Wearing's case attacked the brain (Herpes simplex encephalitis). Since this point, he has been unable to store new memories. He has also been unable to control emotions and associate memories well.

Wearing developed a profound case of total amnesia as a result of his illness. Because the hippocampus, an area required to transfer memories from short-term to long-term memory is damaged, he is completely unable to form lasting new memories – his memory only lasts between 7 and 30 seconds. He spends every day 'waking up' every 20 seconds, 'restarting' his consciousness once the time span of his short term memory elapses (about 30 seconds). He remembers little of his life before 1985; he knows, for example, that he has children from an earlier marriage, but cannot remember their names. His love for his second wife Deborah, whom he married the year prior to his illness, is undiminished. He greets her joyously every time they meet, believing he has not seen her in years, even though she may have just left the room to fetch a glass of water. When he goes out dining with his wife, he can remember the name of the food (e.g. chicken); however he cannot link it with taste, as he has forgotten.

Despite having retrograde as well as anterograde amnesia, and thus only a moment-to-moment consciousness, Wearing still recalls how to play the piano and conduct a choir – all this despite having no recollection of having received a musical education.

In a diary provided by his caretakers, Clive was encouraged to record his thoughts. Page after page is filled with entries similar to the following:8:31 AM: Now I am really, completely awake.9:06 AM: Now I am perfectly, overwhelmingly awake.9:34 AM: Now I am superlatively, actually awake.

Earlier entries are usually crossed out, since he forgets having made an entry within minutes and dismisses the writings–he does not know how the entries were made or by whom, although he does recognize his own writing. Wishing to record the important life event of "waking up for the first time", he still wrote diary entries in 2007, more than two decades after he started them. Wearing can learn new practices and even a very few facts–not from

episodic memory or encoding, but by acquiring new procedural memories through repetition. For example, having watched a certain video recording multiple times on successive days, he never had any memory of ever seeing the video or knowing the contents, but he was able to anticipate certain parts of the content without remembering how he learned them.

Watch a video about clive: http://www.youtube.com/watch?v=wDNDRDJy-vo

Miller’s magical number 7 (1956)

He found in a series of memory experiments that people could on average recall 7 items (+/- 2). This is evidence for the existence of limited capacity in STM because it shows that we can only hold a small amount of information in STM at any one time.

Baddeley (1966)

Aim: To investigate encoding in STM and LTM Method: Ps had to recall a list of words either immediately (STM) or 20 mins later (LTM). The groups either learned acoustically similar words (rain, pain, train) or semantically similar words (quick, fast, swift). Results: Immediate recall- most mistakes with acoustically similar words. 20 min recall- most mistakes with semantically similar words.

Conclusion: Acoustic code was used in STM, evident by the acoustic confusion. Information is stored semantically in LTM, again because of the semantic confusion

Evaluation of research :

The research evidence supporting this model are either lab experiments or case studies:

- Problem with case studies is that they are limited in their generalisability due to the individual differences between people e.g. others may use their hippocampus and memory in a different way to Clive wearing and therefore this case would not apply to the way the general population use their memory in everyday life. The traumatic disease may also have caused Clive’s brain to rewire itself in a different way (plasticity of the mind) again meaning it would not generalise to the memory systems of the population as he may be using his memory system in a different way.

- Laboratory experiments testing memory involve artificial memory tasks which do not reflect the way we learn and recall information in everyday life, this means the results from such studies may not generalise as we may use our memories in a different way in everyday life.

Evaluation of the multi-store model :

o Very simplistic model, neuroimaging shows our memory system is very complex and many systems overlap. Over-simplistic view that STM and LTM structures operate in a single, uniform fashion. Working model is a more active model of human processing.

o The idea that STM are transferred to LTM via rehearsal cannot explain how we can have LTM for things which we have not mentally rehearsed. Model of STM doesn’t take into account the fact that in daily life people devote little time to active rehearsal, although they are constantly storing new information into the long-term memory. Rehearsal may describe what happens in laboratories but is not true to real life.

o Case of CW shows different types of memories are stored in different places, he has LTM and STM for up to 18 seconds. It also supports the idea of LTM being encoded through rehearsal as Clive seems to have lost the ability and cannot for new LTM.

o Case of KF shows different types of memories are stored in different , he had a motorcycle accident that left him with a

severely impaired STM but he could still make new LTM, suggests they are stored in separate places.

o This model cannot explain why some things are easier to remember than others e.g. emotionally significant events & flashbulb memories.

