Human Cognitive Processes: psyc 345 Ch. 7 Long-term memory: Encoding and retrieval Takashi Yamauchi © Takashi Yamauchi (Dept. of Psychology, Texas A&M University)

(Q1) What is the best way to store information in long-term memory? (Q2) What are some techniques to help us get information out of LTM when we need it? (Q3) How is it possible that a lifetime of experiences and accumulated knowledge can be stored in neurons?

(Q1) What is the best way to store information in long-term memory?

Encoding What encoding strategy enhances long term memory? 1k&NR=1http:// 1k&NR=1

Level-of-processing theory Memory depends on depth of processing Deep processing vs. shallow processing –Focusing on an item’s meaning and relating it to something else. Shallow processing –Little attention to meaning, attention to physical features to items. Rote memory

Craik & Tulving (1975) Experiments: –Levels of processing and remembering –Deep processing helps (Processing semantic information helps) CogLab: level of processing

Experiment: Tasks: –Subjects were shown words one by one on a screen. –They carried out one of 3 different tasks.

Task1: Capital letters? low semantic involvement –Ss judged whether the word presented on the screen is printed with capital letters or not. –TRAIN  yes –Table  no

Task2: Rhyme? –In another trial, Ss were shown a word (e.g., TRAIIN) and judged whether or not the word rhymed with a word (e.g., BRAIN). Train  brain -  yes Crate  weight  yes Table  cable  yes Book –> note  no

Task 3: Fill in the blanks –Ss judged whether or not the word shown first fitted a particular sentence. –E.g., “friend” was shown, and a sentence “He met a in the street” was shown. The answer is “yes”.

Different levels of depth Task 1 < Task 2 < Task 3

Memory test (recognition): After Ss carried out these tasks, then a list of 80 words was given. –In the list, 40 words appeared during the first phase. –40 words were new words that did not appear in the first phase. Ss indicated the words that they remember from the first phrase.

These tasks differ in the level of processing.

Processing semantic information The three tasks differed in the degree to which semantic information was processed. Fill in blanks > Rhyme > Capital letter

Level of processing: (2:22) – 1k&NR=1http:// 1k&NR=1

Fig. 6-18, p. 206 Additional factors that aid encoding

Creating connections –Visualizing study items. –Relating study items to yourself. –Generating study items by yourself

Bower & Winzenz (1970) –Ss received a list of 15 pairs, (boat, tree)… –One group were told to just repeat the words. –Another group were told to form mental pictures

Ss in the mental picture group were able to recall twice as many words as the Ss in the repeat group.

Self-referencing effect Ss received a word list. –Sad, positive, overwhelming, sly, shy, happy,… –They answered yes-no questions

happy –Printed in small case? (physical characteristics) snappy –Rhymes with happy? (rhyming) upbeat –Means the same as happy? (meaning) happy –Describe you? (self-reference)

(Q2) What are some techniques to help us get information out of LTM when we need it?

Retrieving information from LTM What are effective ways of encoding and retrieving? Using retrieval cues Retrieval cues are like “hints” that are useful for retrieving memories.

Cued recall Mantyla (1986) Ss received a list of 600 nouns –(e.g., banana, freedom, tree, …) During learning, Ss wrote down three words and associated the words with each noun. –E.g., banana  yellow, bunches and edible.

Cued recall Ss were given a surprise memory test. Ss were presented with the three words they had created. –e.g., yellow, bunches and edible 90% of the 600 words were recalled correctly.

Another group of participants: –Did not create their own cues –But they were given cues that were produced by someone else E.g., banana  yellow, bunches and edible. 55% of the words were recalled.

Fig. 6-28, p. 217

Creating your own retrieval cues during encoding REALLY helps

Encoding specificity How are encoding and retrieval related? Encoding specificity theory –Memory retrieval is effective to the extent by which the context of encoding corresponds to the context of retrieval (Tulving & Thompson, 1973)

Godden & Baddeley (1975) –One group of Ss studied a list of words underwater. –Another group studied the words on land. –At test, each group was further divided into and recalled the words either underwater or on land.

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.

Grant et al. (1998) 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.

Other methods to improve your memory (2:50) &feature=relatedhttp:// &feature=related Things that impede your memory (1:35) U&feature=PlayList&p=8DE5E0C927437E3B&pl aynext=1&playnext_from=PL&index=32http:// U&feature=PlayList&p=8DE5E0C927437E3B&pl aynext=1&playnext_from=PL&index=32

(Q3) How is it possible that a lifetime of experiences and accumulated knowledge can be stored in neurons?

How are memories stored in the brain Hebb (1948) Learning and memory are represented by physiological changes at the synapse. Long-term potentiation (LTP)

Neuron IV

Neurons Dendrites Cell body Axon

Synapse

DendriteAxon Synapse Synapse and neurotransmitter neurotransmitters reach a terminal of a dendrite of the other neuron, and change the neuron’s resting potential.

Fig. 6-20, p. 209

Neuroanimator demonstration –Ch 13. 3: Long-lasting LTP

Forming Memories in the brain: The fragility of new memories Memory loss Teenage memory loss due to concussion (2:11) – hQ H. M. –his hippocampus is surgically removed. –He cannot form new memories –He also lost memories of events up to years before the operation.

Fig. 6-21, p. 209 H. M. had both anterograde and retrograde amnesia

Consolidation These examples show that memory for recent events is more fragile. Some process of transferring of memory occurs.  Consolidation –Transforms new memories to a stronger less fragile state.

Consolidation Retrieval of episodic memory initially depends on the hippocampus. Later, the hippocampus is not involved in retrieval. How does it happen? -- >reactivation

Fig. 6-22, p. 211 Incoming information activates cortical areas and the hippocampus The hippocampus replays the neural activities associated with a memory. This results in the formation of connections between cortical areas. Eventually, the cortical connections become strong enough, and the hippocampus is no longer necessary.

What creates consolidation? Sleeping helps strengthen memory. A lot of neural connections between hippocampus and neocortex. Neurons in hippocampus send neural signals to neurons in neocortex while you sleep.

Synapse and learning (10:45) Teenagers and sleep deprivation – o&feature=PlayList&p=8DE5E0C927437E3B &index=24&playnext=2&playnext_from=PLhttp:// o&feature=PlayList&p=8DE5E0C927437E3B &index=24&playnext=2&playnext_from=PL Poor sleep and Alzheimer’s disease – _dk

Additional materials

Memory for emotion A strong connection between emotion and memory. We tend to remember well emotionally charged experiences (both negative and positive). Why?

Fig. 6-26, p. 214 LaBar & Phelps (1998) Arousing words (profanity, sexually explicit words) are remembered better than neutral words Dolcos et al. (2005) Emotional pictures are also remembered better than neutral pictures.

Why The amygdala is the center for processing emotion. The hippocampus is right next to the amygdala.

What happens if you don’t have amygdala? DVD: Secrets of the mind –(Capgras delusion; from 29:00 to 39:00 ) 10 min. A case study (imposter feeling) of a patient with the damage to amygdala.