Memory

Attachments:

• Psychopathology

1. Memory Models
   1. Multi Store Model
      1. The MSM is a structural model of memory developed by Atkinson and Shiffrin, with an emphasis on the rehearsal of information. It suggests that the STM and LTM are two unitary, singular stores. Information passes through each store in a linear process. Each store has different encoding, durations, and capacities.
      2. Information from our environment initially goes into the sensory register where it stays for about a second. We do not notice much of this stuff, but if we pay attention to it, the information will pass into our short term memory. Information can be kept here by maintenance rehearsal, but if it is further processed through elaborate rehearsal, it moves into our long term memory. The information there can then last forever.
      3. Evidence
         1. Brain damaged patients- HM had a part of his brain removed to stop his severe epilepsy. As a result, he suffered from anterograde amnesia. He could not form any new long-term memories. This showed that the STM and LTM are separate stores and that they can work independently
            1. Serial position curve- Murdock devised the serial position curve explaining the primacy and recency effect, Experiments show that when participants are presented with a list of words, they tend to remember the first few and last few words and are more likely to forget those in the middle of the list. This gave evidence for the LTM and STM stores, murdock was based his work on the MSM.
      4. The MSM is said to be oversimplistic. It places too much emphasis on the role of rehearsal and does not account for situations where we learn information instantly without rehearsing it. It is likely that semantic coding takes place in these circumstances. Additionally, research suggests that the LTM is not a unitary store, we have one store for semantic memories (factual) and a different one for procedural ones (actions). The MSM does not reflect this.
         1. The MSM does not account for more than one STM store. The case study of KF, an amnesia patient, showed that he had difficulty recalling digits read to him, but was much better at recalling when he read them. This suggests there is separate stores for visual and auditory information, which is not covered by MSM.
   2. Working Memory Model
      1. Developed by Baddeley and Hitch, the WMM replaces the idea of the unitary STM store, bases on rehearsal, as proposed by the MSM. It is an active system where mental tasks are carried out on a conscious level rather than an unconscious one, it emphasises the importance of processing. Each component has a limited capacity.
      3. The Central Executive- Modality free; most important component. It operates all the other slave systems and works independently. Its capacity is very limited.
      4. Visuo-Spatial Sketch Pad- Used to store and manipulate visual patterns and spatial movement. Undertakes mental arithmetic tasks and helps the individual to navigate.
      5. The Phonological Loop- Deals with auditory stimuli where information needs to be rehearsed to prevent decay. Contains the Phonological store; 'inner ear' (sound speech) and the Articulatory control process; 'inner voice' (verbal rehearsal).
      6. The WMM has research support. The case study of KF, an amnesia patient, showed that he had difficulty recalling digits read to him, but was much better at recalling when he read them. This suggests there is separate stores for visual and auditory information, which is showed by the WWM. His phonological loop would have been damaged.
      7. -The central executive is unfalsifiable; Richardson criticises the vague description of the CE despite it's crucial role. -There may be further stores which are not mentioned such as a musical component since we are able to listen to non-lyrical music without disrupting other stores.
      8. Episodic buffer- temporary store, integrates the visual, spatial and verbal information from the other stores together. Links to LTM.
      9. Baddeley found participants had difficulty carrying out two visual tasks at the same time, but could do a visual and verbal task at the same time. The greater difficulty is because both visual tasks compete for the same resources (VSS). This supports the different VSS and PL stores.
2. Theories of forgetting
   1. Repression
      1. Motivated forgetting where emotionally threatening and traumatising events/memories are thought to be banished from our LTM into the unconscious mind to avoid re-experiencing the anxiety it may cause.
         1. Williams investigated women who had suffered childhood sexual assaults. 38% had no recall of events, 16% reported they hadn't once been able to.
