8 Memory · 8.1 Memory
8.1.2 Measuring memory, forgetting and mnemonics
Memory is measured directly (recall, recognition) or indirectly (relearning savings, priming), and by how faithfully a person reconstructs material; we forget because traces decay, are displaced or interfered with, cannot be retrieved without the right cue, or are pushed away for emotional reasons; and mnemonics fight forgetting with images (loci, keyword, peg-word) and organisation (chunking, first letters). The memory stores and types are in PSY-MM-01; study methods, overlearning and SQ3R are in EDU-LR-01.
- APPSC Paper I
- Standard level
- 13 min read
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Core facts
- Two kinds of measure:
- Direct (explicit): the person is asked to remember on purpose: recall and recognition.
- Indirect (implicit): memory shows up in performance without being asked for: relearning (savings) and priming.
- Recall: reproducing learnt material without the material in front of you (fill in the blank, essay). Forms:
- Free recall: in any order;
- Serial recall: in the original order;
- Cued recall / paired associates: a cue (first word of a pair) is given and the partner must be recalled.
- Recognition: identifying learnt items among new ones (MCQ, picking a face in a line-up). Easier and more sensitive than recall.
- Relearning / savings method: Hermann Ebbinghaus (1885); learn the material again and measure the time or trials saved.
- Savings score = (original trials − relearning trials) ÷ original trials × 100.
- It shows memory even when nothing can be recalled or recognised; the most sensitive measure.
- Reconstruction: the person puts items back in their original order or arrangement; in a wider sense, remembering is an active rebuilding of the past (F.C. Bartlett, 1932, the "War of the Ghosts" story; schemas fill gaps).
- Ebbinghaus's forgetting curve: loss is fastest soon after learning, then slows and levels off. He used nonsense syllables on himself.
- Theories of forgetting:
- Trace decay: traces fade with time and disuse (Thorndike's law of disuse).
- Displacement: STM has limited slots; new items push old ones out.
- Interference: other learning gets in the way:
- Proactive: earlier learning disrupts recall of later learning;
- Retroactive: later learning disrupts recall of earlier learning.
- Retrieval (cue-dependent) failure: the memory is stored but the right cue is missing (Tulving); "tip of the tongue" state.
- Motivated forgetting / repression: Freud; painful memories are kept out of awareness.
- Also: consolidation failure (injury before a trace is fixed) and organic causes (amnesia, Alzheimer's).
- STM forgetting: explained mainly by trace decay and displacement. LTM forgetting: mainly by interference and retrieval failure.
- Jenkins and Dallenbach (1924): subjects who slept after learning forgot less than those who stayed awake: support for interference over pure decay.
- Mnemonics: memory aids that give unfamiliar or abstract material a structure or an image. Two groups (NCERT names keyword and loci under images; the peg-word method is from other textbooks):
- Using images: keyword method, method of loci, peg-word method.
- Using organisation: chunking, first-letter technique (acronyms like VIBGYOR / ROYGBIV, HOMES for the Great Lakes; acrostic sentences).
- Method of loci: picture a familiar place (rooms of your house, a familiar route) and "place" each item at a spot; walk through it to recall. Credited to the ancient Greek poet Simonides.
- Keyword method: for a new foreign word, find an English word that sounds like it and form an image linking the two (for learning vocabulary).
- Peg-word method: learn rhyming "pegs" (one is a bun, two is a shoe, three is a tree...) and hang each item on its peg with an image.
Explained
1. Measures compared
| Method | What the person does | Type | Strength |
|---|---|---|---|
| Recall | produces the item with few or no cues | direct | hardest; shows the least retained |
| Recognition | picks the item from alternatives | direct | easier; shows more retained |
| Relearning (savings) | learns again; trials saved are counted | indirect | most sensitive |
| Reconstruction | rebuilds order or content | direct | shows distortion by schemas |
A student may fail to recall a definition (recall), still pick it in an MCQ (recognition), and relearn it in half the time a month later (savings). All three show some memory.
2. A savings example. A list took 20 trials to learn. A week later it took 8 trials to relearn. Savings = (20 − 8) ÷ 20 × 100 = 60%.
3. Recognition and its errors. In recognition tests a person can say "yes" to a new item (false alarm) or "no" to an old one (miss). Eyewitness line-ups are recognition tasks, which is why false identifications happen.
4. Reconstruction and eyewitness memory. Bartlett's British students retold a Native American folk tale ("The War of the Ghosts"); with each retelling it became shorter, more familiar and fitted their culture. Elizabeth Loftus and Palmer (1974): people who heard the word "smashed" instead of "hit" estimated higher car speeds and later "remembered" broken glass that was not there (misinformation effect). For a probation officer, this matters: a child's or witness's account can change with leading questions.
5. Theories of forgetting compared
| Theory | Cause | Best explains | Key name |
|---|---|---|---|
| Trace decay | fading with time and disuse | STM loss, old unused facts | Thorndike (disuse) |
| Displacement | new items push out old in STM | losing a number when interrupted | Waugh and Norman |
| Interference | other learning competes | similar material learnt close together | Jenkins and Dallenbach |
| Retrieval failure | cue missing | tip of the tongue | Tulving |
| Motivated forgetting | emotional defence | traumatic events | Freud |
6. Proactive vs retroactive interference: the test. Ask which memory is being lost. If the material learnt before spoils it, it is proactive (acts forward). If the material learnt after spoils it, it is retroactive (acts backward).
- You keep writing last year's date in January: old habit blocks new → proactive.