Working Memory Model Baddeley & Hitch (1974)

Alan Baddeley and Graham Hitch proposed a model of working memory in 1974, in an attempt to describe a more accurate model of short-term memory.

Central Executive

The central executive is a flexible system responsible for the control and regulation of cognitive processes. It has the following functions:

binding information from a number of sources into coherent episodes

coordination of the slave systems shifting between tasks or retrieval strategies selective attention and inhibition

It can be thought of as a supervisory system that controls cognitive processes and intervenes when they go astray.

Phonological Loop

The phonological loop consists of two parts, the articulatory control system and the phonological store:

Articulatory Control System (The Inner Voice) The articulatory control system rehearses information verbally and has a time based capacity of about 2 seconds. It is helpful to think of it as the system that you use to mentally rehearse information by repeating it over and over again.

Phonological Store (The Inner Ear – but not to be confused with the canals in your actual ear) The phonological store uses a sound based code to store information, but this information decays after about 2 seconds, unless it is rehearsed by the articulatory control system. The phonological store receives its input either directly from the ears or from long term memory. If you imagine your favourite piece of music you are using your phonological store.

Visuospatial sketchpad

The visuospatial sketchpad is assumed to hold information about what we see. It is used in the temporary storage and manipulation of spatial and visual information, such as remembering shapes and colours, or the location or speed of objects in space. It is also involved in tasks which involve planning of spatial movements, like planning one's way through a complex building

Episodic buffer

In 2000 Baddeley added a fourth component to the model, called 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 semantic meaning

Research evidence:

The case of KF (1972)

Patient KF was brain damaged in a motorbike accident and had problems with his short term memory.

He had problems with spoken numbers, letters and words and with significant sounds (such as doorbells and cats meowing).

The parts of short term memory dealing with visual memory were unaffected. This shows that visual and sound information are stored in separate stores in the STM

as only one of these was affected by KFs brain damage.

Simon & Chabris (1999)

Perception experiment asked participants to count the number of basketball passes by the white team (versus black)in a short film. They found participants did not notice the gorilla when counting the basket ball passes. This shows our visuospatial sketchpad has a limited capacity as we can only attend to one visual stimulus at a time.

Baddeley et al (1975)- word length effect.

Presented words for very brief periods of time. One condition – 5 words, one syllable, familiar. Two condition: 5 polysyllabic words. Average correct recall over several trials showed participants remembered the short words much better. This is the ‘word length effect’. This shows that the phonological loop has a limited capacity

Evaluation of research:

All the research evidence supporting this model is either lab experiments or case studies:

- Problem with case studies is that they are limited in their generalisability due to the individual differences between people e.g. the traumatic accident KF experienced may have caused his brain to rewire itself in a different

way (plasticity of the mind) again meaning it would not generalise to the memory systems of the population as he may be using his memory system in a different way.

- Laboratory experiments testing memory involve artificial memory tasks which do not reflect the way we learn and recall information in everyday life, this means the results from such studies may not generalise as we may use our memories in a different way in everyday life.

Evaluation of the working memory model:

Weaknesses

WMM only concerns itself with STM and is not a comprehensive model of memory, it does not explain how LTM are formed of stored.

What is the function of the Central Executive? Least is know about the most important component of Working Memory. It isn’t clear how it works or what it does. This vagueness means that it can be used to explain almost any experimental results and it has never been measured.

Practice time? WMM doesn’t explain changes in processing ability that occur as a result of practice or time.

Strengths

Extremely influential model and most psychologists use it in preference to the STM as it shows the complexity of STM.