   2. Interference
      1. Interference- Forgetting occurs when one memory blocks another, causing one or both to become distorted or forgotten.
      2. Retroactive interference- where NEW information interferes with the ability to recall OLDER information.
      3. Proactive interference- where OLDER information interferes with the ability to recall NEW information.
      4. Underwood & Postman- supported retroactive interference; gave groups lists of word pairs such as cat-tree. One group had to learn one list, one had to learn two. Both had to recall the first. Recall was worse for the group that learnt two lists.
      5. Most research is lab based, providing evidence for both types of interference whilst keeping control of extraneous variables to improve validity.
         1. However, artificial materials are used. The material is often word lists or groups of numbers, which is different to day-to-day remembering. This may make interference way more likely due to the individual not being interested in it.
      6. Interference is worse when memories are similar.
         1. McGeoch and McDonald- Participants had to learn a list of 10 words until they could remember with 100% accuracy. They then learned a new list, in 6 different groups all learning different types of lists. 1: synonyms. 2: Antonyms. 3: related words. 4: nonsense syllables. 5.three-digit numbers. 6: no list, rest. Participants recall depended on the nature of the second list- similar material produced the worst recall (synonyms). Shows interference is strongest when memories are similar.
      7. Baddeley and Hitch asked rugby players to recall names of teams they had played so far, week by week. Accurate recall did not depend on how long ago the match was, but the number of games played in the meantime. This applies to everyday situations.
   3. Cue Dependency
      1. Context dependent- Occurs with external retrieval cues; the environment is different at recall to when the material is learnt.
         1. Godden & Baddeley- Divers learnt information either on dry land or underwater, and then recalled it either on land or underwater. Recall was found to be 40% worse when the recall context was different to the environment in which it was learnt, compared to when the environment was kept the same. This demonstrates context-dependent forgetting because information wasn't retrievable when the environment did not match.
      2. State dependent- Occurs with internal retrieval cues; internal environment is different at recall than to when the material was learnt.
         1. Darley- found participants who hid money while high were less able to recall where the money was when they were then not high, compared to when they were high again.
      3. When information is placed in the memory, associated cues are stored at the same time. If these cues aren't available at the time of recall, you may not be able to retrieve the information.
      4. Baddeley argued that different contexts have to be very different indeed before an effect is seen (i.e land vs water). Learning something in one room and recalling it in another is unlikely to result in forgetting. Therefore real life applications may be weak and don't actually explain much forgetting.
      5. Godden and Baddeley replicated their underwater experiment but using a recognition test rather than recall. There was no context-dependent effect. Performance was the same over all conditions. This limits retrieval failure as an explanation because it only affects memory when testing recall rather than recognition.
         1. A strength is that there are real life applications. People often report going downstairs to get an item but then forgot what they came downstairs for. They then go back upstairs and remember again. This suggests that when we have trouble remembering something, we should revisit the environment in which we experienced it. This can be applied to the cognitive interview. Eyewitnesses are told to reinstate the context when recalling events so that their memory is jogged by environmental cues.
3. Eye witness testimonies
   1. Misleading information
      1. Post event discussion
         1. When co-witnesses discuss a crime, they mix (mis)information from the other witnesses with their own. Witnesses go along with each other to win social approval or because they believe the other witnesses are right.
         2. Gabbert et al. - Participants were asked to watch videos of a crime, but filmed so each participant saw different parts than the other. Both then discussed what they saw afterwards before completing a test of recall. 71% of participants mistakenly recalled parts of the video that they did not see but instead picked up in the post-event discussion. In the control group with no discussion, there was no errors.
      2. Leading questions
         1. Leading questions do two things: The wording of the question has no enduring effect on an eyewitness' memory of an event, but influences the kind of answer given, or the wording of the question does affect eye witness memory and interferes with the original memory, distorting its accuracy.
         2. Loftus and Palmer- 45 university students watched film clips of car accidents and then answered questions about speed. Critical question: 'How fast was the car going when it hit the other car?' The participants were split into 5 groups, with the verb changing between each; hit, contacted, bumped, collided or smashed. Powerful words like smashed gave on average higher speed estimates (40.5) and softer ones such as contacted gave on average lower speed estimates (31.8). The leading verb biased the eyewitness recall of the event.
