Memory

• Outline Research on Coding

  • The process of converting information from one form to another is called coding.
  • Baddeley gave different lists of words to participants to remember.
  • Similarly sounding words, different sounding words, words with similar meanings and words with different meanings.
  • Participants were shown the original words and asked to recall them in the correct order.
  • When doing this immediately (STM) they tended to do worse with acoustically similar words.
  • If they recalled after 20mins (LTM) they did worse with the semantically similar words.
  • This suggests that information is coded semantically.
  • Mille observed everyday practice, noting that most things come in 7s, suggesting capacity is 7+-2 items.
  • He also noted that people can recall 5 letters and 5 words by chunking.
• Outline Research on Capacity

  • Jacobs developed a technique to measure digit span.
  • The researcher gives 4 digits and the participant is then asked to recall these in the correct order out loud.
  • If correct, the researcher reads out 5 digits and so on until the participant can't recall the order correctly.
  • This determines the individual's digit span.
  • Across participants, this was 9.3 for numbers and 7.3 for letters.
• Outline research of duration (STM.)

  • Peterson tested 24 undergrads that took part in 8 trials.
  • Each student was given a trigram to remember and a 3 digit number to count back from to prevent mental rehearsal.
  • On each trail they were told to stop after a different amount of time in intervals of 3. (Retention interval.)
  • It suggests that STM may have a short duration unless we rehearse as % of correct responses declined the longer the interval.
• Outline research on duration (LTM.)

  • Bahrick studies 392 participants from Ohio, aged 17-74.
  • Photo recognition test - 50 photos, some from participants yearbook.
  • Free recall test - recalled names of their graduating class.
  • Participants tested within 15 years of graduation were 90% accurate. After 48 years it declined to 70%. (photo recognition.)
  • 15 years 60%, dropping to 30% after 48 years. (Free Recall.)
  • This suggests LTM can last a long time.
• Evaluate Research on Coding

  • Artificial stimuli - The words had no personal meaning so we should be cautious about generalising it to other memory tasks. When processing more meaningful information, people may use semantic coding even for STM tasks. This gives it limited application.
• Evaluate research into capacity

  • Lacking validity - It was conducted a long time ago where research lacked adequate control. Some participants may have been distracted while they were being tested so they didn't perform as well as they might. Results might not be valid as there were confounding variables that weren't controlled.
  • Miller may have overestimated the capacity of STM. Other research reviewed his and concluded the capacity was only about 4 chunks.
• Evaluate Research on Duration

  • Meaningless stimuli - Peterson's material was artificial. Trying to memorise consonant syllables doesn't reflect most real life memory activities. It lacks external validity. Sometimes we do try and remember meaningless information so it isn't completely irrelevant.
  • Higher external validity - Bahrick used real-life memories. When research was conduced with more meaningless pictures, recall was lower. However, confounding variables aren't controlled as they may have looked at their yearbook over the years at different rates.
• Outline the MSM

  • It describes how information flows through the memory system.
  • Sensory register - A stimulus from the environment passes into the sensory register along with other info. This part of memory is in several stores, iconic memory (visual) echoic memory (sound coded acoustically.) Material in the SR have a high capacity. Very little of it goes into the memory system but if you pay attention it will.
  • STM - it is a limited capacity store 7+-2, info is coded acoustically and lasts about 30secs unless rehearsed. Maintenance rehearsal - rehearsing long enough shifts it to LTM.
  • LTM - This capacity is unlimited and can last for many years. It is semantically coded and transferred back into STM by retrieval.
• Evaluate the MSM

  • Supporting evidence - this shows that STM and LTM are very different. Baddeley's research. It clearly shows that coding in STM is acoustic and LTM is semantic, supporting MSM that 2 memory stores are independent.
  • There is more than one type of STM - evidence from amnesia patients shows that STM can't be a unitary store. Patient KF - STM for digits was poor when read out loud, much better when read himself. There must be different stores to process visual info and auditory.
  • There is more than one type of rehearsal - according to the MSM what matters is the amount you do. Research contradicts this, what really matters is the type of rehearsal. Maintenance rehearsal actually just maintains info in STM instead of transferring. Elaborative rehearsal is needed for LT storage. This occurs when you link the info to your existing knowledge.
• Outline types of LTM

  • Episodic - our ability to recall events, you remember when they happened and your memory of a single episode will include several elements. You have to make a conscious effort to recall episodic memories.
  • Semantic - This is our knowledge of the world (facts.) This type of memory is linked to a dictionary. It also contains your knowledge of impressive concepts.
  • Procedural - This is our memory for actions or skills. We can recall these memories without conscious awareness or a great deal of effort. These skills we may find hard to explain to someone else.
• Evaluate LTM

