Psychology: Memory

• Coding


  The type of format of information being stored
• Coding


  1. Study - Baddeley - participants given 1 of 4 word lists to learn (semantically/ acoustically similar/dissimilar)

  2. More confusion with acoustically similar in STM recall, more confusion with semantically similar in LTM recall

  3. STM - coded acoustically (sound) , LTM - coded semantically (by meaning)
• Capacity


  The quantity of information stored
• Capacity


  1. Study - Jacobs- participants given a number of letters/digits and asked to recall

  2. 9.3 digit span, 7.3 letter span

  3. Miller noticed lots of things come in 7s

  4. Concluded that people can recall 7 chunks of information, + or - 2
• Duration


  The length of time information is held for
• Duration


  1. STM - Peterson & Peterson. 24 students were shown trigrams, then asked to count backwards from a 3 digit number from a set amount of time

  2. STM lasts about 18-30 seconds without rehearsal

  3. LTM- Bahrick et al. Highschool yearbooks. 15 years after graduation- 90% facial recognition, 60% name recall. 48 years after graduation - 70% faces, 30% names

  4. LTM can potentially last forever
• Short term memory (STM)


  • The limited capacity memory store
  • Coding is mainly acoustic (sounds)
  • Capacity is between 5 and 9 items on average
  • Duration is about 18 seconds
• Long term memory (LTM)


  • The permanent memory store
  • Coding is mainly semantic (meaning)
  • Unlimited capacity
  • Can store memories up for a lifetime
• Types of long term memory


  • Episodic - memory of personal events
  • Semantic - knowledge of the world
  • Procedural - knowledge of how to do things
• Multi store model of memory

  • Explanation of memory proposed by Atkinson & Shiffrin
  • Sensory register - split into iconic (visual), echoic (auditory), and other memory stores
  • Input information from the environment
  • High capacity, short duration
  • STM- information transferred to STM if we pay attention to it
  • Maintenance rehearsal keeps information in the STM
  • LTM- prolonged/ elaborative rehearsal takes information from STM to LTM
  • To recall information it must go back to the STM before we can remember it
• Sensory register


  • The memory stores for each of our five senses, such as vision (iconic store) and hearing (echoic store )
  • Coding in the iconic sensory register is visual and in the echoic sensory register it is acoustic (sounds)
  • The capacity of sensory registers is huge (millions of receptors) and information lasts for a very short time (less than half a second )
• Episodic memory


  • A long term memory store for personal events
  • It includes memories of when the event occurred and of the people, objects, places and behaviours involved
  • Memories from this store have to be retrieved consciously and with effort
  • It is "Time - stamped" you remember when they happened as well as what happened
• Semantic memory


  • A long term memory store for our knowledge of the world
  • This includes facts and your knowledge of what words and concepts mean
  • These memories usually also need to be recalled deliberately
  • These memories are not "time - stamped"
• Procedural memory


  • A long term memory store of our knowledge of how to do things
  • This includes our memories of learned skills
  • We usually recall these memories without making a conscious or deliberate effort
• Working memory model


  • A representation of short-term memory (STM)
  • It suggests that STM is a dynamic processor of different types of information using subunits co-ordinated by a central decision-making system
• Central executive


  • The component of the WMM that coordinates the activities of the three subsystems in memory
  • It also allocates processing resources to those activities
  • Monitors incoming data, focuses and divides our limited attention
  • The CE has a very limited processing capacity and does not store information
• Phonological loop


  • The component of the WMM that processes information in terms of sound
  • This includes both written and spoken material
  • It's divided into the phonological store (stores the words you hear) and the articulatory process (allows maintenance rehearsal, repeating sounds or words in a "loop" to keep them in working memory while they are needed)
  • The capacity of this loop is believed to be 2 seconds worth of what you can say
• Visuo-spatial sketchpad