Research support comes from dual-task studies, although such studies are rather artificial. However patients like KF could remember visual but not verbal stimuli in STM so must be at least two systems in STM.

Physiological evidence exists using studies involving brain scans. PET scans have shown that different areas of the brain are used while undertaking verbal and visual tasks. These areas may correspond to components of WMM.

It attempts to explain how memory actually functions. Evidence has been presented that suggests the phonological loop plays a key role in the development of reading and the phonological loop is not operative in some children with dyslexia. This loop helps us comprehend complex text and learn new spoken vocabulary.

This model is still being developed and applied today e.g. people with sensory deprivation (deaf/ blind), do they

have/use their visuospatial sketchpad/phonological loop without

these sensory experiences? Research suggests they may use these systems in a different way e.g. cases of blind people using their visual system to create visuospatial images through sound (echolocation) e.g. Ben Underwood. Professor Dutton in Glasgow is using the technique with blind children.

Watch a video about Ben http://www.youtube.com/watch?v=G1QaCeosUmw&feature=related

Levels of processing Craik and Lockheart (1975)

Is very different to the MSM and WMM as it:

– Emphasis on process rather than structure

– Strength of a memory trace is determined by how the information is processed

Strength of trace depends on:

– Attention paid to stimulus

– Depth of processing carried out

– Connections with existing knowledge

• Craik & Lockhart distinguished between 2 types of rehearsal:

1. Maintenance rehearsal , e.g. repeating words led to a shallow memory which was easily disrupted

2. Elaborate rehearsal, analysing the meaning of the material = deeper processing and results in a stronger, longer lasting memory

This model proposes that it is the way that information is processed which determines its strength and duration not the store it is in. This model outlines that there are three levels of processing; shallow (e.g. visual processing of how something looks), intermediate (e.g. phonetically processing how something sounds) and deep processing (e.g. semantically processing the meaning of something). This theory states that shallow and intermediate processing will result in a weak memory whereas deep semantic processing will result in the longest duration and strongest memory.

Research evidence:Craik and Tulving (1975)

• Aim: To investigate how deep and shallow processing affects memory recall.

• Method: Participants were presented with a series of 60 words about which they had to answer one of three questions. Some questions required the participants to process the word in a deep way (e.g. semantic) and others in a shallow way (e.g. structural and phonemic). For example: Structural / visual processing: ‘Is the word in capital letters or small letters?Phonemic / auditory processing: ‘Does the word rhyme with . . .?’Semantic processing: ‘Does the word go in this sentence . . . . ?

• Participants were then given a long list of 180 words into which the original words had been mixed. They were asked to pick out the original words.

• Results: Participants recalled more words that were semantically processed compared to phonemically and visually processed words.

• Conclusion: Semantically processed words involve elaboration rehearsal and deep processing which results in more accurate recall. Phonemic and visually processed words involve shallow processing and less accurate recall.

Evaluation of research:+ This study has been replicated many times with similar results making it reliable and as a lab study it is controlled meaning we can use the results of this research to apply to the real world as this effect is clearly not the result of anomalies in the environment e.g. this could help people who have lost memories following as accident by using semantic learning techniques to encourage deep processing and therefore strong new memories.

Evaluation of the levels of processing model:

+ This explanation of memory is useful in everyday life because it highlights the way in which elaboration, which requires deeper processing of information, can aid memory. An example where it could be used is revising for an AS exam, using semantic processing (e.g. explaining memory models to your mum.) and should result in deeper processing through using elaboration rehearsal. Consequently more information will be remembered (and recalled) and better exam results should be achieved.

+ The theory is an improvement on Atkinson & Shiffrin’s account of transfer from STM to LTM. It showed that encoding was not a simple, straightforward process. Hundreds of experiments showed 'deep' semantic processing leads to stronger memories. It explains why we remember some things much better and for much longer than others.

- It does not explain how the deeper processing results in better memories. The concept of depth is vague and cannot be objectively measured. Deeper processing takes more effort, it could be this, rather than the depth, which affects the strength of a memory.