  • Clinical evidence - HM and Clive Wearing, episodic memory in both men was impaired by amnesia. They had difficulty recalling events. Their semantic memories weren't effected. Their procedural memories also intact. This supports Tulving than there's different memory stores.
  • Neuroimaging evidence - brain scans show different types of memory is stored in different parts of the brain. Tulving got his participants to perform memory tasks while using a PET scanner. Episodic (right)and semantic (left) recalled from the prefrontal cortex. Supports the view there's a physical reality to different types of LTM. Improving validity.
• What is the WMM

  • It is an explanation of how one aspect of memory (STM) is organised and how it functions.
  • It is concerned with the part of the part of the mind that is active when we are temporarily storing and manipulating information.
  • The model consists of 4 main components, each of which is qualitatively different especially in terms of capacity and coding.
• Outline the Central executive

  • An additional process that monitors incoming data, makes decisions and allocates slave systems to tasks, the slave systems are described below. The central executive has a very limited processing capacity.
• Outline the Phonological Loop

  • It deals with auditory information and preserves the order in which the information arrives.
  • Phonological store - stores the words you hear
  • Articulatory process - allows maintenance rehearsal (repeating sounds in a loop to keep them in working memory while they're needed.) The capacity of this loop in believed to be 2 seconds worth of what you can say.
• Outline the Visuo-spatial Sketchpad

  • This stores visual and/or spatial information when required.
  • It has a limited capacity which is 3-4 objects.
  • Visual Cache - stores visual data.
  • Inner scribe - records the arrangement of objects in the visual field.
• Outline the Episodic Buffer

  • It is a temporary store for information, integrating the visual, spatial and verbal information processed by other stores and recording events that are happening.
  • It can be seen as the storage component of the central executive and has a limited capacity of about 4 chunks.
  • It links working memory to LTM and wider cognitive processes such as perception.
• Evaluate the WMM

  • clinical evidence - Patient KF suffered brain damage. KF had poor STM ability for verbal info but could process visual info normally when presented visually. He had difficulty with sounds, phonological loop damaged. Supports existence of a separate visual and acoustic store.
  • Dual task performance - Supports the separate existence of the visuo-spatial sketchpad. Research showed participants having difficulty doing 2 visual tasks than doing both a visual and verbal task at the same time. This increased difficulty is due to both visual tasks competing for the same slave system. There must be separate slave system that processes visual input.
• Outline Interference

  • Some forgetting takes place because of interference.
  • This occurs when 2 pieces of information conflict with each other, resulting in forgetting of one or both or creating a distortion.
  • This has been proposed mainly as an explanation in LTM.
  • Once information reaches LTM is is basically permanent so any forgetting of LTM is because we can't get access to it.
  • Interference between memories makes it harder for us to locate them (forgetting.)
• Outline types of interference

  • Proactive - old memories interfere with a new one.
  • Retroactive - new memories interfere with old ones.
• Outline McGeoch and McDonald's study

  • Interference is worse when the memories are similar.
  • They studies retroactive interference by changing the amount of similarity between 2 sets of materials.
  • Participants had to learn a list of 10 words until they could remember the, with 100% accuracy, they then learnt a new list.
  • Synonyms, antonyms, words unrelated to original ones, 3 digit numbers, no new list.
  • When recalling original list, the synonyms produced the worst recall.
• Evaluate Interference Theory

  • Lab - most consistently demonstrated findings in psych, lab experiments control effects of irrelevant influence and give us confidence that interference is a valid explanation. Makes it more reliable.
  • Artificial materials - In lab not real life setting. The stimulus of words isn't realistic and not what we try and remember in real life. Can't be generalisable, may explore demand characteristics.
• Outline Retrieval Failure Theory

  • The reason people forget may be due to insufficient cues.
  • When information is initially placed in memory, associated cues are stored at the same time.
  • If these cues aren't available at the time of recall, it may make it appear as if you have forgotten the information.
  • This is actually due to retrieval failure where you can't access memories that are there.
• Outline Encoding specificity principle

  • Tulving discovered a consistent pattern to retrieval failure findings. (encoding specificity principle.)
  • This states that if there's a cue to help us recall information, it has to be present at encoding and at retrieval.
• Outline Context dependent forgetting

  • External cues
  • Godden and Baddeley
  • Divers learnt a list of words either underwater or on land and were asked to recall on both
  • In 2 of these conditions, the environmental contexts of learning and recall matched.
  • Accurate recall was 40% lower in the non-matching conditions
  • The external cues available at learning were different from the ones at recall, this led to retrieval failure.
• Outline State dependent forgetting

  • internal cues
  • Researchers gave anti-histamine drugs to participants, giving them a mild sedative effect.
  • This creates an internal physiological state.
  • The participants had to learn lists of words and passages of prose and then recall the information (created 4 conditions.)
  • Where there was a mismatch between internal state at learning and recall, performance was significantly worse.
• Evaluate retrieval failure