  • The component of the WMM that processes visual and spatial information in a mental space often called our 'inner eye'
  • It also has a limited capacity, which according to Baddeley (2003) is about three or four objects
  • Robert Logie (1995) subdivided the VSS into the visual cache (which stores visual data) and the inner scribe (which records the arrangement of objects in the visual field e.g how many windows they are in your house)
• Episodic buffer


  • The component of the WMM that brings together material from the other subsystems into a single memory rather than separate strands
  • It also provides a bridge between working memory and long term memory
  • It is a temporary store for information, integrating the visual, spatial, and verbal information processed by other stores and maintaining a sense of time sequencing
  • It can be seen as the storage component of the central executive and has a limited capacity of about four chunks (Baddeley 2012)
  • The episodic buffer links working memory to long-term memory and wider cognitive processes such as perception
• Interference


  • Forgetting because one memory blocks another, causing one or both memories to be distorted or forgotten
  • This occurs when two pieces of information disrupt each other
  • Interference has been proposed mainly as an explanation for forgetting in LTM
• Proactive interference


  • Forgetting occurs when older memories, already stored, disrupt the recall of newer memories
  • The degree of forgetting is greater when the memories are similar
• Retroactive interference


  • Forgetting occurs when older memories, already stored, disrupt the recall of newer information
  • The degree of forgetting is greater when the memories are similar
• Effects of similarity


  1. McGeoch and Mcdonald (1931) studied retroactive interference by changing the amount of similarity between two sets of materials

  2. Participants had to learn a list of 10 words until they could remember them with 100% accuracy

  3. They then learned a new list with different types of words

  4. The most similar material (synonyms) produced the worst recall

  5. This shows that interference is strongest when the memories are similar
• Retrieval failure


  • A form of forgetting that occurs when we don't have the necessary cues to access memory
  • The memory is available but not accessible unless a suitable cue is provided
• Cue


  • A 'trigger' of information that allows us to access a memory
  • Such cues may be meaningful or may be indirectly linked by being encoded at the time of learning
  • Indirect cues may be external (environmental context) or internal (mood or degree of drunkenness)
• Encoding specificity principle


  • If the cue is to help us to recall information it has to be present at encoding (when we learn the material ) and retrieval (when we recall it)
  • If the cues available at encoding and retrieval are different there will be some forgetting
  • Some cues are linked to the material to be remembered in a meaningful way, used in mnemonic techniques
  • Other cues are also encoded at the time of learning but not in a meaningful way
• Research on context-dependant forgetting


  1. Godden & Baddelely (1975) carried out a study of deep sea divers working underwater

  2. Divers learned a list of words either underwater or on land

  3. Accurate recall was 40% lower in the non- matching conditions

  4. They concluded that the external cues available at learning were different from the one available at recall and this led to retrieval failure
• Research on state- dependent forgetting


  1. Sara Carter and Helen Cassaday (1998) gave antihistamine drugs(for treating hay fever) to their participants

  2. Participants had to learn a list of words and passages of prose and then recall the information again
• Learn on land - recall on land


  Learning and recall occur in the same environmental context
• Learn on land - recall underwater


  Learning and recall occur in different environmental contexts
• Learn underwater- recall on land


  Learning and recall occur in different environmental contexts
• Learn underwater - recall underwater


  Learning and recall occur in the same environmental context
• Accurate recall was 40% lower in the non- matching conditions
• The external cues available at learning were different from the one available at recall and this led to retrieval failure
• State-dependent forgetting


  Forgetting that occurs when the internal state (e.g. drug effects) at learning and recall do not match
• State-dependent forgetting study


  1. Learn on drug

  2. Recall on drug

  3. Learn not on drug

  4. Recall not on drug
• Performance on the memory test was significantly worse when there was a mismatch between internal state at learning and recall
• When the cues are absent (e.g you are drowsy when recalling information but had been alert learning it) then there is more forgetting
• Retrieval failure explanation for forgetting


  • Supported by a range of research
  • May be the main reason for forgetting from long-term memory
• Eyewitness testimony (EWT)


  The ability of people to remember the details of events, such as accidents and crimes, which they themselves have observed