PSY 323: Cognition Chapter 7: Long-Term Memory: Encoding, Retrieval, & Consolidation

Encoding Mental Rehearsal Maintenance Rehearsal Elaborate Rehearsal Repeating things over and over Helps maintain information in STM/WM Elaborate Rehearsal Involves thinking about how new material relates to information already stored in memory Effective at transferring information into LTM

Levels of Processing (LOP) Craik & Lockhart (1972); Nairne (2010) Quality of memory depends on how information is encoded See demo on next two slides 

For about 5 seconds per item, count # of vowels in each word Chair Mathematics Elephant Lamp Car Elevator Thoughtful Cactus Count backward from 100 by 3’s; when you get to 76, write down as many words as you can remember. Do that now. Replication of Craik & Lockhart (1972)

For about 5 seconds per item, visualize how useful the item would be on a deserted island Umbrella Exercise Forgiveness Rock Hamburger Sunlight Coffee Bottle Count backward from 99 by 3’s; when you get to 75, write down as many words as you can remember. Do that now. Replication of Craik & Lockhart (1972); Nairne (2010)

How did you do? Chair Mathematics Elephant Lamp Car Elevator Cactus Thoughtful Umbrella Exercise Forgiveness Rock Hamburger Sunlight Bottle Coffee

What Levels of Processing tells us… Memory for words is better when they are linked to other knowledge Depth of Processing seems to matter Shallow Processing Little attention to meaning Deep Processing Close attention to meaning

Experimental Evidence for LOP Craik & Tulving (1975)

Types of questions Procedure Shallow: Deeper: Deepest: Is the word printed in capital letters? Deeper: Does the word rhyme with train? Deepest: Does the word fit into the sentence “He saw a ____ on the street?” Craik & Tulving (1975)

Levels of Processing Shallow Deeper Deepest Craik & Tulving (1975) Shallow Deeper Deepest Deep processing takes longer but results in better memory.

Aiding Encoding: Forming additional connections Complex or descriptive sentences aid memory Chicken She cooked the chicken. The great bird swooped down and carried off the struggling chicken. Which sentence would help you to remember the word “chicken?”

Forming Visual Images Group 1: Silently repeat Group 2: Mental image Bower & Winzenz (1970) Procedure Paired associate learning paradigm 15 noun pairs; 5 seconds to remember Group 1: Silently repeat Group 2: Mental image After delay, participants are given first word and asked to remember the second Results Group 2 did better; recalled twice as many words See next slide 

Forming Visual Images Results  Interpretation Illustrates the advantage of visual coding Results  Bower & Winzenz (1970)

Linking Words to Yourself Rogers et al. (1977) Experiment 1 Procedure Participants read a question for three seconds and then saw a word They answered yes if the word was in the question and no if it wasn’t Four types of questions: Physical characteristics of word Rhyming Meaning Self-reference

Linking Words to Yourself Exp. 1: Results  Rogers et al. (1977)

Linking Words to Yourself Experiment 2 Results  Rogers et al. (1977)

Why are we more likely to remember words they connect to ourselves? Rogers et al. (1977) Experiments 1 & 2 Interpretation One possible explanation is that the words become linked to something the participants in these experiments know well—themselves

The Generation Effect Slameka & Graf (1978) Procedure Paired associate learning paradigm Participants studied related word pairs Group 1: Read group Group 2: Generate group After delay, participants asked to recall entire word pair Results Group 2 did significantly better Interpretation Generating material yourself, rather than passively receiving it, enhances learning and retention

How do we recall or retrieve information that is not presently in conscious awareness? Retrieval Cues Stimuli that help us to get information stored in LTM Seems to help the best if it taps into information that was encoded at the time of learning

Retrieval Practice Testing Effect Roediger & Karpicke (2009) Procedure Participants read prose passages for 7 minutes followed by a 2-minute break during which they solved math problems. Group 1: Testing group Group 2: Rereading group After various delays, all participants were given recall test

Retrieval Practice Testing Effect Results  Interpretation Retrieval can get better with practice Roediger & Karpicke (2009)

Cued Recall High school students listened to lists of 12, 24, and 48 words Procedure & Results of Tulving & Pearlstone (1966)

