Memory and State dependence 1

Question 1

how did Hermann Ebbinghaus discover the forgetting curve?

Answer 1

• used nonsense syllables (e.g. CVC)
• the sequence of them would have no pre-existing associations
• Used himself as the participant and completed serial learning tasks
• he used the method of savings
• developed a curve: forgetting was initially rapid then levels off (see onenote for graph)

Question 2

forgetting in rats by excitatory conditioning, Hendersen (1985)

Answer 2

• conditioned suppression of licking in rats using the US of a shock
• irrespective of US intensity, hardly any forgetting after 60 days
• so memory traces can last 60 days (see graph on OneNote)

Question 3

forgetting in rats by inhibitory conditioning, Hendersen (1985)

Answer 3

• fear conditioning procedures with the US being a shock: B is excitatory shock, X is the trained inhibitor
• so in a more complex learning situation some forgetting can be seen in 35 days (see graph on OneNote)

Question 4

Forgetting can be reduced by a reminder, Gordon et al., (1979)

Answer 4

• used an avoidance learning procedure (CS will learn to a shock)
• relatively high latencies show forgetting tested 3 days later
• memory performance improved by a reminder (apparatus CS exposure 24 hr or 10 min prior to test)
  see graph on OneNote

Question 5

Krechevsky maze, Deweer & Sara (1984)

Answer 5

• rapid learning of the maze was shown to decrease the number or errors made
• forgetting was tested 25 days later
• experimenter gave cues to rats of varying lengths of either 0, 10, 30, 90 or 300 seconds using extra maze cues
• memory performance restored by a reminder of 90 seconds prior to test
  see graph on OneNote

Question 6

what are trace decay theories?

Answer 6

• all memories fade automatically as a function of time
• information storage is reflected by physical changes in the brain, in absence of rehearsal these memory traces become weaker with time
• cells that fire together, wire togther

Question 7

strengths of trace decay theories?

Answer 7

• describes the forgetting curve well
• it is simple

Question 8

limitations of trace decay theories?

Answer 8

• assumes that forgetting is equal to memory erasure
• if a trace “disappears” (or weakens), then memory is not there
• fails to explain the effect of reminders

Question 9

what is the inference theory? (McGeoch, 1932)

Answer 9

• he argued that human theory is fundamentally associative
  -recall is guided by cues or stimuli to which items in memory are associated
• because a given individual may have various experiences multiple items may become associated with the same cue

Question 10

what is proactive interference?

Answer 10

old memories affecting the formation of new memories

Question 11

what is retroactive interference?

Answer 11

new memories affecting the recall of older memories

Question 12

what are some theoretical implications of experimental observations?

Answer 12

• memories can last longer than you think if trace decay were the cause of forgetting
• the fact that reminders can jog memories can be forgotten without necessarily having decayed
• temporary retrieval problems point to the importance of interference as a cause of forgetting
• associative learning can explain how reminders work

Question 13

context-dependent memory, Godden and Baddeley (1975)

Answer 13

• learnt a list of words either on land or underwater
• test condition either on land or in water
• memory was better if tested in same context as where it was learned

Question 14

encoding specificity Tulving and Thomson (1973)

Answer 14

• encoding in context provides memory triggers
• category names (e.g., animals) for word lists (e.g., cow, rat, etc)
• effective cues enable the retrieval of items that would not be retrieved under non-cued recall conditions (Tulving and Pearlstone, 1966)