1. Long-Term Memory: Encoding and Retrieval
Chapter 7
Long-Term Memory: Encoding and Retrieval

2. Some Questions to Consider
What is the best way to store information in long-term memory?
What are some techniques to help us get information out of LTM when we need it?
How can the results of memory research be used to create more effective study techniques?
How is it possible that a lifetime of experiences and accumulated knowledge can be stored in neurons?

3. Storing Information in LTM
Encoding: acquiring information and transforming it into memory
Maintenance rehearsal
Maintains information but does not transfer it to LTM
Elaborative rehearsal
Transfers information to LTM

4. Levels of Processing Theory
Memory depends on how information is encoded
Depth of processing
Shallow processing: little attention to meaning (poor memory)
Deep processing: close attention to meaning (good memory)

5. Caption: (a) Sequence of events in Craik and Tulving’s (1975) experiment. (b) Results of this experiment. Deeper processing (fill-in-the-blanks question) is associated with better memory.

6. Beware of Circular Reasoning!
Which task causes deeper processing?
Using a word in a sentence
Deciding how useful an object might be on a desert island
Can empirically measure the memory trace in each condition
Conclude that stronger memory trace must have been caused by deeper processing
But depth of processing has not been defined independently of memory performance
Therefore, this is circular reasoning

7. Caption: The circularity of defining depth of processing in terms of memory and then predicting that deeper processing will result in better memory.

8. Other Factors that Aid Encoding
Imagery
Creating connections, cues for remembering
Self-reference effect
Generation effect
Organizing to-be-remembered information
Testing

9. Organization, Comprehension, and Memory
Bransford & Johnson (1972)
Presented participants with difficult-to-comprehend information
Experimental Group 1 first saw a picture that helped explain the information
Experimental Group 2 saw the picture after reading the passage
Control Group did not see the picture
Group 1 outperformed the others.
Having a mental framework of comprehension aided memory encoding and retrieval

10. Caption: Picture used by Bransford and Johnson (1972) to illustrate the effect of organization on memory.

11. Which results in a stronger memory trace?
Testing Effect
Which results in a stronger memory trace?
Re-reading the material
Being tested on the material
Roediger and Karpicke (2006) had participants read a passage and then either
Recall as much as they could
Reread the passage
Tested recall after a delay

12. Caption: Results of the Roediger and Karpicke (2006) experiment
Caption: Results of the Roediger and Karpicke (2006) experiment. Note that at longer times after learning, the performance of the testing group is better than the performance of the rereading group.

13. Retrieving Information from LTM
Retrieval: process of transferring information from LTM back into working memory (consciousness)
Most of our failures of memory are failures to retrieve

14. Retrieving Information from LTM
Cued-recall: cue presented to aid recall
Increased performance over free-recall
Retrieval cues most effective when created by the person who uses them

15. We learn information together with its context
Encoding Specificity
We learn information together with its context
Baddeley’s (1975) “diving experiment”
Best recall occurred when encoding and retrieval occurred in the same location

16. Caption: (a) Design for Godden and Baddeley’s (1975) “diving” experiment. (b) Results for each test condition are indicated by the bar directly under that condition. Asterisks indicate situations in which study and test conditions matched.

17. Caption: (a) Design for Grant et al. ’s (1998) “studying” experiment
Caption: (a) Design for Grant et al.’s (1998) “studying” experiment. (b) Results of the experiment. Asterisks indicate situations in which study and test conditions matched.

18. State-Dependent Learning
Learning is associated with a particular internal state
Better memory if person’s mood at encoding matches mood during retrieval

19. Caption: (a) Design for Eich and Metcalfe’s (1989) “mood” experiment
Caption: (a) Design for Eich and Metcalfe’s (1989) “mood” experiment. (b) Results of the experiment.

20. Improving Learning and Memory
Elaborate
Highlighting is not enough!
Generate and test
Organize
Helps reduce load on memory
Match learning and testing conditions

21. Improving Learning and Memory
Associate what you are learning to what you already know
Avoid the “illusion of learning”
Familiarity does not mean comprehension
Take breaks
Memory is better for multiple short study sessions
Consolidation

22. Improving Learning and Memory
Distributed versus massed practice effect
Difficult to maintain close attention throughout a long study session
Studying after a break gives feedback about what you already know

23. Information Storage at the Synapse
Hebb (1948)
Learning and memory represented in the brain by physiological changes at the synapse
Neural record of experience

24. Information Storage at the Synapse
Long-term potentiation (LTP)
Enhanced firing of neurons after repeated stimulation
Structural changes and enhanced responding

25. Caption: What happens at a synapse as (a) a stimulus is first presented. The record next to the electrode indicates the rate of firing in the axon of neuron B. (b) As the stimulus is repeated structural changes are beginning to occur. (c) After many repetitions, more complex connections have developed between the two neurons, which causes an increase in the firing rate, even though the stimulus is the same on that was presented in (a).

26. Where Does Memory Occur in the Brain?
Medial temporal lobe
Hippocampus
Perirhinal cortex

27. Caption: (a) Side view of the brain and (b) underside of the brain, showing the amygdala and structures in the medial temporal lobe (perirhinal cortex, parahippocampal cortex, entorhinal cortex, and hippocampus).

28. The Fragility of New Memories
Retrograde amnesia: loss of memory for events prior to the trauma
Anterograde amnesia: cannot form new memories
Memory for recent events is more fragile than for remote events

29. Transforms new memories from fragile state to more permanent state
Consolidation
Transforms new memories from fragile state to more permanent state
Synaptic consolidation occurs at synapses, happens rapidly
Systems consolidation involves gradual reorganization of circuits in brain

30. Standard model of consolidation
Retrieval depends on hippocampus during consolidation; after consolidation hippocampus is no longer needed
Reactivation: hippocampus replays neural activity associated with memory
Controversial

31. Caption: (a) According to the standard model of consolidation, retrieval of recent memories depends on the hippocampus; cortical connections have not yet formed. Thus, for retrieval of recent memories, hippocampal activation is high and cortical activation is low. (b) Once consolidation has occurred, cortical connections have formed, and the hippocampus is no longer needed. Thus, for retrieval of remote memories, cortical activation is high, and there is no hippocampal activation.

32. Multiple trace hypothesis
Consolidation
Multiple trace hypothesis
Questions the assumption that the hippocampus is important only at the beginning of consolidation
the hippocampus has been shown to be activated during retrieval of both recent and remote memories (Gilboa et al., 2004)

33. Are Memories Ever “Permanent”?
Reactivation and reconsolidation evidence from research on animals
Occurs under certain conditions
Human memory is a “work in progress”