PDF created with pdffactory trial version Control of memory

Transcription

1 Control of memory

2 Craik, Govoni, Naveh-Benjamin, & Anderson (1996): Retrieval mode Words were presented auditorily and recalled verbally. The secondary visual-manual task required pressing a key where an asterisk appeared, causing the asterisk to immediately jump to another position. Free recall (above) and cued recall (below) results show that dividing attention at encoding impairs memory while dividing attention at recall does not. The effect on reaction time to the asterisk is explained in terms of retrieval mode

3 Memory retrieval monitoring Meta-memory: One s knowledge about and control over memory processes Feeling of knowing: How do we know that we know something How do we know that we remember something? How do we control our memory output?

4 Koriat, 1993, Feeling of knowing: People do not have privileged access to their own memory, and therefore rely on cues (the amount of partial information they can recall, regardless of its correctness) to estimate how much they know. Participants study letter strings such as CFXA and are asked to recall as many of the letters as they can. Two scores are generated: number of correct letters (PI-C) and number of wrong letters (PI-W).

5 Regulation of Memory Grain Size Goldsmith, Koriat, Weinberg-Eliezer, 2002 When did André Agassi win Wimbledon? Fine Grained Answer Specifies the year of the victory Coarse Grained Answer Identifies the decade Goal of Strategic Regulation: To regulate the grain size of memory

6 Strategic Regulation PERSONAL GOALS & TASK DEMANDS Encoding Representation Retrieval Monitoring Control Output Best Candidate Response Accuracy Informativeness Response Criteria Memory Metamemory Performance

7 When did André Agassi win Wimbledon? In the 90s 80% sure Penalty for low informativeness CRITERION 1992 Reward for accuracy Between % sure

8 Regulating Grain Size (the goal of metamemory) Monitoring Mechanisms Calibration Assessed probability that a memory is correct Resolution Whether the memory is correct enough Control Processes Setting Criterion Synchronizing output to task demands

9 Monitoring Mechanisms 2: Resolution Whether I choose memories that are optimally informative yet maintain a criterion level of accuracy e.g. 40% accuracy acceptable Question 1 Question 2 Question 3 Fine Grain 20% 50% 10% Coarse Grain 80% 90% 40%

10 Phase 1: Phase 2: Go over your answers from before, and then choose the grain.

11 Remembering is not always helpful Automaticity: The task is performed even when it is not required, and sometimes in spite of instructions not to perform it (Stroop) Recall: the wrong answer may pop to mind, and get in the way of the right answer. Trauma: The memory of the trauma may pop uncontrollably into consciousness

12 Control over automaticity (Tzelgov, Henik & Leiser, 1990). Stoop interference: Color naming RT in incongruent (RED) minus congruent (GREEN) Stroop interference (ms) Secondary frequent Secondary infrequent Dominant infrequent Dominant frequent Arab bilinguals Jewish billinguals Arab and Jewish billinguals were tested with a mixture of Arabic and Hebrew words, when the proportion of words of each language was changed Language mastery determines one s ability to reduce Stroop interference

13 Inhibitory control in selective memory retrieval When we retrieve a memory, there are many traces related to it Retrieval would be faster if interfering traces were suppressed Therefore, if inhibitory mechanisms suppress competing traces, those traces should be harder to remember later

14 Retrieval Practice Paradigm 1. Study category-exemplar sets 2. Retrieval practice--cued stem-recall ex. Fruit-orange 3. Final cued recall test 20 minutes later

15 Retrieval-induced forgetting Practiced exemplars were better recalled Impairment on unpracticed competitors (compared to baseline exemplars) shows RIF

16 Inhibition? Retrieval practice can lead to: 1. Strengthening of cue-target associations 2. Weakening of unpracticed associations 3. Biasing meaning of category cue (making it a useless cue for retrieving unpracticed competitors) If it s inhibition, impairment should generalize to other related cues

17 Modified Paradigm Like original study - but this time used words that fell under more than one category and then tested words using novel cues

18 Think/No-Think Paradigm Purpose: to use response-override mechanisms as an analogy for the inhibitory control of retrieval 1. Subjects study weakly-related words -ex. flag-sword, ordeal-roach, (cue-response) 2. Provide response to cue quickly 3. Think/No-Think phase -some responses forcibly suppressed 4. Recall all responses

19

20 Original Monetary reward for successful retrieval Predicted paradoxical facilitation Think but do not respond

21 Anderson et al., 2005 fmri BOLD responses during the think no-think phase: No-think minus think. Hippocampal deactivation is observed in the no-think condition relative to the think condition