- The levels of processing theory focuses on the processes involved in memory, and thus ignores the structures. There is evidence to support the idea of memory structures such as STM and LTM e.g. Clive Wearing/ Peterson & Peterson/ Miller/ HM.

Discuss the levels of processing model of memory. 10m

The levels of processing model differs from the Multistore Model and Working Memory Model as it emphasises the processes which lead to the formation of a memory rather than the structure of memory. According to this model it is the depth of processing that determines the strength of the memory, not which store it is in. This model outlines that there are three levels of processing; shallow (e.g. visual processing of how something looks), intermediate (e.g. phonetically processing how something sounds) and deep processing (e.g. semantically processing the meaning of something). This theory states that shallow and intermediate processing will result in a weak memory whereas deep semantic processing will result in the longest duration and strongest memory.

Research to support this model largely comes form laboratory experiments such as the one devised by Craik and Tulving (1975). In the experiment participants were presented with a series of 60 words about which they had to answer one of three questions. Some questions required the participants to process the word in a deep way (e.g. semantic) and others in a shallow way (e.g. structural and phonemic). The then had to select the words they had already viewed form a lost of 180 words. They found that people recalled many more of the words they had processed semantically demonstrating that it is the depth of processing that determines the duration of a memory and that semantic processing is indeed the deepest. This study has been replicated many times with similar results making it reliable and as a lab study it is controlled meaning we can use the results of this research to apply to the real world as this effect is clearly not the result of anomalies in the environment e.g. this could help people who have lost memories following as accident by using

semantic learning techniques to encourage deep processing and therefore strong new memories.

However, there has also been some issue with the concept of ‘deep processing; in this model which has never been formally defined and as it is not clearly exactly how this deep processing alters the structure of the brain it is impossible to accurately and objectively measure whether or not deep processing has taken place. In addition to this deeper processing often takes more effort and it could be this, rather than the depth, which affects the strength of a memory. Despite these criticisms the model has been applied in the real world to enhance learning through an understanding of how we can remember some information more easily that others by processing it semantically, this has been used to help students learn more effectively e.g. revising with a friend and explaining the subject to one another promoting deeper understanding and deeper processing of the information. However, the levels of processing model fails to acknowledge or explain the structural aspects of memory e.g. it cannot explain cases like Clive Wearing who experience difficulties with particular types of memory (forming any new LTM) which cannot be accounted for by this model. Due to all these limitations it might be best to form a new model of memory combining our knowledge of both structure and processing from the multistore, working and levels of processing models of memory to create a complete theory of memory.

Types of long-term memory:

o Semantic: the memory of meanings and facts based on knowledge not experiences e.g. in which country is the Eiffel tower? What colour is the sea?

o Procedural: skills and procedures, or "how to" knowledge which we can ‘proceed’ to do or act out e.g. riding a bike or swimming.

o Episodic: the memory of events (times, places, associated emotions, and other contextual knowledge) that can be explicitly stated e.g. what you ate yesterday and the last person you sent an email to.

o Autobiographical memory: the memory of specific life events that have personal meaning e.g. your first love, the best holiday you ever went on, the day you got married.

Research evidence to show that there are different types of LTM which are likely to be stored in different areas of the brain:

Demonstrated in the case of Clive Wearing who retained many procedural memories (e.g. he could still play the piano) and semantic memories (e.g. he knew he was a musician and was married) but lost his

episodic and autobiographical memories (e.g. he could not remember his wedding day or famous music concerts he directed). Shows only some of his LTM were affected by the virus that damaged his memory and therefore they must be stored in different places.

Demonstrated in the case of HM who following the removal of his hippocampus could not form new episodic memories (did not remember things that happened to him) but was able to learn new skills or procedural memories. He could not remember doing the tasks before but over time he got better at them e.g. the star mirror drawing task. Shows only some of his LTM were affected by the operation and therefore they must be stored in different places.

Video about HM: http://www.youtube.com/watch?v=IKP6tBhM2T4

Forgetting: you need to know which are

explanations of forgetting in STM and which are in LTM!

