Forgetting and Memory Errors
Introduced| English | Meaning |
|---|---|
| forgetting curve/fəˈɡetɪŋ kɜːv/ | A graph showing how retained information changes with time after learning, often declining most rapidly at first. |
| Encoding failure/enˈkəʊdɪŋ ˈfeɪlɪə/ | Never storing the information, so it cannot later be found. |
| Interference/ˌɪntəˈfɪərəns/ | Disruption of learning or remembering caused by competing information or memories. |
| proactive/prəʊˈæktɪv/ | Describing interference in which previously learned information makes newer information harder to remember. |
| retroactive/ˌretrəʊˈæktɪv/ | Describing interference in which newer learning makes previously learned information harder to remember. |
| Retrieval failure/rɪˈtriːvl ˈfeɪlɪə/ | Having stored information but being unable to get it out. |
| repression/rɪˈpreʃn/ | In psychodynamic theory, keeping distressing thoughts or memories outside conscious awareness. |
| misinformation effect/ˌmɪsɪnfəˈmeɪʃn ɪˈfekt/ | A change in memory reports caused by misleading information received after an event. |
| Source amnesia/sɔːs æmˈniːzɪə/ | Remembering information while failing to remember where, when or from whom it was obtained. |
| Constructive memory/kənˈstrʌktɪv ˈmeməri/ | Constructive memory |
Most of what you forget goes in the first hours
- Forgetting is not a slow, even leak.
- The forgetting curve 遗忘曲线 falls steeply just after learning, then levels off.
- That shape is why when you review matters as much as how long.
The forgetting curve shows a steady, even loss across the whole period.
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It falls steeply just after learning, then levels off — which is why early review matters.
Three reasons a memory will not come
- Encoding failure 编码失败 — it never went in properly.
- Interference 干扰 — proactive 前摄干扰 (old blocks new) or retroactive 倒摄干扰 (new blocks old).
- Retrieval failure 提取失败 — it is stored, but the cue is missing.
Four different failures, all reported as forgetting- the tell is what a cue does
Proactive: old blocks new. Retroactive: new blocks old.
Why did this memory fail?
Sort each case by the reason the CED would give.
Proactive interference means...
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Proactive = the prior learning is doing the blocking.
Motivated forgetting
- Psychodynamic theorists propose repression 压抑 — forgetting that defends the ego from distress.
- The CED presents this as a theory, not an established mechanism.
- Naming it as a psychodynamic claim, rather than a fact, is what a careful answer does.
Match each failure to where it happens.
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The three failures sit at three different points in the memory process.
Do not treat proactive and retroactive interference as interchangeable. Proactive means old learning blocks new; retroactive means new blocks old. Getting the direction backwards is one of the most common lost marks in this unit.
Information met after an event changing the memory of it is the ____ effect.
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The misinformation effect is why question wording can change eyewitness testimony.
Select all the memory errors the CED names.
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Chunking is an encoding strategy, not a memory error.
Memory is reconstructed, not replayed
- The misinformation effect 错误信息效应 means information met after an event changes the memory of it.
- Source amnesia 来源遗忘 is remembering the content but not where it came from.
- Constructive memory 建构性记忆 means you rebuild a memory each time, filling gaps with what is plausible.
Why this matters outside the exam
- A confident memory and an accurate memory are not the same thing.
- Eyewitness testimony can be changed by the wording of a question asked afterwards.
- The CED expects you to treat vividness as no evidence of accuracy.
Witnesses shown the same crash film gave higher speed estimates when asked how fast the cars "smashed" rather than "hit". The film did not change — the misinformation effect changed the memory of it.
The forgetting curve falls steeply then levels. Memories fail through encoding failure, interference (proactive = old blocks new, retroactive = new blocks old) or retrieval failure. Repression is a psychodynamic theory. The misinformation effect, source amnesia and constructive memory show memory is rebuilt, not replayed.
Write from 12 items lost on the first day
- A student recalls 20 items at once, 8 a day later, and 6 after another 6 days.
- Describe the shape of the loss. Say what proactive interference is.
Recall falls from 20 items to 8 after one day, then to 6 after six more days. What does that shape show, and what is proactive interference?
20 minus 8 is 12, and 8 minus 6 is 2. The early drop is the steep part of the curve.
How many items are lost on the first day?
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20 minus 8 is 12. The later change from 8 to 6 is much smaller.