         3. Has good real-life applications. The research has led to important practical uses for police officers and investigators because the consequences of inaccurate EWT can be very serious. This has led to an improvement in the interviewing system of EWT.
            1. Loftus and Palmer used artificial materials. Watching a film clip of an accident it very different to witnessing a real accident in real life. Yuille and Cutshall argued that anxiety has an important role in remembering events. When watching a clip, we are alert and focused on details, whereas in real life, we are impacted by stress and fear which could impact our memory. This makes application difficult.
               1. Lacks external validity. What an eyewitness can remember in real life situations can have important consequences such as a successful conviction. This is not true for research studies, where they may put less effort into trying to remember.
               2. Suffers demand characteristics. Participants want to be helpful and attentive. So when asked a question they don't know the answer to, they guess. This challenges the validity of EWT research.
   2. Anxiety
      1. Anxiety has strong emotional and physical effects. But it is not clear whether these effects make eyewitnesses' recall better or worse.
         1. Yerkes-Dodson curve explains a curvilinear relationship where a level of anxiety can increase accuracy of EWT, but as anxiety continues to increase accuracy will fall.
         2. Anxiety has positive effect
            1. Yuille and Cutshall- 13 witnesses of a real life crime of a gun-shop owner in Canada, were interviewed 4-5 months after the incident and rated how stressed they were when it happened. Witnesses were very accurate and there was little change after 5 months. Those who experienced the highest levels of anxiety were most accurate (88% compared to 75%).
               1. Field studies lack control of variables. Real life witnesses are interviewed some point after the event. Many things happen to them in the meantime that researchers cannot control. For example, discussing with other eyewitnesses, read accounts or see images through the media, etc. These variables may be responsible for the accuracy of recall.
                  1. Demand characteristics- participants are aware they are watching a film for a reason to do with a study. They may work out that they will be asked questions about what they have seen and so may pay extra attention to details or give responses which they believe will be helpful.
               2. Creating anxiety in participants is potentially unethical because it may subject people to psychological harm. Ethical issues don't challenge the findings of studies, but they do raise concerns about conducting the research. So real-life studies are beneficial because the participant has already witnessed the event.
         3. Anxiety has negative effect
            1. Loftus explained the weapons focus effect, whereby a person focuses on the weapon involved when in a crime and therefore ignores any other details.
            2. Johnson & Scott- Participants sat in a waiting room believing they were about to take part in a lab study. Participants heard an argument in the next room; low-anxiety condition: participants then saw a man walk through the waiting room carrying a pen with grease on his hands; high anxiety condition: participants heard the sound of breaking glass and then a man walked through the waiting room with a bloodied knife. 49% of participants in the low anxiety condition could correctly identify the man, 33% of participants could identify him in the high anxiety condition. Participant's focus was on the source of danger and not the man's face. Showing anxiety worsened their memory.
               1. May have tested surprise not anxiety. Participants may focus on the weapon because they are surprised by it rather than because they're scared. Pickle used scissors, a handgun, a wallet and raw chicken as hand-held items in a hairdressing salon. EWT accuracy was worse for high unusualness (chicken and handgun). The weapon focus effect may be due to unusualness rather than anxiety/threat.
   3. Cognitive interviewing
      1. Fisher and Geiselman claim that EWT could be improved if the police use techniques based on psychological insights of how the mind works. It is based on cognitive psychology.
      2. Report everything: every detail of the event, even if it seems irrelevant or the witness is not confident about it.
      3. Reinstate the context: Witnesses return to the scene 'in their mind' by describing the environment (weather, smells and emotions.)
      4. Reverse the order- Events are recalled in a different chronological order (e.g from end to beginning or from the middle to beginning) this prevents them using their expectations of how things would have happened.
      5. Change perspective- witnesses recall the event from other people's point of view and perspectives.
      6. Holliday- children ages 4-5 and 9-10 watched a 5 min video of a child's birthday party, and were interviewed the next day about it using either SPI or CI. CI produced more accurate details than SPI.
