memory

• Sensory register duration


  Less than half a second and up to 2 seconds.
• sensory register capacity


  very large
• STM capacity


  7 +/- 2
• STM coding


  Acoustically
• STM duration


  18-30 seconds
• LTM capacity


  virtually unlimited
• LTM duration


  Up to a lifetime
• LTM coding


  semantic
• Strength for MSM - Research support for STM capacity

  Jacobs - Digit span task - presented sequence to participants and made them recall completely accurately. Each time ppt could correctly recall sequence, another number was added until ppt could no longer successfully recall the sequence (otherwise known as participant digit span task)

  
  

  Number = 7.3 , Letter = 9.3
• Strength for MSM - Research support for LTM duration

  Bahrick - asked participants to identify those who were genuinely in their year group in pictures of 50 people, some of which were not members of their year group.

  
  

  15 years = around 90% accuracy.

  48 years = around 70% accuracy.
• Refuting evidence for MSM being unitary

  Clive wearing contracted a viral infection that led to a great amount of brain damage. As a result of this brain damage, CW lost his long term declarative memory (no memory of his wedding) but his procedural memory remained , as he was able to play piano still.

  
  

  - if ltm was unitary as theory suggests, he would have lost both functions.
• Strength for STM and LTM coding

  Baddeley - gave ppts list of either semantically similar or acoustically similar words and asked them to recall.

  Acoustic- immediately - found that there was poor recall

  Semantically - after 20 minutes, show poor recall of words.
• WMM components


  central executive, phonological loop, visuo-spatial sketchpad, episodic buffer
• central executive


  Delegates tasks to slave components.

  - deals with higher mental processes such as decision making.

  - Allocates resources to slave components based on importance.
• phonological loop components


  1- PAS 2- AP
• Primary acoustic store (PAS)


  Linked to speech perception.

  - duration is for 1-2 seconds and remembers sounds in the same order that they were presented.
• Articulatory process (AP)


  Linked to speech production.

  - Used to rehearse and store sounds collected by the PAS.

  - can hold up to 2 seconds of speech.
• Visuo-spatial sketchpad (VSS) components

  Visual Cache and Inner Scribe
• Visual cache


  Stores visual information about form and colour
• Inner scribe


  active store handling spatial relations.
• episodic buffer


  Takes information from both stores and integrates them together.

  Has limited capacity of 4 chunks of information.
• WMM strength 1


  Baddeley and Hitch - ppt could do different tasks that take up capacity in DIFFERENT stores. Recall is unaffected when asked to do verbal task in AP and separate task in CE. But two SIMILAR tasks = affected recall.
• WMM strength 2


  Supporting research from brain scans.

  
  

  Cohen et Al - found that when completing verbal tasks, there was increased activity in Brocis Area- associated with auditory tasks.

  Visual tasks - occipital lobe - associated with visual tasks.

  
  

  1 - Provides physical evidence for the existence of VSSP and PL.

  2- Shows that VSSP does play role in visual, PL plays in verbal.
• WMM weakness 1


  There is refuting evidence for the unitary view of the CE.

  
  

  Case study EVR had tumour removed. Performed well on tests requiring reasoning which suggests an in-tact central executive as it controls higher function but poorly on decision-making tasks (choosing where to eat).

  - If CE was truly unitary, then ......
• WMM weakness 2


  Berz - musical memory
• Types of Long term memory

  Declarative (episodic and semantic) and procedural
• Episodic memory


  - Are timestamped

  - The ability to remember personal experiences.

  - Requires conscious effort to recall.

  - Strength of memory depends on emotion present at time of coding.
• Semantic memory


  NOT timestamped.

  - Include facts/ knowledge about the world

  - Requires conscious effort to recall.
• Procedural memory


  Do not require conscious effort to recall.

  - Memory for action motor skills such as walking.

  - Many are formed early in life.
• LTM Strength


  Neuro-imaging evidence.

  TULVING ET AL - Various memory tasks while in a PET scan.

  Episodic memory tasks - pre-frontal cortex was most active.

  Semantic memory tasks - Posteror region most active,
• LTM strength 2


  BELLEVILLE ET AL - Has practical application.

  Episodic memory = type of memory most affected by mild cognitive impairments such as memory loss in elderly, which highlights importance of being able to distinguish between types of LTM.

  
  

  BELLEVILLE ET AL - demonstrated that episodic memory could be improved in elderly w mild cognitive impairments. Found thru the trained group's better performance in episodic memory task.
• LTM strength 3


  CASE STUDY - Clive Wearing - lost declarative (memories of wedding) but kept procedural (knew how to play piano). SHE
• LTM weakness


  It is hard to draw the line/ distinguish between episodic and semantic memories. Episodic memories are a GATEWAY to forming semantic memories. EG- facts can originate in episodic memories.
• Proactive interference

  When retention of old information disrupts the recall of new information.
• Retroactive interference


  When retention of new information disrupts the recall of old information.
• Effect of similarity in Interference

  When sets of memory information are more similar, interference is more likely to occur.
• AO1 for Interference Theory

  Postman- gave ppts list of word-pairs to learn and asked them to recall. E.g. cat-tree

  Experimental group- given a 2nd list to learn , where 2nd word was different to original word pairs. E.g - cat-glass.

  Control group = NO 2ND LIST.

  Control group performed better due to experimental group having gone thru retroactive interference.
• Strength of interference theory

  Supporting evidence for the role of similarity.

  
  

  MCGEOCH + MCDONALD - gave diff groups 2 different lists. One group's second list consisted of synonyms of first list. Another group = nonsense syllables such as XUA.

  Nonsense syllable = 26% , Synonym = 12%

  - Supports theory as you're more likely to experience interference when sets of memory information are similar
• Strength of interference theory

  Practical application - DANAHER ET AL

  
  

  DANAHER found that both recall and recognition of an advertisers message were impaired when exposed to 2 different adverts within a short period of time.

  As a result, DANAHER suggested that rather than spreading out their adverts sporadically over a week, they should instead do MULTIPLE adverts in one day.

  - Not purely theoretical.
• Weakness of Interference theory

  Research it relies on is artificial - artificial lab experiments, where interference requires special conditions like word pair stimuli. Not day-day activity. - only accounts for a very specific and limited range of instances of forgetting in the LTM.