  • supporting evidence - increases the validity of an explanation. This is especially true when the evidence shows that retrieval failure occurs in real-life conditions as well as the highly controlled lab conditions.
  • Questioning context effects - Different contexts have to be extremely different before an affect is seen. Can't be generalised to real-life applications as this doesn't really explain much forgetting.
  • Recall v Recognition - context effect may be related to the kind of memory being tested. Godden and Baddeley replicated their experiment but instead of recall they had to see if they recognised a word. There was no context-dependent effect. The presence or absence of cues only affects memory when tested in a certain way.
• Outline Leading Questions

  • Loftus and palmer arranged for participants to watch film clips of car accidents and gave the, leading questions (how fast were the cars going when they hit each other.)
  • They changed the verb, contacted, bumped, collided, smashed.
  • The verb contacted resulted in 31.8mph while smashed produce 40.5mph.
• Why do leading questions affect EWT?

  • Response Bias - The wording of the question has no real effect on memory but influences how they decided to answer.
  • Substitution Explanation - The wording of a leading question actually changes the memory. This was demonstrated as participants who originally heard smashed were more likely to report seeing broken glass (there wasn't) than those who heard hit.
• Outline Post-Event Discussion

  • Gabbert et al, studied participants in pairs.
  • They watched a video of the same crime, but filmed from different POV.
  • Both participants then discussed what they had seen before completing a test of recall.
  • 71% of the participants mistakenly recalled aspects they didn't see but heard in discussion.
  • The control group on the other hand was 0%
  • Gabbert concluded that witnesses often go along with each other either to win social approval or because they believe the other witnesses are right and they are wrong. (Phenomenon memory conformity.)
• Evaluate Misleading Information

  • Useful real life applications - important in practical use in the real world. Consequences of inaccurate EWT can be serious. This can improve how legal systems work.
  • Artificial tasks - They watched film clips, this is different from a real accident. It lacks real stress which can influence memory. This makes the research less reliable.
  • Demand characteristics - lab study, participants don't want to let the researcher down. This limits accuracy and reliability.
• Outline the effects of anxiety

  • Anxiety has a negative effect on recall as it prevents us paying attention to important cues.
  • Johnson and Scott - lab study, sat in waiting room and they heard an argument in the next room (low anxiety condition.)
  • A man then walked through the waiting room carrying a pen with grease on his hands.
  • Other participants overheard the same heated argument but the man walked out carrying a bloody letter opener. (high anxiety.)
  • The participants then picked out a man from a set of 50 photos. 49% who saw the pen were able to identify. The letter opener condition dropped to 33%
  • The tunnel theory of memory suggests that a witness's attention narrows to focus on the weapon as it is a source of anxiety.
• Describe anxiety having a positive effect on recall

  • The stress of witnessing a crime or accident creates anxiety. This triggers the fight or flight response, increasing awareness and improving memory as we become more aware of cues.
  • Research - real-life shooting in a gun shop in Vancouver. The owner shot a thief dead. 13 witnesses agreed to take part. The interviews were held 4-5 months after the incident. These were compared to original police interviews. Accuracy was determined by the number of details reported in each account. They also rated their stress using a 7 point scale and asked about post emotional problems.
  • The witnesses were very accurate and little change in accuracy after 5 months. Those who reported the highest levels of stress were most accurate.
• Evaluate anxiety effecting EWT

  • Weapon focus may not be relevant - It may test surprise not anxiety. They focus as they are surprised not scared. Research conducted an experiment using scissors, hand gun and chicken as a hair salon. EW accuracy was poorer in conditions such as raw chicken This suggests unusualness not effects of anxiety.
  • Field studies lack control -usually interview real life witnesses after the event. Many things happen to ppts in the meantime. This suggest extraneous variables may be responsible for the accuracy of recall.
  • Ethical issues - creating anxiety is risky as it subjects them to psychological harm.
• Outline Cognitive Interviews

  • Research argued that EWT could be improved if the policed used better interviewing techniques. These techniques should be based of psychological insights into how memory works.
  • Report everything - Every single detail even if its irrelevant or not confident.
  • Reinstate the context - Should return to original crime scene (context-dependent forgetting.)
  • Reverse the order - Prevents recall of expectations and dishonesty.
  • Change perspective - Try reporting from a different POV. This disrupts the effect of schema on recall as they generate expectations.
• Evaluate Cognitive Interviews

  • Time consuming - it takes more time than standard police interviews. It also requires special training. Police aren't that impressed as its unlikely the proper version is actually used.
  • Research support - meta analysis combined data from 50 studies. CI provided more correct information than standard interviews. Real practical benefits. It gives a better chance of catching and charging criminals which benefits society.