- After learning a new phone number you cannot remember the old one → retroactive.
Interference is greatest when the two sets of material are similar.
7. Cue-dependent forgetting and its forms
- Encoding specificity (Tulving): recall is best when the cues at retrieval match those at encoding.
- Context-dependent memory: divers who learnt words underwater recalled them better underwater (Godden and Baddeley, 1975).
- State-dependent memory: recall is better in the same bodily or emotional state as at learning.
- Tip-of-the-tongue (TOT) state (Brown and McNeill, 1966): you know the first letter or number of syllables but not the word.
8. Mnemonics: the two groups (images and organisation)
| Group | Method | How it works | Example |
|---|---|---|---|
| Images | Method of loci | items placed along a familiar place or route | shopping list placed in rooms of your house |
| Images | Keyword | sound-alike English word + linking image | learning a Telugu or French word |
| Images | Peg-word | rhyme pegs + image | "one is a bun": a bun holding the first item |
| Organisation | Chunking | group items into meaningful units | 9849 123 456 as three chunks |
| Organisation | First-letter | initials form a word or sentence | VIBGYOR, HOMES |
Mnemonics help most with unfamiliar, abstract or list-type material. Understanding the material, deep (semantic) processing, distributed practice, overlearning and self-testing remain the main ways to improve memory (see EDU-LR-01).
9. Confusable pairs
| Pair | First one | Second one |
|---|---|---|
| Recall vs recognition | produce without options (harder) | choose among options (easier) |
| Relearning vs reconstruction | trials saved on learning again | rebuilding order or content |
| Direct vs indirect measure | recall, recognition (explicit) | savings, priming (implicit) |
| Decay vs displacement | fading over time | pushed out by new items |
| Decay vs interference | time alone | other learning competes |
| Proactive vs retroactive | old blocks new | new blocks old |
| Retrieval failure vs repression | cue missing | emotional defence (Freud) |
| Method of loci vs peg-word | familiar places | rhyming number pegs |
| Keyword vs peg-word | sound-alike word for vocabulary | fixed list of rhyme pegs |
| Chunking vs first-letter | group items into units | initials into a word |
| Imagery vs organisation mnemonics | loci, keyword, peg-word | chunking, first-letter |
Common traps
- ✗ "Recognition is harder than recall." ✓ Recall is harder; recognition is easier.
- ✗ "The savings method is a direct method." ✓ Savings (relearning) is an indirect measure; recall and recognition are direct.
- ✗ "Bartlett invented the savings method." ✓ Savings = Ebbinghaus (1885); reconstruction and schemas = Bartlett (1932).
- ✗ "Proactive interference: new learning blocks old." ✓ That is retroactive; proactive = old blocks new.
- ✗ "STM forgetting is best explained by repression." ✓ STM forgetting = trace decay and displacement.
- ✗ "Jenkins and Dallenbach supported decay." ✓ Their sleep study supported interference.
- ✗ "Tip-of-the-tongue shows the memory is lost." ✓ It shows retrieval failure: the memory is stored.
- ✗ "Method of loci uses rhymes." ✓ Loci uses familiar places; the peg-word method uses rhymes.
- ✗ "Chunking is an imagery mnemonic." ✓ Chunking and first-letter are organisation mnemonics; loci, keyword and peg-word use images.
- ✗ "Forgetting is fastest weeks after learning." ✓ It is fastest soon after learning, then levels off (Ebbinghaus).
Quick revision
- Direct measures: recall, recognition; indirect: relearning (savings), priming.
- Recall forms: free, serial, cued / paired associates; recognition is easier than recall.
- Savings = (original − relearning trials) ÷ original × 100; Ebbinghaus 1885, most sensitive.
- Reconstruction: Bartlett 1932, "War of the Ghosts", schemas; Loftus: misinformation.
- Forgetting curve: steep early fall, then levels off.
- STM forgetting: decay and displacement; LTM forgetting: interference and retrieval failure.
- Proactive = old blocks new; retroactive = new blocks old; Jenkins and Dallenbach 1924: sleep reduces interference.
- Retrieval failure: cue-dependent (Tulving), tip of the tongue; repression: Freud.
- Image mnemonics: loci (familiar places), keyword (sound-alike), peg-word (one is a bun).
- Organisation mnemonics: chunking, first-letter (VIBGYOR, HOMES).
Go deeper: Deeper (beyond what APPSC Paper I usually asks)
Deeper Advanced
1. Is decay real? Decay is hard to test, because time always brings new events that could interfere. Jenkins and Dallenbach's sleep study suggests much "decay" is really interference. Decay is still accepted as a factor in sensory memory and STM.
2. Release from proactive interference (Wickens, 1972). When people recall several lists of the same category (fruits, fruits, fruits), recall falls with each list. When the category changes (to professions), recall jumps back up. This shows proactive interference builds with similar material.
3. Repression and recovered memories. Freud's idea is hard to test, and research on "recovered memories" of childhood abuse is contested: some may be real, some may be created by suggestive questioning (Loftus). Probation and child-protection work avoids leading questions for this reason.
4. Why recognition beats recall. Recall needs two steps (search for the item, then decide it is right); recognition needs only the second. This is the "generate-recognise" view.
5. Signal detection in recognition. A good recognition score is not just "hits"; it is hits relative to false alarms. A person who says "yes" to everything has many hits and many false alarms, so the true memory is low.
Practise this topic. Questions on Measuring memory, forgetting and mnemonics, with answers explained.
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