22

23 Control of memory Craik, Govoni, Naveh-Benjamin, & Anderson (1996): Retrieval mode Words were presented auditorily and recalled verbally. The secondary visual-manual task required pressing a key where an asterisk appeared, causing the asterisk to immediately jump to another position. Free recall (above) and cued recall (below) results show that dividing attention at encoding impairs memory while dividing attention at recall does not. The effect on reaction time to the asterisk is explained in terms of retrieval mode Memory retrieval monitoring Meta-memory: One s knowledge about and control over memory processes Feeling of knowing: How do we know that we know something How do we know that we remember something? How do we control our memory output? 1

24 Koriat, 1993, Feeling of knowing: People do not have privileged access to their own memory, and therefore rely on cues (the amount of partial information they can recall, regardless of its correctness) to estimate how much they know. Participants study letter strings such as CFXA and are asked to recall as many of the letters as they can. Two scores are generated: number of correct letters (PI-C) and number of wrong letters (PI-W). Regulation of Memory Grain Size Goldsmith, Koriat, Weinberg-Eliezer, 2002 When did André Agassi win Wimbledon? Fine Grained Answer Specifies the year of the victory Coarse Grained Answer Identifies the decade Goal of Strategic Regulation: To regulate the grain size of memory Strategic Regulation PERSONAL GOALS & TASK DEMANDS Encoding Representation Retrieval Monitoring Control Output Best Candidate Response Accuracy Informativeness Response Criteria Memory Metamemory Performance 2

25 When did André Agassi win Wimbledon? In the 90s 80% sure 1992 Penalty for low informativeness CRITERION Reward for accuracy Between % sure Regulating Grain Size (the goal of metamemory) Monitoring Mechanisms Calibration Assessed probability that a memory is correct Resolution Whether the memory is correct enough Control Processes Setting Criterion Synchronizing output to task demands Monitoring Mechanisms 2: Resolution Whether I choose memories that are optimally informative yet maintain a criterion level of accuracy e.g. 40% accuracy acceptable Question 1 Question 2 Question 3 Fine Grain 20% 50% 10% Coarse Grain 80% 90% 40% 3

26 Phase 1: Phase 2: Go over your answers from before, and then choose the grain. Remembering is not always helpful Automaticity: The task is performed even when it is not required, and sometimes in spite of instructions not to perform it (Stroop) Recall: the wrong answer may pop to mind, and get in the way of the right answer. Trauma: The memory of the trauma may pop uncontrollably into consciousness Control over automaticity (Tzelgov, Henik& Leiser, 1990). Stoop interference: Color naming RT in incongruent (RED) minus congruent (GREEN) Stroop interference (ms) Secondary frequent Secondary infrequent Dominant infrequent Dominant frequent Arab bilinguals Jewish billinguals Arab and Jewish billinguals were tested with a mixture of Arabic and Hebrew words, when the proportion of words of each language was changed Language mastery determines one s ability to reduce Stroop interference 4

27 Inhibitory control in selective memory retrieval When we retrieve a memory, there are many traces related to it Retrieval would be faster if interfering traces were suppressed Therefore, if inhibitory mechanisms suppress competing traces, those traces should be harder to remember later Retrieval Practice Paradigm 1. Study category-exemplar sets 2. Retrieval practice--cued stem-recall ex. Fruit-orange 3. Final cued recall test 20 minutes later Retrieval-induced forgetting Practiced exemplars were better recalled Impairment on unpracticed competitors (compared to baseline exemplars) shows RIF 5

28 Inhibition? Retrieval practice can lead to: 1. Strengthening of cue-target associations 2. Weakening of unpracticed associations 3. Biasing meaning of category cue (making it a useless cue for retrieving unpracticed competitors) If it s inhibition, impairment should generalize to other related cues Modified Paradigm Like original study - but this time used words that fell under more than one category and then tested words using novel cues Think/No-Think Paradigm Purpose: to use response-override mechanisms as an analogy for the inhibitory control of retrieval 1. Subjects study weakly-related words -ex. flag-sword, ordeal-roach, (cue-response) 2. Provide response to cue quickly 3. Think/No-Think phase -some responses forcibly suppressed 4. Recall all responses 6

29 Original Monetary reward for successful retrieval Predicted paradoxical facilitation Think but do not respond Anderson et al., 2005 fmri BOLD responses during the think no-think phase: No-think minus think. Hippocampal deactivation is observed in the no-think condition relative to the think condition 7

30 8