capacity

• What is the capacity of short-term memory according to Miller's theory?


  7±2 items
• What does the digit span test measure?


  It measures the capacity of short-term memory
• What was the main task participants had to perform in the digit span test?


  Recall a sequence of digits in the same order, increasing string length each time
• What did Miller and other psychologists conclude about short-term memory capacity?

  Only a few items can be held in short-term memory at any one time
• What did Cowan's findings suggest about the theory of short-term memory capacity?


  found we could only remember 4 items, suggesting that the theory may not be valid for all information processing
• How does the theory of short-term memory capacity apply to real-world situations?


  It explains why it's hard to remember many items, like credit card numbers
• What is the capacity of long-term memory thought to be?


  Unlimited
• What is a major difficulty in testing long-term memory (LTM)?


  The duration of memory retention is hard to measure
• What are the capacities of different types of memory?

  • Sensory memory: Vast
  • Short-term memory: Limited (7±2 items)
  • Long-term memory: Unlimited
• Can you devise an experiment to test the capacity of long-term memory?


  No, it is difficult to measure
• What is a key factor to consider when testing long-term memory?


  Whether the information was learned in the first place
• jacobs 1887

  • capacity in short term memory story
  • digit span test
  • when participants fail on 50% of trials, they have reached their digit span capacity
  • used free recall technique
• jacobs 1887- findings

  • on average, recalled 7 and 9 letters
  • average recall increased with age
  • digits mean span- 9.3
  • letters mean span- 7.3
  • stm has a limited storage capacity of between 5-9 items memory techniques may.
  • learned memory techniques may increase capacity as people get older.
• jacobs 1887- criticisms

  • 26 letters but only 0-9 digits, meaning letters are harder to recall as there are more.
  • conducted in 1887, meaning may not of had control in experiment- lack of control of extraneous variables
• define chunking 


  grouping information may help to improve memory capacity