TRACE DECAY (STM) DISPLACEMENT (STM) RETRIEVAL FAILURE (LTM)

Information that enters STM leaves a trace in the brain, neural activity dies away unless material is rehearsed. Hebb = whilst new learning is taking place the engram is delicate; with learning a permanent engram is formed.ENGRAM: a change in neural tissue (in the brain) that represents what has been learned.

Limited number of slots for information to fit into (Miller found approx 7 + or – 2).When the system is too full the oldest material is ‘pushed out’ or displaced & lost (forgotten!).

Memories cannot be recalled because retrieval cues are not present e.g. tip of the tongue phenomenon.Context dependent forgetting: occurs if environmental variables present during learning are missing at recall (external cue)State dependent forgetting: absence of physical/ psychological variables present during learning (internal cue)

Evaluate theory:Consistent with the MSM as this theory suggests STM has a limited duration.It is difficult to test because you cannot prevent rehearsal which would strengthen the memory.

Evaluate theory:Is consistent with the MSM of memory, however, later theories such as the working memory model provides evidence that STM may be multiple stores rather than one which would

Evaluate theory:Can explain how you can forget something at one time and recall it later = the correct cues are present later on in the environment.Most research in on extreme/ unusual cases e.g. deep sea divers

Trace decay cannot explain how you can forget things at one time but remember them later.

mean forgetting could not be things being ‘pushed out’ of a single store. Displacement cannot explain how you can forget things at one time but remember them later.

& alcoholics = may not generalise to everyday forgetting.Can be applied to life e.g. students perform better on exams when they take them in the same classroom in which they learned the material = environmental cues trigger memory.

Peterson & Peterson (1959)Aim: To test the decay theory of forgetting in STM.Procedure: Participants had to recall trigrams (three letters, eg. TGH). To prevent rehearsal participants were asked to count backwards in threes from a specified number. Participants were asked to recall the trigram after intervals of either 3, 6, 9, 12, 15 or 18 seconds. Findings: The longer the interval delay the less trigrams were recalled. 80% of trigrams after a 3 seconds delay, after 18 seconds roughly 5% of trigrams were recalled. Conclusion: Short-term memory has a limited duration when rehearsal is prevented. It is thought that this information is lost from short-term memory due to trace decay.

Waugh & Norman (1965)Serial probe technique: List of numbers presented and asked to tell the number after the probe (number before) in the list. The time in seconds at which numbers were presented (1-4seconds) had no effect on recall. Numbers were remembered better if they were at the end of the sequence Conclusions: Supports displacement as later trigra ms pushed out earlier ones.

Godden & Baddeley (1975)Aim: Do environmental cues effect recall?Procedure: Deep sea divers learned words on land and underwater, words were recalled in the same and a different environment.Findings: They remembered 30% less when they were in a different environment to which they learned the material.Conclusions: Forgetting can be caused by retrieval failure due to a lack of cues in the environment.

Evaluate research:Artificial task which makes demand characteristics more likely and means participants may not be using their memory systems in the same way as in everyday life, this means that the research may not be generalisable to forgetting in everyday life as we may forget for different reasons than the ones exposed in this experiment e.g. …………….

Evaluate research:Artificial task which makes demand characteristics more likely and means participants may not be using their memory systems in the same way as in everyday life, this means that the research may not be generalisable to forgetting in everyday life as we may forget for different reasons than the ones exposed in this experiment e.g. …………….

Evaluate research:This experiment is ecologically valid as it was conducted in real life settings meaning that behaviour is likely to be more natural and free from demand characteristics, meaning we could generalise from this study to other similar real life settings such as when students learn in a classroom and yet forget the information in the exam, here they would be lacking the environmental cues from the classroom to trigger memories for things learned in the lesson.