Matching Conditions of Encoding & Retrieval Encoding Specificity Principle Godden & Baddeley (1975) Procedure Participants randomly assigned to 4 groups: Listen/Recall Group 1: water/land Group 2: land/water Group 3: water/water Group 4: land/land

Matching Conditions of Encoding & Retrieval Procedure & Results of Gooden & Baddeley (1975)

Matching Conditions of Encoding & Retrieval Procedure & Results of Grant et al. (1998)

Matching Conditions of Encoding & Retrieval Interpretation of both studies: The effect of context is significant Recall is better if the retrieval context is similar to the encoding context Gooden & Baddeley (1975); Grant et al. (1998)

State Dependent Memory Moods Cue Memory is better when a person’s internal state during retrieval matches their internal state during encoding Information learned in a particular emotional state (e.g., depressed, happy, somber) may be more easily recalled when in that same state of mind

State Dependent Memory Procedure & Results of Eich & Metcalfe (1989)

State Dependent Memory Interpretation The effect of context is significant Recall is better if the retrieval context is similar to the encoding context

Transfer Appropriate Processing This phenomenon shows that memory performance is enhanced if the type of task at encoding matches the type of task at retrieval Morris et al. (1977) Procedure The encoding part of the experiment had two conditions: The meaning condition The rhyming condition Participants in both conditions heard a sentence with one word replaced by the word “blank”; 2 seconds later, they heard a target word

Transfer Appropriate Processing Procedure Memory Group Answer “yes” or “no” based on the meaning of the sentence created by replacing “blank” with the target word Rhyme Group Answer “yes” or “no” based on the rhyme created by replacing “blank” with the target word Morris et al. (1977)

Transfer Appropriate Processing Results  Interpretation This result would not be predicted by levels of- processing theory, but is predicted by the principle that better retrieval occurs if the encoding and retrieval tasks are matched Morris et al. (1977)

The Process of Consolidation… Transforming new memories from fragile state (easily lost) to a permanent state (not easily lost) Standard Model of Consolidation Multiple Trace Hypothesis

Standard Model of Consolidation This model posits that the hippocampus important at first; not so much later Reactivation A process in which the hippocampus replays the neural activity associated with memory This activity results in the formation of connections between the cortical areas This reactivation process occurs during sleep or during periods of relaxed wakefulness, and can also be enhanced by conscious rehearsing of a memory

Standard Model of Consolidation Reactivation Eventually, the cortical connections become strong enough so that the different sites in the cortex become directly linked, and the hippocampus is no longer necessary Thus, according to the standard model of consolidation, the hippocampus is strongly active when memories are first formed but become less active as memories are consolidated, until eventually only cortical activity is necessary to retrieve remote memories

Standard Model of Consolidation Evidence for this model comes from occurrences of graded amnesia Retrograde amnesia is most severe for events that occurred just before an injury Retrograde amnesia Loss of memory for events that have happened prior to trauma or disease

Standard Model of Consolidation Gradual decrease in amnesia for past events supports idea that connections between hippocampus the cortical are formed and strengthened as time passes after an event and then vanish Hippocampus is strongly active when memories are initially formed and recalled Then becomes less involved as memories are consolidated Eventually, the connections between the cortical areas themselves are enough to access remote memories

The Process of Consolidation… Multiple Trace Hypothesis (MTH) Hippocampus’ influence is important during latter stages of memory formation as well Gilboa et al. (2004) Participants shown photographs of themselves engaging in various activities at times ranging from very recently to when they were 5 years old The results of this experiment showed that the hippocampus was activated during retrieval of both recent and remote memories

Reconsolidation This theory posits that when a memory is retrieved, it returns to the STM state If undisturbed it will undergo consolidation again back into LTM However, it may not go undisturbed and is susceptible to alteration at this time Since reactivated memory is in a labile state, it can be blocked (just as in consolidation)

Credits Some of the slides in this presentation prepared with the assistance of the following web sites: www.radford.edu/dhall/Matlin%20powerpoints/ch05%20edited .ppt archlab.gmu.edu/people/jthompsz/6-LongTermMemory_2.ppt