      7. It's time consuming. Police are reluctant to use CI over standard interviewing because it takes up much more valuable time. Additionally, it also requires special training which is limited by time and money. This makes it unlikely that a proper, full version of CI is used.
      8. Studies of the effectiveness of CI inevitably use slightly different techniques. Different researchers may use variations of CI and involve their own methods. This reduces our ability to draw conclusions due to poor reliability.
4. Types of Memory
   1. Coding, capacity and duration
      1. CAPACITY STM- 7+/-2
         1. Miller- made everyday observations. Found people remembered things in sevens, noted 7 days of the week and 7 notes on a musical scale etc.
      2. CAPACITY LTM- UNLIMITED
      3. CODING STM- ACOUSTIC
         1. Baddeley- Groups had to recall either acoustically similar or dissimilar words or semantically similar or dissimilar words. Acoustically similar words recalled worst instantly and semantically similar recalled worst after 20 mins.
      4. CODING LTM- SEMANTIC
      5. DURATION STM- 18-30s.
         1. Peterson and peterson- students were given a consonant syllable (YCG) to remember and a 3 digit number to count backwards from for either 3,6,9,12,15 or 18 seconds. 80% were recalled after 3s. 3% recalled after 18s.
      6. DURATION LTM- LIFETIME
         1. Bahrick- Participants had to recall names from their graduating class using free recall and photo recognition. 48 years later photo recognition was still 70% accurate.
      7. Baddeley's study didn't use meaningful material. when processing meaningful info, people may use semantic coding even for STM tasks. It therefore has limited applications.
      8. Miller's research may have overestimated the capacity. Cowan reviewed other research and concluded the capacity was more like 4 chunks.
      9. Peterson and Peterson is artificial. memorising consonant syllables does not reflect real life memory activities, where we often memorise more meaningful things.
      10. Bahrick has high external validity. Real life, meaningful memories (people's faces and names) were studied.
   2. LONG TERM
      1. Declarative
         1. Things we 'know that'.
         2. Episodic: Gives an individual an autobiographical account of personal experiences e.g birthdays. Helps individuals distinguish between real life events and imagined events. It is influenced by emotion at the time the memory was encoded.
            1. -The extent to which episodic and semantic memories are different is unclear, as although different brain areas are involved, there is a lot of overlap in which semantic memories originate from episodic ones. Cohen and Squire argued that there are two types of LTM- declarative and non-declarative, meaning semantic and episodic memories are stored together the same way, and procedural is a distinctly different type, stored differently.
               1. Tulving- had participants perform memory tasks whilst having a PET scan. Episodic and semantic memories were both in the prefrontal cortex but semantic was to the left, and episodic to the right. This shows the physical reality in the different LTM types.
         3. Semantic: contains all knowledge (facts, concepts and meanings) a person has learnt. It is less personal and more about knowledge people share. Often linked to episodic LTM's as new knowledge tends to be learnt from experiences.
            1. -May involve more of a network of associated links performed in different brain areas, rather than a single form of memory ability. Some links may be stronger than others explaining why some are easier to recall than others..
               1. Vicari et al. Case study of CL- an eight year old girl who suffered from brain damage due to the removal of a tumour. She demonstrated deficiencies in her episodic memories, but was still able to create and recall semantic ones.
      2. Non-declarative
         1. Things we 'know how' to do
         2. Procedural: Occur mainly in early life involving important motor skills such as talking, walking and dressing. It allows individuals to carry out learnt tasks with little to none thought - we remember without conscious awareness.
            1. -There is lack of case studies of people with brain damage that affects procedural memory but not declarative memory, meaning there is a lack of supporting evidence. - Procedural memories take longer to learn than declarative memories. this may be due to the involvement of motor functions and spatial abilities that declarative memories tend not to include.
               1. Finke et al. case study of PM, a 68 year old professional musician who suffered from brain damage resulting in amnesia. His episodic and semantic LTM were affected, his procedural was not effected and he could still play musical instruments.