INTERFERENCE (LTM) LACK OF CONSOLIDATION (LTM)

MOTIVATED FORGETTING (LTM)

Information is prevented from passing from STM-LTM.As the amount of information in LTM increases interference can also occur from competing memories already stored interfering with new ones.Proactive interference: earlier learning interferes with what you are learning in the present.Retroactive interference: recent learning interferes with the recall of earlier learning.

STM - - become - -> LTM due to consolidation (e.g. rehearsal) by repeatedly activating a memory. If something interrupts the process then the STM cannot consolidate and the memory is not stored (e.g. a bang on the head!).

Painful memories = overwhelming anxiety. These memories are repressed and stored in the unconscious so they cannot influence conscious emotions. Can be accessed using Freudian techniques such as dream analysis. Memories can be retrieved into conscious memories once the emotional tension is released e.g. through psychoanalytic therapy. Recovered memories of trauma can then be overcome.

Evaluate theory:Most studies have tested episodic memory – semantic memory (knowledge) may be more resistant to interference. Can be applied to real life e.g. You change phone and you cannot remember your old number = retroactive interference.You are trying to learn a new language (Spanish) but you keep getting mixed up and saying French words = proactive interference.

Evaluate theory:Studies have shown periods of sleep following learning tasks improve recall = chance to consolidate information. Can be applied to life: Concussed patients often forget what happened to them prior to the concussion = prevented them rehearsing information so was lost e.g. princess Diana’s bodyguard was the sole survivor but does not remember the circumstances of the crash.ECT causes loss of memory just prior to treatment = prevented them rehearsing. Research shows if you delay the treatment for 1 hour after learning = perfect memory.

Evaluate theory:Evidence for repression is based more on belief (faith) than proof as it is impossible to scientifically test the contents of the unconscious mind.So called ‘recovered memories’ are often later shown to be false e.g. Loftus studies implanting false memories. Shows often memories may be placed in the persons mind by the therapist = suggestive therapy. Legal ramifications for people can be damaging – people have gone to prison.Other research (e.g. on flashbulb memories) shows highly emotional memories are often much stronger then others = less likely to forget & cannot be explained by motivated forgetting.

Keppel & Underwood (1962)Aim: To investigate proactive interference and recall.Procedure: Ps learn trigrams (e.g. HTY) and count backwards to either 3, 9 or 18 seconds. Findings: Almost 100% recall on first trial whether 3, 9 or 18 seconds but recall decreased as number of trigrams presented increased.Conclusions: The more trigrams they saw the less they remembered = subsequent trigrams seen ‘interfere’ with earlier ones.

Yarnell & Lynch (1970)Aim: To investigate lack of consolidation and memory loss due to concussion. Procedure: A field study was conducted with footballers who experienced concussion – they asked for details of events immediately after the accident and 20 minutes later.Findings: Ps could recall events immediately after but not after 20 minutes. Conclusions: Memories had not had a chance to consolidate the events and therefore they did not form LTMs.

Glucksberg & Lloyd (1967)Aim: Investigate motivated forgetting. Procedure: Participants learned a list of paired words A – B (e.g. tree – apple); they then learned a second list that were associated with Bs on the first list (e.g. apple – red). On the second list during the learning of each word pair participants were given an electric shock. They were then asked to recall the words.Findings: The words that were associated with the shock were remembered less than the non-shock words.Conclusions: Words with unpleasant associations (shocks) were repressed and therefore could not be consciously recalled.

Evaluate research:Artificial task which makes demand characteristics more likely and means participants may not be using their memory systems in the same way as in everyday life, this means that the research may not be generalisable to forgetting in everyday life as we may forget for different reasons than the ones exposed in this experiment e.g. …………….

Evaluate research:This experiment is ecologically valid as it was conducted in real life settings meaning that behaviour is likely to be more natural and free from demand characteristics, meaning we could generalise from this study to other similar real life settings such as when patients experience memory loss for events shortly before they suffer a head trauma in a car accident.

Evaluate research:A key problem with this study is the measure itself as the research is aiming to support a theory proposing we forget due to emotional trauma but is testing it by creating physical pain, you could argues that a comparison between physical and emotional pain is invalid because these are two very different experiences.